/export/starexec/sandbox2/solver/bin/starexec_run_standard /export/starexec/sandbox2/benchmark/theBenchmark.jar /export/starexec/sandbox2/output/output_files
--------------------------------------------------------------------------------
YES
proof of /export/starexec/sandbox2/benchmark/theBenchmark.jar
# AProVE Commit ID: 48fb2092695e11cc9f56e44b17a92a5f88ffb256 marcel 20180622 unpublished dirty
termination of the given Bare JBC problem could be proven:
(0) Bare JBC problem
(1) BareJBCToJBCProof [EQUIVALENT, 96 ms]
(2) JBC problem
(3) JBCToGraph [EQUIVALENT, 1506 ms]
(4) JBCTerminationGraph
(5) TerminationGraphToSCCProof [SOUND, 1 ms]
(6) JBCTerminationSCC
(7) SCCToIRSProof [SOUND, 389 ms]
(8) IRSwT
(9) IRSFormatTransformerProof [EQUIVALENT, 0 ms]
(10) IRSwT
(11) IRSwTTerminationDigraphProof [EQUIVALENT, 106 ms]
(12) IRSwT
(13) IntTRSCompressionProof [EQUIVALENT, 0 ms]
(14) IRSwT
(15) TempFilterProof [SOUND, 126 ms]
(16) IntTRS
(17) PolynomialOrderProcessor [EQUIVALENT, 15 ms]
(18) IntTRS
(19) PolynomialOrderProcessor [EQUIVALENT, 0 ms]
(20) YES
----------------------------------------
(0)
Obligation:
need to prove termination of the following program:
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the Collection
* interface, to minimize the effort required to implement this interface.
*
* To implement an unmodifiable collection, the programmer needs only to
* extend this class and provide implementations for the iterator and
* size methods. (The iterator returned by the iterator
* method must implement hasNext and next.)
*
* To implement a modifiable collection, the programmer must additionally
* override this class's add method (which otherwise throws an
* UnsupportedOperationException), and the iterator returned by the
* iterator method must additionally implement its remove
* method.
*
* The programmer should generally provide a void (no argument) and
* Collection constructor, as per the recommendation in the
* Collection interface specification.
*
* The documentation for each non-abstract method in this class describes its
* implementation in detail. Each of these methods may be overridden if
* the collection being implemented admits a more efficient implementation.
*
* This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Collection
* @since 1.2
*/
public abstract class AbstractCollection implements Collection {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractCollection() {
}
// Query Operations
/**
* Returns an iterator over the elements contained in this collection.
*
* @return an iterator over the elements contained in this collection
*/
public abstract Iterator iterator();
public abstract int size();
/**
* {@inheritDoc}
*
* This implementation returns size() == 0.
*/
public boolean isEmpty() {
return size() == 0;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the elements in the collection,
* checking each element in turn for equality with the specified element.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public boolean contains(Object o) {
Iterator e = iterator();
if (o==null) {
while (e.hasNext())
if (e.next()==null)
return true;
} else {
while (e.hasNext())
if (o.equals(e.next()))
return true;
}
return false;
}
// Modification Operations
/**
* {@inheritDoc}
*
* This implementation always throws an
* UnsupportedOperationException.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IllegalStateException {@inheritDoc}
*/
public boolean add(E e) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the collection looking for the
* specified element. If it finds the element, it removes the element
* from the collection using the iterator's remove method.
*
*
Note that this implementation throws an
* UnsupportedOperationException if the iterator returned by this
* collection's iterator method does not implement the remove
* method and this collection contains the specified object.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public boolean remove(Object o) {
Iterator e = iterator();
if (o==null) {
while (e.hasNext()) {
if (e.next()==null) {
e.remove();
return true;
}
}
} else {
while (e.hasNext()) {
if (o.equals(e.next())) {
e.remove();
return true;
}
}
}
return false;
}
// Bulk Operations
/**
* {@inheritDoc}
*
* This implementation iterates over the specified collection,
* checking each element returned by the iterator in turn to see
* if it's contained in this collection. If all elements are so
* contained true is returned, otherwise false.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @see #contains(Object)
*/
public boolean containsAll(Collection c) {
Iterator e = c.iterator();
while (e.hasNext())
if (!contains(e.next()))
return false;
return true;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the specified collection, and adds
* each object returned by the iterator to this collection, in turn.
*
*
Note that this implementation will throw an
* UnsupportedOperationException unless add is
* overridden (assuming the specified collection is non-empty).
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IllegalStateException {@inheritDoc}
*
* @see #add(Object)
*/
public boolean addAll(Collection c) {
boolean modified = false;
Iterator e = c.iterator();
while (e.hasNext()) {
if (add(e.next()))
modified = true;
}
return modified;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over this collection, checking each
* element returned by the iterator in turn to see if it's contained
* in the specified collection. If it's so contained, it's removed from
* this collection with the iterator's remove method.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by the
* iterator method does not implement the remove method
* and this collection contains one or more elements in common with the
* specified collection.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*
* @see #remove(Object)
* @see #contains(Object)
*/
public boolean removeAll(Collection c) {
boolean modified = false;
Iterator e = iterator();
while (e.hasNext()) {
if (c.contains(e.next())) {
e.remove();
modified = true;
}
}
return modified;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over this collection, checking each
* element returned by the iterator in turn to see if it's contained
* in the specified collection. If it's not so contained, it's removed
* from this collection with the iterator's remove method.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by the
* iterator method does not implement the remove method
* and this collection contains one or more elements not present in the
* specified collection.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*
* @see #remove(Object)
* @see #contains(Object)
*/
public boolean retainAll(Collection c) {
boolean modified = false;
Iterator e = iterator();
while (e.hasNext()) {
if (!c.contains(e.next())) {
e.remove();
modified = true;
}
}
return modified;
}
/**
* {@inheritDoc}
*
* This implementation iterates over this collection, removing each
* element using the Iterator.remove operation. Most
* implementations will probably choose to override this method for
* efficiency.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by this
* collection's iterator method does not implement the
* remove method and this collection is non-empty.
*
* @throws UnsupportedOperationException {@inheritDoc}
*/
public void clear() {
Iterator e = iterator();
while (e.hasNext()) {
e.next();
e.remove();
}
}
// String conversion
/**
* Returns a string representation of this collection. The string
* representation consists of a list of the collection's elements in the
* order they are returned by its iterator, enclosed in square brackets
* ("[]"). Adjacent elements are separated by the characters
* ", " (comma and space). Elements are converted to strings as
* by {@link String#valueOf(Object)}.
*
* @return a string representation of this collection
*/
public String toString() {
Iterator i = iterator();
if (! i.hasNext())
return "[]";
String sb = "";
sb = sb + "[";
for (;;) {
E e = i.next();
sb = sb + (e == this ? "(this Collection)" : e);
if (! i.hasNext()) {
sb = sb + "]";
return sb;
}
sb = sb + ", ";
}
}
}
/*
* Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the {@link List}
* interface to minimize the effort required to implement this interface
* backed by a "random access" data store (such as an array). For sequential
* access data (such as a linked list), {@link AbstractSequentialList} should
* be used in preference to this class.
*
* To implement an unmodifiable list, the programmer needs only to extend
* this class and provide implementations for the {@link #get(int)} and
* {@link List#size() size()} methods.
*
*
To implement a modifiable list, the programmer must additionally
* override the {@link #set(int, Object) set(int, E)} method (which otherwise
* throws an {@code UnsupportedOperationException}). If the list is
* variable-size the programmer must additionally override the
* {@link #add(int, Object) add(int, E)} and {@link #remove(int)} methods.
*
*
The programmer should generally provide a void (no argument) and collection
* constructor, as per the recommendation in the {@link Collection} interface
* specification.
*
*
Unlike the other abstract collection implementations, the programmer does
* not have to provide an iterator implementation; the iterator and
* list iterator are implemented by this class, on top of the "random access"
* methods:
* {@link #get(int)},
* {@link #set(int, Object) set(int, E)},
* {@link #add(int, Object) add(int, E)} and
* {@link #remove(int)}.
*
*
The documentation for each non-abstract method in this class describes its
* implementation in detail. Each of these methods may be overridden if the
* collection being implemented admits a more efficient implementation.
*
*
This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @since 1.2
*/
public abstract class AbstractList extends AbstractCollection implements List {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractList() {
}
/**
* Appends the specified element to the end of this list (optional
* operation).
*
* Lists that support this operation may place limitations on what
* elements may be added to this list. In particular, some
* lists will refuse to add null elements, and others will impose
* restrictions on the type of elements that may be added. List
* classes should clearly specify in their documentation any restrictions
* on what elements may be added.
*
*
This implementation calls {@code add(size(), e)}.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless
* {@link #add(int, Object) add(int, E)} is overridden.
*
* @param e element to be appended to this list
* @return {@code true} (as specified by {@link Collection#add})
* @throws UnsupportedOperationException if the {@code add} operation
* is not supported by this list
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this list
*/
public boolean add(E e) {
add(size(), e);
return true;
}
/**
* {@inheritDoc}
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
abstract public E get(int index);
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
throw new UnsupportedOperationException();
}
// Search Operations
/**
* {@inheritDoc}
*
*
This implementation first gets a list iterator (with
* {@code listIterator()}). Then, it iterates over the list until the
* specified element is found or the end of the list is reached.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public int indexOf(Object o) {
ListIterator e = listIterator();
if (o==null) {
while (e.hasNext())
if (e.next()==null)
return e.previousIndex();
} else {
while (e.hasNext())
if (o.equals(e.next()))
return e.previousIndex();
}
return -1;
}
/**
* {@inheritDoc}
*
* This implementation first gets a list iterator that points to the end
* of the list (with {@code listIterator(size())}). Then, it iterates
* backwards over the list until the specified element is found, or the
* beginning of the list is reached.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public int lastIndexOf(Object o) {
ListIterator e = listIterator(size());
if (o==null) {
while (e.hasPrevious())
if (e.previous()==null)
return e.nextIndex();
} else {
while (e.hasPrevious())
if (o.equals(e.previous()))
return e.nextIndex();
}
return -1;
}
// Bulk Operations
/**
* Removes all of the elements from this list (optional operation).
* The list will be empty after this call returns.
*
* This implementation calls {@code removeRange(0, size())}.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless {@code remove(int
* index)} or {@code removeRange(int fromIndex, int toIndex)} is
* overridden.
*
* @throws UnsupportedOperationException if the {@code clear} operation
* is not supported by this list
*/
public void clear() {
removeRange(0, size());
}
/**
* {@inheritDoc}
*
*
This implementation gets an iterator over the specified collection
* and iterates over it, inserting the elements obtained from the
* iterator into this list at the appropriate position, one at a time,
* using {@code add(int, E)}.
* Many implementations will override this method for efficiency.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless
* {@link #add(int, Object) add(int, E)} is overridden.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public boolean addAll(int index, Collection c) {
rangeCheckForAdd(index);
boolean modified = false;
Iterator e = c.iterator();
while (e.hasNext()) {
add(index++, e.next());
modified = true;
}
return modified;
}
// Iterators
/**
* Returns an iterator over the elements in this list in proper sequence.
*
*
This implementation returns a straightforward implementation of the
* iterator interface, relying on the backing list's {@code size()},
* {@code get(int)}, and {@code remove(int)} methods.
*
*
Note that the iterator returned by this method will throw an
* {@link UnsupportedOperationException} in response to its
* {@code remove} method unless the list's {@code remove(int)} method is
* overridden.
*
*
This implementation can be made to throw runtime exceptions in the
* face of concurrent modification, as described in the specification
* for the (protected) {@link #modCount} field.
*
* @return an iterator over the elements in this list in proper sequence
*/
public Iterator iterator() {
return new Itr();
}
/**
* {@inheritDoc}
*
* This implementation returns {@code listIterator(0)}.
*
* @see #listIterator(int)
*/
public ListIterator listIterator() {
return listIterator(0);
}
/**
* {@inheritDoc}
*
* This implementation returns a straightforward implementation of the
* {@code ListIterator} interface that extends the implementation of the
* {@code Iterator} interface returned by the {@code iterator()} method.
* The {@code ListIterator} implementation relies on the backing list's
* {@code get(int)}, {@code set(int, E)}, {@code add(int, E)}
* and {@code remove(int)} methods.
*
*
Note that the list iterator returned by this implementation will
* throw an {@link UnsupportedOperationException} in response to its
* {@code remove}, {@code set} and {@code add} methods unless the
* list's {@code remove(int)}, {@code set(int, E)}, and
* {@code add(int, E)} methods are overridden.
*
*
This implementation can be made to throw runtime exceptions in the
* face of concurrent modification, as described in the specification for
* the (protected) {@link #modCount} field.
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public ListIterator listIterator(final int index) {
rangeCheckForAdd(index);
return new ListItr(index);
}
private class Itr implements Iterator {
/**
* Index of element to be returned by subsequent call to next.
*/
int cursor = 0;
/**
* Index of element returned by most recent call to next or
* previous. Reset to -1 if this element is deleted by a call
* to remove.
*/
int lastRet = -1;
/**
* The modCount value that the iterator believes that the backing
* List should have. If this expectation is violated, the iterator
* has detected concurrent modification.
*/
int expectedModCount = modCount;
public boolean hasNext() {
return cursor != size();
}
public E next() {
checkForComodification();
try {
int i = cursor;
E next = get(i);
lastRet = i;
cursor = i + 1;
return next;
} catch (IndexOutOfBoundsException e) {
checkForComodification();
throw new NoSuchElementException();
}
}
public void remove() {
if (lastRet < 0)
throw new IllegalStateException();
checkForComodification();
try {
AbstractList.this.remove(lastRet);
if (lastRet < cursor)
cursor--;
lastRet = -1;
expectedModCount = modCount;
} catch (IndexOutOfBoundsException e) {
throw new ConcurrentModificationException();
}
}
final void checkForComodification() {
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
}
}
private class ListItr extends Itr implements ListIterator {
ListItr(int index) {
cursor = index;
}
public boolean hasPrevious() {
return cursor != 0;
}
public E previous() {
checkForComodification();
try {
int i = cursor - 1;
E previous = get(i);
lastRet = cursor = i;
return previous;
} catch (IndexOutOfBoundsException e) {
checkForComodification();
throw new NoSuchElementException();
}
}
public int nextIndex() {
return cursor;
}
public int previousIndex() {
return cursor-1;
}
public void set(E e) {
if (lastRet < 0)
throw new IllegalStateException();
checkForComodification();
try {
AbstractList.this.set(lastRet, e);
expectedModCount = modCount;
} catch (IndexOutOfBoundsException ex) {
throw new ConcurrentModificationException();
}
}
public void add(E e) {
checkForComodification();
try {
int i = cursor;
AbstractList.this.add(i, e);
lastRet = -1;
cursor = i + 1;
expectedModCount = modCount;
} catch (IndexOutOfBoundsException ex) {
throw new ConcurrentModificationException();
}
}
}
/**
* {@inheritDoc}
*
* This implementation returns a list that subclasses
* {@code AbstractList}. The subclass stores, in private fields, the
* offset of the subList within the backing list, the size of the subList
* (which can change over its lifetime), and the expected
* {@code modCount} value of the backing list. There are two variants
* of the subclass, one of which implements {@code RandomAccess}.
* If this list implements {@code RandomAccess} the returned list will
* be an instance of the subclass that implements {@code RandomAccess}.
*
*
The subclass's {@code set(int, E)}, {@code get(int)},
* {@code add(int, E)}, {@code remove(int)}, {@code addAll(int,
* Collection)} and {@code removeRange(int, int)} methods all
* delegate to the corresponding methods on the backing abstract list,
* after bounds-checking the index and adjusting for the offset. The
* {@code addAll(Collection c)} method merely returns {@code addAll(size,
* c)}.
*
*
The {@code listIterator(int)} method returns a "wrapper object"
* over a list iterator on the backing list, which is created with the
* corresponding method on the backing list. The {@code iterator} method
* merely returns {@code listIterator()}, and the {@code size} method
* merely returns the subclass's {@code size} field.
*
*
All methods first check to see if the actual {@code modCount} of
* the backing list is equal to its expected value, and throw a
* {@code ConcurrentModificationException} if it is not.
*
* @throws IndexOutOfBoundsException if an endpoint index value is out of range
* {@code (fromIndex < 0 || toIndex > size)}
* @throws IllegalArgumentException if the endpoint indices are out of order
* {@code (fromIndex > toIndex)}
*/
public List subList(int fromIndex, int toIndex) {
return (this instanceof RandomAccess ?
new RandomAccessSubList(this, fromIndex, toIndex) :
new SubList(this, fromIndex, toIndex));
}
// Comparison and hashing
/**
* Compares the specified object with this list for equality. Returns
* {@code true} if and only if the specified object is also a list, both
* lists have the same size, and all corresponding pairs of elements in
* the two lists are equal. (Two elements {@code e1} and
* {@code e2} are equal if {@code (e1==null ? e2==null :
* e1.equals(e2))}.) In other words, two lists are defined to be
* equal if they contain the same elements in the same order.
*
* This implementation first checks if the specified object is this
* list. If so, it returns {@code true}; if not, it checks if the
* specified object is a list. If not, it returns {@code false}; if so,
* it iterates over both lists, comparing corresponding pairs of elements.
* If any comparison returns {@code false}, this method returns
* {@code false}. If either iterator runs out of elements before the
* other it returns {@code false} (as the lists are of unequal length);
* otherwise it returns {@code true} when the iterations complete.
*
* @param o the object to be compared for equality with this list
* @return {@code true} if the specified object is equal to this list
*/
public boolean equals(Object o) {
if (o == this)
return true;
if (!(o instanceof List))
return false;
ListIterator e1 = listIterator();
ListIterator e2 = ((List) o).listIterator();
while(e1.hasNext() && e2.hasNext()) {
E o1 = e1.next();
Object o2 = e2.next();
if (!(o1==null ? o2==null : o1.equals(o2)))
return false;
}
return !(e1.hasNext() || e2.hasNext());
}
/**
* Returns the hash code value for this list.
*
* This implementation uses exactly the code that is used to define the
* list hash function in the documentation for the {@link List#hashCode}
* method.
*
* @return the hash code value for this list
*/
public int hashCode() {
int hashCode = 1;
Iterator it = this.iterator();
while (it.hasNext()) {
E e = it.next();
hashCode = 31*hashCode + (e==null ? 0 : e.hashCode());
}
return hashCode;
}
/**
* Removes from this list all of the elements whose index is between
* {@code fromIndex}, inclusive, and {@code toIndex}, exclusive.
* Shifts any succeeding elements to the left (reduces their index).
* This call shortens the list by {@code (toIndex - fromIndex)} elements.
* (If {@code toIndex==fromIndex}, this operation has no effect.)
*
* This method is called by the {@code clear} operation on this list
* and its subLists. Overriding this method to take advantage of
* the internals of the list implementation can substantially
* improve the performance of the {@code clear} operation on this list
* and its subLists.
*
*
This implementation gets a list iterator positioned before
* {@code fromIndex}, and repeatedly calls {@code ListIterator.next}
* followed by {@code ListIterator.remove} until the entire range has
* been removed. Note: if {@code ListIterator.remove} requires linear
* time, this implementation requires quadratic time.
*
* @param fromIndex index of first element to be removed
* @param toIndex index after last element to be removed
*/
protected void removeRange(int fromIndex, int toIndex) {
ListIterator it = listIterator(fromIndex);
for (int i=0, n=toIndex-fromIndex; istructurally modified.
* Structural modifications are those that change the size of the
* list, or otherwise perturb it in such a fashion that iterations in
* progress may yield incorrect results.
*
* This field is used by the iterator and list iterator implementation
* returned by the {@code iterator} and {@code listIterator} methods.
* If the value of this field changes unexpectedly, the iterator (or list
* iterator) will throw a {@code ConcurrentModificationException} in
* response to the {@code next}, {@code remove}, {@code previous},
* {@code set} or {@code add} operations. This provides
* fail-fast behavior, rather than non-deterministic behavior in
* the face of concurrent modification during iteration.
*
*
Use of this field by subclasses is optional. If a subclass
* wishes to provide fail-fast iterators (and list iterators), then it
* merely has to increment this field in its {@code add(int, E)} and
* {@code remove(int)} methods (and any other methods that it overrides
* that result in structural modifications to the list). A single call to
* {@code add(int, E)} or {@code remove(int)} must add no more than
* one to this field, or the iterators (and list iterators) will throw
* bogus {@code ConcurrentModificationExceptions}. If an implementation
* does not wish to provide fail-fast iterators, this field may be
* ignored.
*/
protected transient int modCount = 0;
private void rangeCheckForAdd(int index) {
if (index < 0 || index > size())
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private String outOfBoundsMsg(int index) {
return "";
}
}
class SubList extends AbstractList {
private final AbstractList l;
private final int offset;
private int size;
SubList(AbstractList list, int fromIndex, int toIndex) {
if (fromIndex < 0)
throw new IndexOutOfBoundsException();
if (toIndex > list.size())
throw new IndexOutOfBoundsException();
if (fromIndex > toIndex)
throw new IllegalArgumentException();
l = list;
offset = fromIndex;
size = toIndex - fromIndex;
this.modCount = l.modCount;
}
public E set(int index, E element) {
rangeCheck(index);
checkForComodification();
return l.set(index+offset, element);
}
public E get(int index) {
rangeCheck(index);
checkForComodification();
return l.get(index+offset);
}
public int size() {
checkForComodification();
return size;
}
public void add(int index, E element) {
rangeCheckForAdd(index);
checkForComodification();
l.add(index+offset, element);
this.modCount = l.modCount;
size++;
}
public E remove(int index) {
rangeCheck(index);
checkForComodification();
E result = l.remove(index+offset);
this.modCount = l.modCount;
size--;
return result;
}
protected void removeRange(int fromIndex, int toIndex) {
checkForComodification();
l.removeRange(fromIndex+offset, toIndex+offset);
this.modCount = l.modCount;
size -= (toIndex-fromIndex);
}
public boolean addAll(Collection c) {
return addAll(size, c);
}
public boolean addAll(int index, Collection c) {
rangeCheckForAdd(index);
int cSize = c.size();
if (cSize==0)
return false;
checkForComodification();
l.addAll(offset+index, c);
this.modCount = l.modCount;
size += cSize;
return true;
}
public Iterator iterator() {
return listIterator();
}
public ListIterator listIterator(final int index) {
checkForComodification();
rangeCheckForAdd(index);
return new ListIterator() {
private final ListIterator i = l.listIterator(index+offset);
public boolean hasNext() {
return nextIndex() < size;
}
public E next() {
if (hasNext())
return i.next();
else
throw new NoSuchElementException();
}
public boolean hasPrevious() {
return previousIndex() >= 0;
}
public E previous() {
if (hasPrevious())
return i.previous();
else
throw new NoSuchElementException();
}
public int nextIndex() {
return i.nextIndex() - offset;
}
public int previousIndex() {
return i.previousIndex() - offset;
}
public void remove() {
i.remove();
SubList.this.modCount = l.modCount;
size--;
}
public void set(E e) {
i.set(e);
}
public void add(E e) {
i.add(e);
SubList.this.modCount = l.modCount;
size++;
}
};
}
public List subList(int fromIndex, int toIndex) {
return new SubList(this, fromIndex, toIndex);
}
private void rangeCheck(int index) {
if (index < 0 || index >= size)
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private void rangeCheckForAdd(int index) {
if (index < 0 || index > size)
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private String outOfBoundsMsg(int index) {
return "";
}
private void checkForComodification() {
if (this.modCount != l.modCount)
throw new ConcurrentModificationException();
}
}
class RandomAccessSubList extends SubList implements RandomAccess {
RandomAccessSubList(AbstractList list, int fromIndex, int toIndex) {
super(list, fromIndex, toIndex);
}
public List subList(int fromIndex, int toIndex) {
return new RandomAccessSubList(this, fromIndex, toIndex);
}
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the List
* interface to minimize the effort required to implement this interface
* backed by a "sequential access" data store (such as a linked list). For
* random access data (such as an array), AbstractList should be used
* in preference to this class.
*
* This class is the opposite of the AbstractList class in the sense
* that it implements the "random access" methods (get(int index),
* set(int index, E element), add(int index, E element) and
* remove(int index)) on top of the list's list iterator, instead of
* the other way around.
*
* To implement a list the programmer needs only to extend this class and
* provide implementations for the listIterator and size
* methods. For an unmodifiable list, the programmer need only implement the
* list iterator's hasNext, next, hasPrevious,
* previous and index methods.
*
* For a modifiable list the programmer should additionally implement the list
* iterator's set method. For a variable-size list the programmer
* should additionally implement the list iterator's remove and
* add methods.
*
* The programmer should generally provide a void (no argument) and collection
* constructor, as per the recommendation in the Collection interface
* specification.
*
* This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Collection
* @see List
* @see AbstractList
* @see AbstractCollection
* @since 1.2
*/
public abstract class AbstractSequentialList extends AbstractList {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractSequentialList() {
}
/**
* Returns the element at the specified position in this list.
*
* This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it gets
* the element using ListIterator.next and returns it.
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E get(int index) {
try {
return listIterator(index).next();
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Replaces the element at the specified position in this list with the
* specified element (optional operation).
*
*
This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it gets
* the current element using ListIterator.next and replaces it
* with ListIterator.set.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the set operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
try {
ListIterator e = listIterator(index);
E oldVal = e.next();
e.set(element);
return oldVal;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Inserts the specified element at the specified position in this list
* (optional operation). Shifts the element currently at that position
* (if any) and any subsequent elements to the right (adds one to their
* indices).
*
* This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it
* inserts the specified element with ListIterator.add.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the add operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
try {
listIterator(index).add(element);
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Removes the element at the specified position in this list (optional
* operation). Shifts any subsequent elements to the left (subtracts one
* from their indices). Returns the element that was removed from the
* list.
*
*
This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it removes
* the element with ListIterator.remove.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the remove operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
try {
ListIterator e = listIterator(index);
E outCast = e.next();
e.remove();
return outCast;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
// Bulk Operations
/**
* Inserts all of the elements in the specified collection into this
* list at the specified position (optional operation). Shifts the
* element currently at that position (if any) and any subsequent
* elements to the right (increases their indices). The new elements
* will appear in this list in the order that they are returned by the
* specified collection's iterator. The behavior of this operation is
* undefined if the specified collection is modified while the
* operation is in progress. (Note that this will occur if the specified
* collection is this list, and it's nonempty.)
*
* This implementation gets an iterator over the specified collection and
* a list iterator over this list pointing to the indexed element (with
* listIterator(index)). Then, it iterates over the specified
* collection, inserting the elements obtained from the iterator into this
* list, one at a time, using ListIterator.add followed by
* ListIterator.next (to skip over the added element).
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator returned by
* the listIterator method does not implement the add
* operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public boolean addAll(int index, Collection c) {
try {
boolean modified = false;
ListIterator e1 = listIterator(index);
Iterator e2 = c.iterator();
while (e2.hasNext()) {
e1.add(e2.next());
modified = true;
}
return modified;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
// Iterators
/**
* Returns an iterator over the elements in this list (in proper
* sequence).
*
* This implementation merely returns a list iterator over the list.
*
* @return an iterator over the elements in this list (in proper sequence)
*/
public Iterator iterator() {
return listIterator();
}
/**
* Returns a list iterator over the elements in this list (in proper
* sequence).
*
* @param index index of first element to be returned from the list
* iterator (by a call to the next method)
* @return a list iterator over the elements in this list (in proper
* sequence)
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public abstract ListIterator listIterator(int index);
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* The root interface in the collection hierarchy. A collection
* represents a group of objects, known as its elements. Some
* collections allow duplicate elements and others do not. Some are ordered
* and others unordered. The JDK does not provide any direct
* implementations of this interface: it provides implementations of more
* specific subinterfaces like Set and List. This interface
* is typically used to pass collections around and manipulate them where
* maximum generality is desired.
*
* Bags or multisets (unordered collections that may contain
* duplicate elements) should implement this interface directly.
*
*
All general-purpose Collection implementation classes (which
* typically implement Collection indirectly through one of its
* subinterfaces) should provide two "standard" constructors: a void (no
* arguments) constructor, which creates an empty collection, and a
* constructor with a single argument of type Collection, which
* creates a new collection with the same elements as its argument. In
* effect, the latter constructor allows the user to copy any collection,
* producing an equivalent collection of the desired implementation type.
* There is no way to enforce this convention (as interfaces cannot contain
* constructors) but all of the general-purpose Collection
* implementations in the Java platform libraries comply.
*
*
The "destructive" methods contained in this interface, that is, the
* methods that modify the collection on which they operate, are specified to
* throw UnsupportedOperationException if this collection does not
* support the operation. If this is the case, these methods may, but are not
* required to, throw an UnsupportedOperationException if the
* invocation would have no effect on the collection. For example, invoking
* the {@link #addAll(Collection)} method on an unmodifiable collection may,
* but is not required to, throw the exception if the collection to be added
* is empty.
*
*
Some collection implementations have restrictions on the elements that
* they may contain. For example, some implementations prohibit null elements,
* and some have restrictions on the types of their elements. Attempting to
* add an ineligible element throws an unchecked exception, typically
* NullPointerException or ClassCastException. Attempting
* to query the presence of an ineligible element may throw an exception,
* or it may simply return false; some implementations will exhibit the former
* behavior and some will exhibit the latter. More generally, attempting an
* operation on an ineligible element whose completion would not result in
* the insertion of an ineligible element into the collection may throw an
* exception or it may succeed, at the option of the implementation.
* Such exceptions are marked as "optional" in the specification for this
* interface.
*
*
It is up to each collection to determine its own synchronization
* policy. In the absence of a stronger guarantee by the
* implementation, undefined behavior may result from the invocation
* of any method on a collection that is being mutated by another
* thread; this includes direct invocations, passing the collection to
* a method that might perform invocations, and using an existing
* iterator to examine the collection.
*
*
Many methods in Collections Framework interfaces are defined in
* terms of the {@link Object#equals(Object) equals} method. For example,
* the specification for the {@link #contains(Object) contains(Object o)}
* method says: "returns true if and only if this collection
* contains at least one element e such that
* (o==null ? e==null : o.equals(e))." This specification should
* not be construed to imply that invoking Collection.contains
* with a non-null argument o will cause o.equals(e) to be
* invoked for any element e. Implementations are free to implement
* optimizations whereby the equals invocation is avoided, for
* example, by first comparing the hash codes of the two elements. (The
* {@link Object#hashCode()} specification guarantees that two objects with
* unequal hash codes cannot be equal.) More generally, implementations of
* the various Collections Framework interfaces are free to take advantage of
* the specified behavior of underlying {@link Object} methods wherever the
* implementor deems it appropriate.
*
*
This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Set
* @see List
* @see Map
* @see SortedSet
* @see SortedMap
* @see HashSet
* @see TreeSet
* @see ArrayList
* @see LinkedList
* @see Vector
* @see Collections
* @see Arrays
* @see AbstractCollection
* @since 1.2
*/
public interface Collection {
// Query Operations
/**
* Returns the number of elements in this collection. If this collection
* contains more than Integer.MAX_VALUE elements, returns
* Integer.MAX_VALUE.
*
* @return the number of elements in this collection
*/
int size();
/**
* Returns true if this collection contains no elements.
*
* @return true if this collection contains no elements
*/
boolean isEmpty();
/**
* Returns true if this collection contains the specified element.
* More formally, returns true if and only if this collection
* contains at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this collection is to be tested
* @return true if this collection contains the specified
* element
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection (optional)
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements (optional)
*/
boolean contains(Object o);
/**
* Returns an iterator over the elements in this collection. There are no
* guarantees concerning the order in which the elements are returned
* (unless this collection is an instance of some class that provides a
* guarantee).
*
* @return an Iterator over the elements in this collection
*/
Iterator iterator();
// Modification Operations
/**
* Ensures that this collection contains the specified element (optional
* operation). Returns true if this collection changed as a
* result of the call. (Returns false if this collection does
* not permit duplicates and already contains the specified element.)
*
* Collections that support this operation may place limitations on what
* elements may be added to this collection. In particular, some
* collections will refuse to add null elements, and others will
* impose restrictions on the type of elements that may be added.
* Collection classes should clearly specify in their documentation any
* restrictions on what elements may be added.
*
* If a collection refuses to add a particular element for any reason
* other than that it already contains the element, it must throw
* an exception (rather than returning false). This preserves
* the invariant that a collection always contains the specified element
* after this call returns.
*
* @param e element whose presence in this collection is to be ensured
* @return true if this collection changed as a result of the
* call
* @throws UnsupportedOperationException if the add operation
* is not supported by this collection
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this collection
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements
* @throws IllegalArgumentException if some property of the element
* prevents it from being added to this collection
* @throws IllegalStateException if the element cannot be added at this
* time due to insertion restrictions
*/
boolean add(E e);
/**
* Removes a single instance of the specified element from this
* collection, if it is present (optional operation). More formally,
* removes an element e such that
* (o==null ? e==null : o.equals(e)), if
* this collection contains one or more such elements. Returns
* true if this collection contained the specified element (or
* equivalently, if this collection changed as a result of the call).
*
* @param o element to be removed from this collection, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection (optional)
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements (optional)
* @throws UnsupportedOperationException if the remove operation
* is not supported by this collection
*/
boolean remove(Object o);
// Bulk Operations
/**
* Returns true if this collection contains all of the elements
* in the specified collection.
*
* @param c collection to be checked for containment in this collection
* @return true if this collection contains all of the elements
* in the specified collection
* @throws ClassCastException if the types of one or more elements
* in the specified collection are incompatible with this
* collection (optional)
* @throws NullPointerException if the specified collection contains one
* or more null elements and this collection does not permit null
* elements (optional), or if the specified collection is null
* @see #contains(Object)
*/
boolean containsAll(Collection c);
/**
* Adds all of the elements in the specified collection to this collection
* (optional operation). The behavior of this operation is undefined if
* the specified collection is modified while the operation is in progress.
* (This implies that the behavior of this call is undefined if the
* specified collection is this collection, and this collection is
* nonempty.)
*
* @param c collection containing elements to be added to this collection
* @return true if this collection changed as a result of the call
* @throws UnsupportedOperationException if the addAll operation
* is not supported by this collection
* @throws ClassCastException if the class of an element of the specified
* collection prevents it from being added to this collection
* @throws NullPointerException if the specified collection contains a
* null element and this collection does not permit null elements,
* or if the specified collection is null
* @throws IllegalArgumentException if some property of an element of the
* specified collection prevents it from being added to this
* collection
* @throws IllegalStateException if not all the elements can be added at
* this time due to insertion restrictions
* @see #add(Object)
*/
boolean addAll(Collection c);
/**
* Removes all of this collection's elements that are also contained in the
* specified collection (optional operation). After this call returns,
* this collection will contain no elements in common with the specified
* collection.
*
* @param c collection containing elements to be removed from this collection
* @return true if this collection changed as a result of the
* call
* @throws UnsupportedOperationException if the removeAll method
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection (optional)
* @throws NullPointerException if this collection contains one or more
* null elements and the specified collection does not support
* null elements (optional), or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean removeAll(Collection c);
/**
* Retains only the elements in this collection that are contained in the
* specified collection (optional operation). In other words, removes from
* this collection all of its elements that are not contained in the
* specified collection.
*
* @param c collection containing elements to be retained in this collection
* @return true if this collection changed as a result of the call
* @throws UnsupportedOperationException if the retainAll operation
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection (optional)
* @throws NullPointerException if this collection contains one or more
* null elements and the specified collection does not permit null
* elements (optional), or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean retainAll(Collection c);
/**
* Removes all of the elements from this collection (optional operation).
* The collection will be empty after this method returns.
*
* @throws UnsupportedOperationException if the clear operation
* is not supported by this collection
*/
void clear();
// Comparison and hashing
/**
* Compares the specified object with this collection for equality.
*
* While the Collection interface adds no stipulations to the
* general contract for the Object.equals, programmers who
* implement the Collection interface "directly" (in other words,
* create a class that is a Collection but is not a Set
* or a List) must exercise care if they choose to override the
* Object.equals. It is not necessary to do so, and the simplest
* course of action is to rely on Object's implementation, but
* the implementor may wish to implement a "value comparison" in place of
* the default "reference comparison." (The List and
* Set interfaces mandate such value comparisons.)
*
* The general contract for the Object.equals method states that
* equals must be symmetric (in other words, a.equals(b) if and
* only if b.equals(a)). The contracts for List.equals
* and Set.equals state that lists are only equal to other lists,
* and sets to other sets. Thus, a custom equals method for a
* collection class that implements neither the List nor
* Set interface must return false when this collection
* is compared to any list or set. (By the same logic, it is not possible
* to write a class that correctly implements both the Set and
* List interfaces.)
*
* @param o object to be compared for equality with this collection
* @return true if the specified object is equal to this
* collection
*
* @see Object#equals(Object)
* @see Set#equals(Object)
* @see List#equals(Object)
*/
boolean equals(Object o);
/**
* Returns the hash code value for this collection. While the
* Collection interface adds no stipulations to the general
* contract for the Object.hashCode method, programmers should
* take note that any class that overrides the Object.equals
* method must also override the Object.hashCode method in order
* to satisfy the general contract for the Object.hashCodemethod.
* In particular, c1.equals(c2) implies that
* c1.hashCode()==c2.hashCode().
*
* @return the hash code value for this collection
*
* @see Object#hashCode()
* @see Object#equals(Object)
*/
int hashCode();
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This exception may be thrown by methods that have detected concurrent
* modification of an object when such modification is not permissible.
*
* For example, it is not generally permissible for one thread to modify a Collection
* while another thread is iterating over it. In general, the results of the
* iteration are undefined under these circumstances. Some Iterator
* implementations (including those of all the general purpose collection implementations
* provided by the JRE) may choose to throw this exception if this behavior is
* detected. Iterators that do this are known as fail-fast iterators,
* as they fail quickly and cleanly, rather that risking arbitrary,
* non-deterministic behavior at an undetermined time in the future.
*
* Note that this exception does not always indicate that an object has
* been concurrently modified by a different thread. If a single
* thread issues a sequence of method invocations that violates the
* contract of an object, the object may throw this exception. For
* example, if a thread modifies a collection directly while it is
* iterating over the collection with a fail-fast iterator, the iterator
* will throw this exception.
*
*
Note that fail-fast behavior cannot be guaranteed as it is, generally
* speaking, impossible to make any hard guarantees in the presence of
* unsynchronized concurrent modification. Fail-fast operations
* throw ConcurrentModificationException on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: ConcurrentModificationException
* should be used only to detect bugs.
*
* @author Josh Bloch
* @see Collection
* @see Iterator
* @see ListIterator
* @see Vector
* @see LinkedList
* @see HashSet
* @see Hashtable
* @see TreeMap
* @see AbstractList
* @since 1.2
*/
public class ConcurrentModificationException extends RuntimeException {
/**
* Constructs a ConcurrentModificationException with no
* detail message.
*/
public ConcurrentModificationException() {
}
/**
* Constructs a ConcurrentModificationException with the
* specified detail message.
*
* @param message the detail message pertaining to this exception.
*/
public ConcurrentModificationException(String message) {
super(message);
}
}
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea and Josh Bloch with assistance from members of
* JCP JSR-166 Expert Group and released to the public domain, as explained
* at http://creativecommons.org/licenses/publicdomain
*/
package javaUtilEx;
/**
* A linear collection that supports element insertion and removal at
* both ends. The name deque is short for "double ended queue"
* and is usually pronounced "deck". Most Deque
* implementations place no fixed limits on the number of elements
* they may contain, but this interface supports capacity-restricted
* deques as well as those with no fixed size limit.
*
*
This interface defines methods to access the elements at both
* ends of the deque. Methods are provided to insert, remove, and
* examine the element. Each of these methods exists in two forms:
* one throws an exception if the operation fails, the other returns a
* special value (either null or false, depending on
* the operation). The latter form of the insert operation is
* designed specifically for use with capacity-restricted
* Deque implementations; in most implementations, insert
* operations cannot fail.
*
*
The twelve methods described above are summarized in the
* following table:
*
*
*
*
* |
* First Element (Head) |
* Last Element (Tail) |
*
*
* |
* Throws exception |
* Special value |
* Throws exception |
* Special value |
*
*
* | Insert |
* {@link #addFirst addFirst(e)} |
* {@link #offerFirst offerFirst(e)} |
* {@link #addLast addLast(e)} |
* {@link #offerLast offerLast(e)} |
*
*
* | Remove |
* {@link #removeFirst removeFirst()} |
* {@link #pollFirst pollFirst()} |
* {@link #removeLast removeLast()} |
* {@link #pollLast pollLast()} |
*
*
* | Examine |
* {@link #getFirst getFirst()} |
* {@link #peekFirst peekFirst()} |
* {@link #getLast getLast()} |
* {@link #peekLast peekLast()} |
*
*
*
* This interface extends the {@link Queue} interface. When a deque is
* used as a queue, FIFO (First-In-First-Out) behavior results. Elements are
* added at the end of the deque and removed from the beginning. The methods
* inherited from the Queue interface are precisely equivalent to
* Deque methods as indicated in the following table:
*
*
*
*
* | Queue Method |
* Equivalent Deque Method |
*
*
* | {@link java.util.Queue#add add(e)} |
* {@link #addLast addLast(e)} |
*
*
* | {@link java.util.Queue#offer offer(e)} |
* {@link #offerLast offerLast(e)} |
*
*
* | {@link java.util.Queue#remove remove()} |
* {@link #removeFirst removeFirst()} |
*
*
* | {@link java.util.Queue#poll poll()} |
* {@link #pollFirst pollFirst()} |
*
*
* | {@link java.util.Queue#element element()} |
* {@link #getFirst getFirst()} |
*
*
* | {@link java.util.Queue#peek peek()} |
* {@link #peek peekFirst()} |
*
*
*
* Deques can also be used as LIFO (Last-In-First-Out) stacks. This
* interface should be used in preference to the legacy {@link Stack} class.
* When a deque is used as a stack, elements are pushed and popped from the
* beginning of the deque. Stack methods are precisely equivalent to
* Deque methods as indicated in the table below:
*
*
*
*
* | Stack Method |
* Equivalent Deque Method |
*
*
* | {@link #push push(e)} |
* {@link #addFirst addFirst(e)} |
*
*
* | {@link #pop pop()} |
* {@link #removeFirst removeFirst()} |
*
*
* | {@link #peek peek()} |
* {@link #peekFirst peekFirst()} |
*
*
*
* Note that the {@link #peek peek} method works equally well when
* a deque is used as a queue or a stack; in either case, elements are
* drawn from the beginning of the deque.
*
*
This interface provides two methods to remove interior
* elements, {@link #removeFirstOccurrence removeFirstOccurrence} and
* {@link #removeLastOccurrence removeLastOccurrence}.
*
*
Unlike the {@link List} interface, this interface does not
* provide support for indexed access to elements.
*
*
While Deque implementations are not strictly required
* to prohibit the insertion of null elements, they are strongly
* encouraged to do so. Users of any Deque implementations
* that do allow null elements are strongly encouraged not to
* take advantage of the ability to insert nulls. This is so because
* null is used as a special return value by various methods
* to indicated that the deque is empty.
*
*
Deque implementations generally do not define
* element-based versions of the equals and hashCode
* methods, but instead inherit the identity-based versions from class
* Object.
*
*
This interface is a member of the Java Collections
* Framework.
*
* @author Doug Lea
* @author Josh Bloch
* @since 1.6
* @param the type of elements held in this collection
*/
public interface Deque extends Queue {
/**
* Inserts the specified element at the front of this deque if it is
* possible to do so immediately without violating capacity restrictions.
* When using a capacity-restricted deque, it is generally preferable to
* use method {@link #offerFirst}.
*
* @param e the element to add
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void addFirst(E e);
/**
* Inserts the specified element at the end of this deque if it is
* possible to do so immediately without violating capacity restrictions.
* When using a capacity-restricted deque, it is generally preferable to
* use method {@link #offerLast}.
*
* This method is equivalent to {@link #add}.
*
* @param e the element to add
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void addLast(E e);
/**
* Inserts the specified element at the front of this deque unless it would
* violate capacity restrictions. When using a capacity-restricted deque,
* this method is generally preferable to the {@link #addFirst} method,
* which can fail to insert an element only by throwing an exception.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offerFirst(E e);
/**
* Inserts the specified element at the end of this deque unless it would
* violate capacity restrictions. When using a capacity-restricted deque,
* this method is generally preferable to the {@link #addLast} method,
* which can fail to insert an element only by throwing an exception.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offerLast(E e);
/**
* Retrieves and removes the first element of this deque. This method
* differs from {@link #pollFirst pollFirst} only in that it throws an
* exception if this deque is empty.
*
* @return the head of this deque
* @throws NoSuchElementException if this deque is empty
*/
E removeFirst();
/**
* Retrieves and removes the last element of this deque. This method
* differs from {@link #pollLast pollLast} only in that it throws an
* exception if this deque is empty.
*
* @return the tail of this deque
* @throws NoSuchElementException if this deque is empty
*/
E removeLast();
/**
* Retrieves and removes the first element of this deque,
* or returns null if this deque is empty.
*
* @return the head of this deque, or null if this deque is empty
*/
E pollFirst();
/**
* Retrieves and removes the last element of this deque,
* or returns null if this deque is empty.
*
* @return the tail of this deque, or null if this deque is empty
*/
E pollLast();
/**
* Retrieves, but does not remove, the first element of this deque.
*
* This method differs from {@link #peekFirst peekFirst} only in that it
* throws an exception if this deque is empty.
*
* @return the head of this deque
* @throws NoSuchElementException if this deque is empty
*/
E getFirst();
/**
* Retrieves, but does not remove, the last element of this deque.
* This method differs from {@link #peekLast peekLast} only in that it
* throws an exception if this deque is empty.
*
* @return the tail of this deque
* @throws NoSuchElementException if this deque is empty
*/
E getLast();
/**
* Retrieves, but does not remove, the first element of this deque,
* or returns null if this deque is empty.
*
* @return the head of this deque, or null if this deque is empty
*/
E peekFirst();
/**
* Retrieves, but does not remove, the last element of this deque,
* or returns null if this deque is empty.
*
* @return the tail of this deque, or null if this deque is empty
*/
E peekLast();
/**
* Removes the first occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the first element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean removeFirstOccurrence(Object o);
/**
* Removes the last occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the last element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean removeLastOccurrence(Object o);
// *** Queue methods ***
/**
* Inserts the specified element into the queue represented by this deque
* (in other words, at the tail of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and throwing an
* IllegalStateException if no space is currently available.
* When using a capacity-restricted deque, it is generally preferable to
* use {@link #offer(Object) offer}.
*
*
This method is equivalent to {@link #addLast}.
*
* @param e the element to add
* @return true (as specified by {@link Collection#add})
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean add(E e);
/**
* Inserts the specified element into the queue represented by this deque
* (in other words, at the tail of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and false if no space is currently
* available. When using a capacity-restricted deque, this method is
* generally preferable to the {@link #add} method, which can fail to
* insert an element only by throwing an exception.
*
*
This method is equivalent to {@link #offerLast}.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offer(E e);
/**
* Retrieves and removes the head of the queue represented by this deque
* (in other words, the first element of this deque).
* This method differs from {@link #poll poll} only in that it throws an
* exception if this deque is empty.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the head of the queue represented by this deque
* @throws NoSuchElementException if this deque is empty
*/
E remove();
/**
* Retrieves and removes the head of the queue represented by this deque
* (in other words, the first element of this deque), or returns
* null if this deque is empty.
*
*
This method is equivalent to {@link #pollFirst()}.
*
* @return the first element of this deque, or null if
* this deque is empty
*/
E poll();
/**
* Retrieves, but does not remove, the head of the queue represented by
* this deque (in other words, the first element of this deque).
* This method differs from {@link #peek peek} only in that it throws an
* exception if this deque is empty.
*
*
This method is equivalent to {@link #getFirst()}.
*
* @return the head of the queue represented by this deque
* @throws NoSuchElementException if this deque is empty
*/
E element();
/**
* Retrieves, but does not remove, the head of the queue represented by
* this deque (in other words, the first element of this deque), or
* returns null if this deque is empty.
*
*
This method is equivalent to {@link #peekFirst()}.
*
* @return the head of the queue represented by this deque, or
* null if this deque is empty
*/
E peek();
// *** Stack methods ***
/**
* Pushes an element onto the stack represented by this deque (in other
* words, at the head of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and throwing an
* IllegalStateException if no space is currently available.
*
*
This method is equivalent to {@link #addFirst}.
*
* @param e the element to push
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void push(E e);
/**
* Pops an element from the stack represented by this deque. In other
* words, removes and returns the first element of this deque.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the element at the front of this deque (which is the top
* of the stack represented by this deque)
* @throws NoSuchElementException if this deque is empty
*/
E pop();
// *** Collection methods ***
/**
* Removes the first occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the first element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
*
This method is equivalent to {@link #removeFirstOccurrence}.
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean remove(Object o);
/**
* Returns true if this deque contains the specified element.
* More formally, returns true if and only if this deque contains
* at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this deque is to be tested
* @return true if this deque contains the specified element
* @throws ClassCastException if the type of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean contains(Object o);
/**
* Returns the number of elements in this deque.
*
* @return the number of elements in this deque
*/
public int size();
/**
* Returns an iterator over the elements in this deque in proper sequence.
* The elements will be returned in order from first (head) to last (tail).
*
* @return an iterator over the elements in this deque in proper sequence
*/
Iterator iterator();
/**
* Returns an iterator over the elements in this deque in reverse
* sequential order. The elements will be returned in order from
* last (tail) to first (head).
*
* @return an iterator over the elements in this deque in reverse
* sequence
*/
Iterator descendingIterator();
}
/*
* Copyright 1994-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Thrown to indicate that a method has been passed an illegal or
* inappropriate argument.
*
* @author unascribed
* @see java.lang.Thread#setPriority(int)
* @since JDK1.0
*/
public
class IllegalArgumentException extends RuntimeException {
/**
* Constructs an IllegalArgumentException with no
* detail message.
*/
public IllegalArgumentException() {
super();
}
/**
* Constructs an IllegalArgumentException with the
* specified detail message.
*
* @param s the detail message.
*/
public IllegalArgumentException(String s) {
super(s);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
* Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalArgumentException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of (cause==null ? null : cause.toString()) (which
* typically contains the class and detail message of cause).
* This constructor is useful for exceptions that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalArgumentException(Throwable cause) {
super(cause);
}
private static final long serialVersionUID = -5365630128856068164L;
}
/*
* Copyright 1996-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Signals that a method has been invoked at an illegal or
* inappropriate time. In other words, the Java environment or
* Java application is not in an appropriate state for the requested
* operation.
*
* @author Jonni Kanerva
* @since JDK1.1
*/
public
class IllegalStateException extends RuntimeException {
/**
* Constructs an IllegalStateException with no detail message.
* A detail message is a String that describes this particular exception.
*/
public IllegalStateException() {
super();
}
/**
* Constructs an IllegalStateException with the specified detail
* message. A detail message is a String that describes this particular
* exception.
*
* @param s the String that contains a detailed message
*/
public IllegalStateException(String s) {
super(s);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
*
Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalStateException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of (cause==null ? null : cause.toString()) (which
* typically contains the class and detail message of cause).
* This constructor is useful for exceptions that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalStateException(Throwable cause) {
super(cause);
}
static final long serialVersionUID = -1848914673093119416L;
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* An iterator over a collection. {@code Iterator} takes the place of
* {@link Enumeration} in the Java Collections Framework. Iterators
* differ from enumerations in two ways:
*
*
* - Iterators allow the caller to remove elements from the
* underlying collection during the iteration with well-defined
* semantics.
*
- Method names have been improved.
*
*
* This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @see Collection
* @see ListIterator
* @see Iterable
* @since 1.2
*/
public interface Iterator {
/**
* Returns {@code true} if the iteration has more elements.
* (In other words, returns {@code true} if {@link #next} would
* return an element rather than throwing an exception.)
*
* @return {@code true} if the iteration has more elements
*/
boolean hasNext();
/**
* Returns the next element in the iteration.
*
* @return the next element in the iteration
* @throws NoSuchElementException if the iteration has no more elements
*/
E next();
/**
* Removes from the underlying collection the last element returned
* by this iterator (optional operation). This method can be called
* only once per call to {@link #next}. The behavior of an iterator
* is unspecified if the underlying collection is modified while the
* iteration is in progress in any way other than by calling this
* method.
*
* @throws UnsupportedOperationException if the {@code remove}
* operation is not supported by this iterator
*
* @throws IllegalStateException if the {@code next} method has not
* yet been called, or the {@code remove} method has already
* been called after the last call to the {@code next}
* method
*/
void remove();
}
package javaUtilEx;
public class juLinkedListCreateIsEmpty {
public static void main(String[] args) {
Random.args = args;
LinkedList l = createList(Random.random());
l.isEmpty();
}
public static LinkedList createList(int n) {
LinkedList l = new LinkedList();
while (n > 0) {
l.addLast(new Content(Random.random()));
n--;
}
return l;
}
}
final class Content {
int val;
public Content(int v) {
this.val = v;
}
public int hashCode() {
return val^31;
}
public boolean equals(Object o) {
if (o instanceof Content) {
return this.val == ((Content) o).val;
}
return false;
}
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Linked list implementation of the List interface. Implements all
* optional list operations, and permits all elements (including
* null). In addition to implementing the List interface,
* the LinkedList class provides uniformly named methods to
* get, remove and insert an element at the
* beginning and end of the list. These operations allow linked lists to be
* used as a stack, {@linkplain Queue queue}, or {@linkplain Deque
* double-ended queue}.
*
* The class implements the Deque interface, providing
* first-in-first-out queue operations for add,
* poll, along with other stack and deque operations.
*
* All of the operations perform as could be expected for a doubly-linked
* list. Operations that index into the list will traverse the list from
* the beginning or the end, whichever is closer to the specified index.
*
*
Note that this implementation is not synchronized.
* If multiple threads access a linked list concurrently, and at least
* one of the threads modifies the list structurally, it must be
* synchronized externally. (A structural modification is any operation
* that adds or deletes one or more elements; merely setting the value of
* an element is not a structural modification.) This is typically
* accomplished by synchronizing on some object that naturally
* encapsulates the list.
*
* If no such object exists, the list should be "wrapped" using the
* {@link Collections#synchronizedList Collections.synchronizedList}
* method. This is best done at creation time, to prevent accidental
* unsynchronized access to the list:
* List list = Collections.synchronizedList(new LinkedList(...));
*
* The iterators returned by this class's iterator and
* listIterator methods are fail-fast: if the list is
* structurally modified at any time after the iterator is created, in
* any way except through the Iterator's own remove or
* add methods, the iterator will throw a {@link
* ConcurrentModificationException}. Thus, in the face of concurrent
* modification, the iterator fails quickly and cleanly, rather than
* risking arbitrary, non-deterministic behavior at an undetermined
* time in the future.
*
*
Note that the fail-fast behavior of an iterator cannot be guaranteed
* as it is, generally speaking, impossible to make any hard guarantees in the
* presence of unsynchronized concurrent modification. Fail-fast iterators
* throw ConcurrentModificationException on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: the fail-fast behavior of iterators
* should be used only to detect bugs.
*
*
This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @see List
* @see ArrayList
* @see Vector
* @since 1.2
* @param the type of elements held in this collection
*/
public class LinkedList
extends AbstractSequentialList
implements List, Deque
{
private transient Entry header = new Entry(null, null, null);
private transient int size = 0;
/**
* Constructs an empty list.
*/
public LinkedList() {
header.next = header.previous = header;
}
/**
* Constructs a list containing the elements of the specified
* collection, in the order they are returned by the collection's
* iterator.
*
* @param c the collection whose elements are to be placed into this list
* @throws NullPointerException if the specified collection is null
*/
public LinkedList(Collection c) {
this();
addAll(c);
}
/**
* Returns the first element in this list.
*
* @return the first element in this list
* @throws NoSuchElementException if this list is empty
*/
public E getFirst() {
if (size==0)
throw new NoSuchElementException();
return header.next.element;
}
/**
* Returns the last element in this list.
*
* @return the last element in this list
* @throws NoSuchElementException if this list is empty
*/
public E getLast() {
if (size==0)
throw new NoSuchElementException();
return header.previous.element;
}
/**
* Removes and returns the first element from this list.
*
* @return the first element from this list
* @throws NoSuchElementException if this list is empty
*/
public E removeFirst() {
return remove(header.next);
}
/**
* Removes and returns the last element from this list.
*
* @return the last element from this list
* @throws NoSuchElementException if this list is empty
*/
public E removeLast() {
return remove(header.previous);
}
/**
* Inserts the specified element at the beginning of this list.
*
* @param e the element to add
*/
public void addFirst(E e) {
addBefore(e, header.next);
}
/**
* Appends the specified element to the end of this list.
*
* This method is equivalent to {@link #add}.
*
* @param e the element to add
*/
public void addLast(E e) {
addBefore(e, header);
}
/**
* Returns true if this list contains the specified element.
* More formally, returns true if and only if this list contains
* at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this list is to be tested
* @return true if this list contains the specified element
*/
public boolean contains(Object o) {
return indexOf(o) != -1;
}
/**
* Returns the number of elements in this list.
*
* @return the number of elements in this list
*/
public int size() {
return size;
}
/**
* Appends the specified element to the end of this list.
*
*
This method is equivalent to {@link #addLast}.
*
* @param e element to be appended to this list
* @return true (as specified by {@link Collection#add})
*/
public boolean add(E e) {
addBefore(e, header);
return true;
}
/**
* Removes the first occurrence of the specified element from this list,
* if it is present. If this list does not contain the element, it is
* unchanged. More formally, removes the element with the lowest index
* i such that
* (o==null ? get(i)==null : o.equals(get(i)))
* (if such an element exists). Returns true if this list
* contained the specified element (or equivalently, if this list
* changed as a result of the call).
*
* @param o element to be removed from this list, if present
* @return true if this list contained the specified element
*/
public boolean remove(Object o) {
if (o==null) {
for (Entry e = header.next; e != header; e = e.next) {
if (e.element==null) {
remove(e);
return true;
}
}
} else {
for (Entry e = header.next; e != header; e = e.next) {
if (o.equals(e.element)) {
remove(e);
return true;
}
}
}
return false;
}
/**
* Removes all of the elements from this list.
*/
public void clear() {
Entry e = header.next;
while (e != header) {
Entry next = e.next;
e.next = e.previous = null;
e.element = null;
e = next;
}
header.next = header.previous = header;
size = 0;
modCount++;
}
// Positional Access Operations
/**
* Returns the element at the specified position in this list.
*
* @param index index of the element to return
* @return the element at the specified position in this list
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E get(int index) {
return entry(index).element;
}
/**
* Replaces the element at the specified position in this list with the
* specified element.
*
* @param index index of the element to replace
* @param element element to be stored at the specified position
* @return the element previously at the specified position
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
Entry e = entry(index);
E oldVal = e.element;
e.element = element;
return oldVal;
}
/**
* Inserts the specified element at the specified position in this list.
* Shifts the element currently at that position (if any) and any
* subsequent elements to the right (adds one to their indices).
*
* @param index index at which the specified element is to be inserted
* @param element element to be inserted
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
addBefore(element, (index==size ? header : entry(index)));
}
/**
* Removes the element at the specified position in this list. Shifts any
* subsequent elements to the left (subtracts one from their indices).
* Returns the element that was removed from the list.
*
* @param index the index of the element to be removed
* @return the element previously at the specified position
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
return remove(entry(index));
}
/**
* Returns the indexed entry.
*/
private Entry entry(int index) {
if (index < 0 || index >= size)
throw new IndexOutOfBoundsException();
Entry e = header;
if (index < (size >> 1)) {
for (int i = 0; i <= index; i++)
e = e.next;
} else {
for (int i = size; i > index; i--)
e = e.previous;
}
return e;
}
// Search Operations
/**
* Returns the index of the first occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the lowest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the first occurrence of the specified element in
* this list, or -1 if this list does not contain the element
*/
public int indexOf(Object o) {
int index = 0;
if (o==null) {
for (Entry e = header.next; e != header; e = e.next) {
if (e.element==null)
return index;
index++;
}
} else {
for (Entry e = header.next; e != header; e = e.next) {
if (o.equals(e.element))
return index;
index++;
}
}
return -1;
}
/**
* Returns the index of the last occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the highest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the last occurrence of the specified element in
* this list, or -1 if this list does not contain the element
*/
public int lastIndexOf(Object o) {
int index = size;
if (o==null) {
for (Entry e = header.previous; e != header; e = e.previous) {
index--;
if (e.element==null)
return index;
}
} else {
for (Entry e = header.previous; e != header; e = e.previous) {
index--;
if (o.equals(e.element))
return index;
}
}
return -1;
}
// Queue operations.
/**
* Retrieves, but does not remove, the head (first element) of this list.
* @return the head of this list, or null if this list is empty
* @since 1.5
*/
public E peek() {
if (size==0)
return null;
return getFirst();
}
/**
* Retrieves, but does not remove, the head (first element) of this list.
* @return the head of this list
* @throws NoSuchElementException if this list is empty
* @since 1.5
*/
public E element() {
return getFirst();
}
/**
* Retrieves and removes the head (first element) of this list
* @return the head of this list, or null if this list is empty
* @since 1.5
*/
public E poll() {
if (size==0)
return null;
return removeFirst();
}
/**
* Retrieves and removes the head (first element) of this list.
*
* @return the head of this list
* @throws NoSuchElementException if this list is empty
* @since 1.5
*/
public E remove() {
return removeFirst();
}
/**
* Adds the specified element as the tail (last element) of this list.
*
* @param e the element to add
* @return true (as specified by {@link Queue#offer})
* @since 1.5
*/
public boolean offer(E e) {
return add(e);
}
// Deque operations
/**
* Inserts the specified element at the front of this list.
*
* @param e the element to insert
* @return true (as specified by {@link Deque#offerFirst})
* @since 1.6
*/
public boolean offerFirst(E e) {
addFirst(e);
return true;
}
/**
* Inserts the specified element at the end of this list.
*
* @param e the element to insert
* @return true (as specified by {@link Deque#offerLast})
* @since 1.6
*/
public boolean offerLast(E e) {
addLast(e);
return true;
}
/**
* Retrieves, but does not remove, the first element of this list,
* or returns null if this list is empty.
*
* @return the first element of this list, or null
* if this list is empty
* @since 1.6
*/
public E peekFirst() {
if (size==0)
return null;
return getFirst();
}
/**
* Retrieves, but does not remove, the last element of this list,
* or returns null if this list is empty.
*
* @return the last element of this list, or null
* if this list is empty
* @since 1.6
*/
public E peekLast() {
if (size==0)
return null;
return getLast();
}
/**
* Retrieves and removes the first element of this list,
* or returns null if this list is empty.
*
* @return the first element of this list, or null if
* this list is empty
* @since 1.6
*/
public E pollFirst() {
if (size==0)
return null;
return removeFirst();
}
/**
* Retrieves and removes the last element of this list,
* or returns null if this list is empty.
*
* @return the last element of this list, or null if
* this list is empty
* @since 1.6
*/
public E pollLast() {
if (size==0)
return null;
return removeLast();
}
/**
* Pushes an element onto the stack represented by this list. In other
* words, inserts the element at the front of this list.
*
* This method is equivalent to {@link #addFirst}.
*
* @param e the element to push
* @since 1.6
*/
public void push(E e) {
addFirst(e);
}
/**
* Pops an element from the stack represented by this list. In other
* words, removes and returns the first element of this list.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the element at the front of this list (which is the top
* of the stack represented by this list)
* @throws NoSuchElementException if this list is empty
* @since 1.6
*/
public E pop() {
return removeFirst();
}
/**
* Removes the first occurrence of the specified element in this
* list (when traversing the list from head to tail). If the list
* does not contain the element, it is unchanged.
*
* @param o element to be removed from this list, if present
* @return true if the list contained the specified element
* @since 1.6
*/
public boolean removeFirstOccurrence(Object o) {
return remove(o);
}
/**
* Removes the last occurrence of the specified element in this
* list (when traversing the list from head to tail). If the list
* does not contain the element, it is unchanged.
*
* @param o element to be removed from this list, if present
* @return true if the list contained the specified element
* @since 1.6
*/
public boolean removeLastOccurrence(Object o) {
if (o==null) {
for (Entry e = header.previous; e != header; e = e.previous) {
if (e.element==null) {
remove(e);
return true;
}
}
} else {
for (Entry e = header.previous; e != header; e = e.previous) {
if (o.equals(e.element)) {
remove(e);
return true;
}
}
}
return false;
}
/**
* Returns a list-iterator of the elements in this list (in proper
* sequence), starting at the specified position in the list.
* Obeys the general contract of List.listIterator(int).
*
* The list-iterator is fail-fast: if the list is structurally
* modified at any time after the Iterator is created, in any way except
* through the list-iterator's own remove or add
* methods, the list-iterator will throw a
* ConcurrentModificationException. Thus, in the face of
* concurrent modification, the iterator fails quickly and cleanly, rather
* than risking arbitrary, non-deterministic behavior at an undetermined
* time in the future.
*
* @param index index of the first element to be returned from the
* list-iterator (by a call to next)
* @return a ListIterator of the elements in this list (in proper
* sequence), starting at the specified position in the list
* @throws IndexOutOfBoundsException {@inheritDoc}
* @see List#listIterator(int)
*/
public ListIterator listIterator(int index) {
return new ListItr(index);
}
private class ListItr implements ListIterator {
private Entry lastReturned = header;
private Entry next;
private int nextIndex;
private int expectedModCount = modCount;
ListItr(int index) {
if (index < 0 || index > size)
throw new IndexOutOfBoundsException();
if (index < (size >> 1)) {
next = header.next;
for (nextIndex=0; nextIndexindex; nextIndex--)
next = next.previous;
}
}
public boolean hasNext() {
return nextIndex != size;
}
public E next() {
checkForComodification();
if (nextIndex == size)
throw new NoSuchElementException();
lastReturned = next;
next = next.next;
nextIndex++;
return lastReturned.element;
}
public boolean hasPrevious() {
return nextIndex != 0;
}
public E previous() {
if (nextIndex == 0)
throw new NoSuchElementException();
lastReturned = next = next.previous;
nextIndex--;
checkForComodification();
return lastReturned.element;
}
public int nextIndex() {
return nextIndex;
}
public int previousIndex() {
return nextIndex-1;
}
public void remove() {
checkForComodification();
Entry lastNext = lastReturned.next;
try {
LinkedList.this.remove(lastReturned);
} catch (NoSuchElementException e) {
throw new IllegalStateException();
}
if (next==lastReturned)
next = lastNext;
else
nextIndex--;
lastReturned = header;
expectedModCount++;
}
public void set(E e) {
if (lastReturned == header)
throw new IllegalStateException();
checkForComodification();
lastReturned.element = e;
}
public void add(E e) {
checkForComodification();
lastReturned = header;
addBefore(e, next);
nextIndex++;
expectedModCount++;
}
final void checkForComodification() {
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
}
}
private static class Entry {
E element;
Entry next;
Entry previous;
Entry(E element, Entry next, Entry previous) {
this.element = element;
this.next = next;
this.previous = previous;
}
}
private Entry addBefore(E e, Entry entry) {
Entry newEntry = new Entry(e, entry, entry.previous);
newEntry.previous.next = newEntry;
newEntry.next.previous = newEntry;
size++;
modCount++;
return newEntry;
}
private E remove(Entry e) {
if (e == header)
throw new NoSuchElementException();
E result = e.element;
e.previous.next = e.next;
e.next.previous = e.previous;
e.next = e.previous = null;
e.element = null;
size--;
modCount++;
return result;
}
/**
* @since 1.6
*/
public Iterator descendingIterator() {
return new DescendingIterator();
}
/** Adapter to provide descending iterators via ListItr.previous */
private class DescendingIterator implements Iterator {
final ListItr itr = new ListItr(size());
public boolean hasNext() {
return itr.hasPrevious();
}
public E next() {
return itr.previous();
}
public void remove() {
itr.remove();
}
}
/**
* Returns an array containing all of the elements in this list
* in proper sequence (from first to last element).
*
* The returned array will be "safe" in that no references to it are
* maintained by this list. (In other words, this method must allocate
* a new array). The caller is thus free to modify the returned array.
*
*
This method acts as bridge between array-based and collection-based
* APIs.
*
* @return an array containing all of the elements in this list
* in proper sequence
*/
public Object[] toArray() {
Object[] result = new Object[size];
int i = 0;
for (Entry e = header.next; e != header; e = e.next)
result[i++] = e.element;
return result;
}
private static final long serialVersionUID = 876323262645176354L;
}
/*
* Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* An iterator for lists that allows the programmer
* to traverse the list in either direction, modify
* the list during iteration, and obtain the iterator's
* current position in the list. A {@code ListIterator}
* has no current element; its cursor position always
* lies between the element that would be returned by a call
* to {@code previous()} and the element that would be
* returned by a call to {@code next()}.
* An iterator for a list of length {@code n} has {@code n+1} possible
* cursor positions, as illustrated by the carets ({@code ^}) below:
*
* Element(0) Element(1) Element(2) ... Element(n-1)
* cursor positions: ^ ^ ^ ^ ^
*
* Note that the {@link #remove} and {@link #set(Object)} methods are
* not defined in terms of the cursor position; they are defined to
* operate on the last element returned by a call to {@link #next} or
* {@link #previous()}.
*
* This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @see Collection
* @see List
* @see Iterator
* @see Enumeration
* @see List#listIterator()
* @since 1.2
*/
public interface ListIterator extends Iterator {
// Query Operations
/**
* Returns {@code true} if this list iterator has more elements when
* traversing the list in the forward direction. (In other words,
* returns {@code true} if {@link #next} would return an element rather
* than throwing an exception.)
*
* @return {@code true} if the list iterator has more elements when
* traversing the list in the forward direction
*/
boolean hasNext();
/**
* Returns the next element in the list and advances the cursor position.
* This method may be called repeatedly to iterate through the list,
* or intermixed with calls to {@link #previous} to go back and forth.
* (Note that alternating calls to {@code next} and {@code previous}
* will return the same element repeatedly.)
*
* @return the next element in the list
* @throws NoSuchElementException if the iteration has no next element
*/
E next();
/**
* Returns {@code true} if this list iterator has more elements when
* traversing the list in the reverse direction. (In other words,
* returns {@code true} if {@link #previous} would return an element
* rather than throwing an exception.)
*
* @return {@code true} if the list iterator has more elements when
* traversing the list in the reverse direction
*/
boolean hasPrevious();
/**
* Returns the previous element in the list and moves the cursor
* position backwards. This method may be called repeatedly to
* iterate through the list backwards, or intermixed with calls to
* {@link #next} to go back and forth. (Note that alternating calls
* to {@code next} and {@code previous} will return the same
* element repeatedly.)
*
* @return the previous element in the list
* @throws NoSuchElementException if the iteration has no previous
* element
*/
E previous();
/**
* Returns the index of the element that would be returned by a
* subsequent call to {@link #next}. (Returns list size if the list
* iterator is at the end of the list.)
*
* @return the index of the element that would be returned by a
* subsequent call to {@code next}, or list size if the list
* iterator is at the end of the list
*/
int nextIndex();
/**
* Returns the index of the element that would be returned by a
* subsequent call to {@link #previous}. (Returns -1 if the list
* iterator is at the beginning of the list.)
*
* @return the index of the element that would be returned by a
* subsequent call to {@code previous}, or -1 if the list
* iterator is at the beginning of the list
*/
int previousIndex();
// Modification Operations
/**
* Removes from the list the last element that was returned by {@link
* #next} or {@link #previous} (optional operation). This call can
* only be made once per call to {@code next} or {@code previous}.
* It can be made only if {@link #add} has not been
* called after the last call to {@code next} or {@code previous}.
*
* @throws UnsupportedOperationException if the {@code remove}
* operation is not supported by this list iterator
* @throws IllegalStateException if neither {@code next} nor
* {@code previous} have been called, or {@code remove} or
* {@code add} have been called after the last call to
* {@code next} or {@code previous}
*/
void remove();
/**
* Replaces the last element returned by {@link #next} or
* {@link #previous} with the specified element (optional operation).
* This call can be made only if neither {@link #remove} nor {@link
* #add} have been called after the last call to {@code next} or
* {@code previous}.
*
* @param e the element with which to replace the last element returned by
* {@code next} or {@code previous}
* @throws UnsupportedOperationException if the {@code set} operation
* is not supported by this list iterator
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws IllegalArgumentException if some aspect of the specified
* element prevents it from being added to this list
* @throws IllegalStateException if neither {@code next} nor
* {@code previous} have been called, or {@code remove} or
* {@code add} have been called after the last call to
* {@code next} or {@code previous}
*/
void set(E e);
/**
* Inserts the specified element into the list (optional operation).
* The element is inserted immediately before the next element that
* would be returned by {@link #next}, if any, and after the next
* element that would be returned by {@link #previous}, if any. (If the
* list contains no elements, the new element becomes the sole element
* on the list.) The new element is inserted before the implicit
* cursor: a subsequent call to {@code next} would be unaffected, and a
* subsequent call to {@code previous} would return the new element.
* (This call increases by one the value that would be returned by a
* call to {@code nextIndex} or {@code previousIndex}.)
*
* @param e the element to insert
* @throws UnsupportedOperationException if the {@code add} method is
* not supported by this list iterator
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws IllegalArgumentException if some aspect of this element
* prevents it from being added to this list
*/
void add(E e);
}
/*
* Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* An ordered collection (also known as a sequence). The user of this
* interface has precise control over where in the list each element is
* inserted. The user can access elements by their integer index (position in
* the list), and search for elements in the list.
*
* Unlike sets, lists typically allow duplicate elements. More formally,
* lists typically allow pairs of elements e1 and e2
* such that e1.equals(e2), and they typically allow multiple
* null elements if they allow null elements at all. It is not inconceivable
* that someone might wish to implement a list that prohibits duplicates, by
* throwing runtime exceptions when the user attempts to insert them, but we
* expect this usage to be rare.
*
* The List interface places additional stipulations, beyond those
* specified in the Collection interface, on the contracts of the
* iterator, add, remove, equals, and
* hashCode methods. Declarations for other inherited methods are
* also included here for convenience.
*
* The List interface provides four methods for positional (indexed)
* access to list elements. Lists (like Java arrays) are zero based. Note
* that these operations may execute in time proportional to the index value
* for some implementations (the LinkedList class, for
* example). Thus, iterating over the elements in a list is typically
* preferable to indexing through it if the caller does not know the
* implementation.
*
* The List interface provides a special iterator, called a
* ListIterator, that allows element insertion and replacement, and
* bidirectional access in addition to the normal operations that the
* Iterator interface provides. A method is provided to obtain a
* list iterator that starts at a specified position in the list.
*
* The List interface provides two methods to search for a specified
* object. From a performance standpoint, these methods should be used with
* caution. In many implementations they will perform costly linear
* searches.
*
* The List interface provides two methods to efficiently insert and
* remove multiple elements at an arbitrary point in the list.
*
* Note: While it is permissible for lists to contain themselves as elements,
* extreme caution is advised: the equals and hashCode
* methods are no longer well defined on such a list.
*
*
Some list implementations have restrictions on the elements that
* they may contain. For example, some implementations prohibit null elements,
* and some have restrictions on the types of their elements. Attempting to
* add an ineligible element throws an unchecked exception, typically
* NullPointerException or ClassCastException. Attempting
* to query the presence of an ineligible element may throw an exception,
* or it may simply return false; some implementations will exhibit the former
* behavior and some will exhibit the latter. More generally, attempting an
* operation on an ineligible element whose completion would not result in
* the insertion of an ineligible element into the list may throw an
* exception or it may succeed, at the option of the implementation.
* Such exceptions are marked as "optional" in the specification for this
* interface.
*
*
This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Collection
* @see Set
* @see ArrayList
* @see LinkedList
* @see Vector
* @see Arrays#asList(Object[])
* @see Collections#nCopies(int, Object)
* @see Collections#EMPTY_LIST
* @see AbstractList
* @see AbstractSequentialList
* @since 1.2
*/
public interface List extends Collection {
// Query Operations
/**
* Returns the number of elements in this list. If this list contains
* more than Integer.MAX_VALUE elements, returns
* Integer.MAX_VALUE.
*
* @return the number of elements in this list
*/
int size();
/**
* Returns true if this list contains no elements.
*
* @return true if this list contains no elements
*/
boolean isEmpty();
/**
* Returns true if this list contains the specified element.
* More formally, returns true if and only if this list contains
* at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this list is to be tested
* @return true if this list contains the specified element
* @throws ClassCastException if the type of the specified element
* is incompatible with this list (optional)
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements (optional)
*/
boolean contains(Object o);
/**
* Returns an iterator over the elements in this list in proper sequence.
*
* @return an iterator over the elements in this list in proper sequence
*/
Iterator iterator();
// Modification Operations
/**
* Appends the specified element to the end of this list (optional
* operation).
*
* Lists that support this operation may place limitations on what
* elements may be added to this list. In particular, some
* lists will refuse to add null elements, and others will impose
* restrictions on the type of elements that may be added. List
* classes should clearly specify in their documentation any restrictions
* on what elements may be added.
*
* @param e element to be appended to this list
* @return true (as specified by {@link Collection#add})
* @throws UnsupportedOperationException if the add operation
* is not supported by this list
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this list
*/
boolean add(E e);
/**
* Removes the first occurrence of the specified element from this list,
* if it is present (optional operation). If this list does not contain
* the element, it is unchanged. More formally, removes the element with
* the lowest index i such that
* (o==null ? get(i)==null : o.equals(get(i)))
* (if such an element exists). Returns true if this list
* contained the specified element (or equivalently, if this list changed
* as a result of the call).
*
* @param o element to be removed from this list, if present
* @return true if this list contained the specified element
* @throws ClassCastException if the type of the specified element
* is incompatible with this list (optional)
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements (optional)
* @throws UnsupportedOperationException if the remove operation
* is not supported by this list
*/
boolean remove(Object o);
// Bulk Modification Operations
/**
* Returns true if this list contains all of the elements of the
* specified collection.
*
* @param c collection to be checked for containment in this list
* @return true if this list contains all of the elements of the
* specified collection
* @throws ClassCastException if the types of one or more elements
* in the specified collection are incompatible with this
* list (optional)
* @throws NullPointerException if the specified collection contains one
* or more null elements and this list does not permit null
* elements (optional), or if the specified collection is null
* @see #contains(Object)
*/
boolean containsAll(Collection c);
/**
* Appends all of the elements in the specified collection to the end of
* this list, in the order that they are returned by the specified
* collection's iterator (optional operation). The behavior of this
* operation is undefined if the specified collection is modified while
* the operation is in progress. (Note that this will occur if the
* specified collection is this list, and it's nonempty.)
*
* @param c collection containing elements to be added to this list
* @return true if this list changed as a result of the call
* @throws UnsupportedOperationException if the addAll operation
* is not supported by this list
* @throws ClassCastException if the class of an element of the specified
* collection prevents it from being added to this list
* @throws NullPointerException if the specified collection contains one
* or more null elements and this list does not permit null
* elements, or if the specified collection is null
* @throws IllegalArgumentException if some property of an element of the
* specified collection prevents it from being added to this list
* @see #add(Object)
*/
boolean addAll(Collection c);
/**
* Inserts all of the elements in the specified collection into this
* list at the specified position (optional operation). Shifts the
* element currently at that position (if any) and any subsequent
* elements to the right (increases their indices). The new elements
* will appear in this list in the order that they are returned by the
* specified collection's iterator. The behavior of this operation is
* undefined if the specified collection is modified while the
* operation is in progress. (Note that this will occur if the specified
* collection is this list, and it's nonempty.)
*
* @param index index at which to insert the first element from the
* specified collection
* @param c collection containing elements to be added to this list
* @return true if this list changed as a result of the call
* @throws UnsupportedOperationException if the addAll operation
* is not supported by this list
* @throws ClassCastException if the class of an element of the specified
* collection prevents it from being added to this list
* @throws NullPointerException if the specified collection contains one
* or more null elements and this list does not permit null
* elements, or if the specified collection is null
* @throws IllegalArgumentException if some property of an element of the
* specified collection prevents it from being added to this list
* @throws IndexOutOfBoundsException if the index is out of range
* (index < 0 || index > size())
*/
boolean addAll(int index, Collection c);
/**
* Removes from this list all of its elements that are contained in the
* specified collection (optional operation).
*
* @param c collection containing elements to be removed from this list
* @return true if this list changed as a result of the call
* @throws UnsupportedOperationException if the removeAll operation
* is not supported by this list
* @throws ClassCastException if the class of an element of this list
* is incompatible with the specified collection (optional)
* @throws NullPointerException if this list contains a null element and the
* specified collection does not permit null elements (optional),
* or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean removeAll(Collection c);
/**
* Retains only the elements in this list that are contained in the
* specified collection (optional operation). In other words, removes
* from this list all of its elements that are not contained in the
* specified collection.
*
* @param c collection containing elements to be retained in this list
* @return true if this list changed as a result of the call
* @throws UnsupportedOperationException if the retainAll operation
* is not supported by this list
* @throws ClassCastException if the class of an element of this list
* is incompatible with the specified collection (optional)
* @throws NullPointerException if this list contains a null element and the
* specified collection does not permit null elements (optional),
* or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean retainAll(Collection c);
/**
* Removes all of the elements from this list (optional operation).
* The list will be empty after this call returns.
*
* @throws UnsupportedOperationException if the clear operation
* is not supported by this list
*/
void clear();
// Comparison and hashing
/**
* Compares the specified object with this list for equality. Returns
* true if and only if the specified object is also a list, both
* lists have the same size, and all corresponding pairs of elements in
* the two lists are equal. (Two elements e1 and
* e2 are equal if (e1==null ? e2==null :
* e1.equals(e2)).) In other words, two lists are defined to be
* equal if they contain the same elements in the same order. This
* definition ensures that the equals method works properly across
* different implementations of the List interface.
*
* @param o the object to be compared for equality with this list
* @return true if the specified object is equal to this list
*/
boolean equals(Object o);
/**
* Returns the hash code value for this list. The hash code of a list
* is defined to be the result of the following calculation:
*
* int hashCode = 1;
* for (E e : list)
* hashCode = 31*hashCode + (e==null ? 0 : e.hashCode());
*
* This ensures that list1.equals(list2) implies that
* list1.hashCode()==list2.hashCode() for any two lists,
* list1 and list2, as required by the general
* contract of {@link Object#hashCode}.
*
* @return the hash code value for this list
* @see Object#equals(Object)
* @see #equals(Object)
*/
int hashCode();
// Positional Access Operations
/**
* Returns the element at the specified position in this list.
*
* @param index index of the element to return
* @return the element at the specified position in this list
* @throws IndexOutOfBoundsException if the index is out of range
* (index < 0 || index >= size())
*/
E get(int index);
/**
* Replaces the element at the specified position in this list with the
* specified element (optional operation).
*
* @param index index of the element to replace
* @param element element to be stored at the specified position
* @return the element previously at the specified position
* @throws UnsupportedOperationException if the set operation
* is not supported by this list
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws NullPointerException if the specified element is null and
* this list does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this list
* @throws IndexOutOfBoundsException if the index is out of range
* (index < 0 || index >= size())
*/
E set(int index, E element);
/**
* Inserts the specified element at the specified position in this list
* (optional operation). Shifts the element currently at that position
* (if any) and any subsequent elements to the right (adds one to their
* indices).
*
* @param index index at which the specified element is to be inserted
* @param element element to be inserted
* @throws UnsupportedOperationException if the add operation
* is not supported by this list
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws NullPointerException if the specified element is null and
* this list does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this list
* @throws IndexOutOfBoundsException if the index is out of range
* (index < 0 || index > size())
*/
void add(int index, E element);
/**
* Removes the element at the specified position in this list (optional
* operation). Shifts any subsequent elements to the left (subtracts one
* from their indices). Returns the element that was removed from the
* list.
*
* @param index the index of the element to be removed
* @return the element previously at the specified position
* @throws UnsupportedOperationException if the remove operation
* is not supported by this list
* @throws IndexOutOfBoundsException if the index is out of range
* (index < 0 || index >= size())
*/
E remove(int index);
// Search Operations
/**
* Returns the index of the first occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the lowest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the first occurrence of the specified element in
* this list, or -1 if this list does not contain the element
* @throws ClassCastException if the type of the specified element
* is incompatible with this list (optional)
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements (optional)
*/
int indexOf(Object o);
/**
* Returns the index of the last occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the highest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the last occurrence of the specified element in
* this list, or -1 if this list does not contain the element
* @throws ClassCastException if the type of the specified element
* is incompatible with this list (optional)
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements (optional)
*/
int lastIndexOf(Object o);
// List Iterators
/**
* Returns a list iterator over the elements in this list (in proper
* sequence).
*
* @return a list iterator over the elements in this list (in proper
* sequence)
*/
ListIterator listIterator();
/**
* Returns a list iterator over the elements in this list (in proper
* sequence), starting at the specified position in the list.
* The specified index indicates the first element that would be
* returned by an initial call to {@link ListIterator#next next}.
* An initial call to {@link ListIterator#previous previous} would
* return the element with the specified index minus one.
*
* @param index index of the first element to be returned from the
* list iterator (by a call to {@link ListIterator#next next})
* @return a list iterator over the elements in this list (in proper
* sequence), starting at the specified position in the list
* @throws IndexOutOfBoundsException if the index is out of range
* ({@code index < 0 || index > size()})
*/
ListIterator listIterator(int index);
// View
/**
* Returns a view of the portion of this list between the specified
* fromIndex, inclusive, and toIndex, exclusive. (If
* fromIndex and toIndex are equal, the returned list is
* empty.) The returned list is backed by this list, so non-structural
* changes in the returned list are reflected in this list, and vice-versa.
* The returned list supports all of the optional list operations supported
* by this list.
*
* This method eliminates the need for explicit range operations (of
* the sort that commonly exist for arrays). Any operation that expects
* a list can be used as a range operation by passing a subList view
* instead of a whole list. For example, the following idiom
* removes a range of elements from a list:
*
* list.subList(from, to).clear();
*
* Similar idioms may be constructed for indexOf and
* lastIndexOf, and all of the algorithms in the
* Collections class can be applied to a subList.
*
* The semantics of the list returned by this method become undefined if
* the backing list (i.e., this list) is structurally modified in
* any way other than via the returned list. (Structural modifications are
* those that change the size of this list, or otherwise perturb it in such
* a fashion that iterations in progress may yield incorrect results.)
*
* @param fromIndex low endpoint (inclusive) of the subList
* @param toIndex high endpoint (exclusive) of the subList
* @return a view of the specified range within this list
* @throws IndexOutOfBoundsException for an illegal endpoint index value
* (fromIndex < 0 || toIndex > size ||
* fromIndex > toIndex)
*/
List subList(int fromIndex, int toIndex);
}
/*
* Copyright 1994-1998 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Thrown by the nextElement method of an
* Enumeration to indicate that there are no more
* elements in the enumeration.
*
* @author unascribed
* @see java.util.Enumeration
* @see java.util.Enumeration#nextElement()
* @since JDK1.0
*/
public
class NoSuchElementException extends RuntimeException {
/**
* Constructs a NoSuchElementException with null
* as its error message string.
*/
public NoSuchElementException() {
super();
}
/**
* Constructs a NoSuchElementException, saving a reference
* to the error message string s for later retrieval by the
* getMessage method.
*
* @param s the detail message.
*/
public NoSuchElementException(String s) {
super(s);
}
}
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/licenses/publicdomain
*/
package javaUtilEx;
/**
* A collection designed for holding elements prior to processing.
* Besides basic {@link java.util.Collection Collection} operations,
* queues provide additional insertion, extraction, and inspection
* operations. Each of these methods exists in two forms: one throws
* an exception if the operation fails, the other returns a special
* value (either null or false, depending on the
* operation). The latter form of the insert operation is designed
* specifically for use with capacity-restricted Queue
* implementations; in most implementations, insert operations cannot
* fail.
*
*
*
*
* |
* Throws exception |
* Returns special value |
*
*
* | Insert |
* {@link #add add(e)} |
* {@link #offer offer(e)} |
*
*
* | Remove |
* {@link #remove remove()} |
* {@link #poll poll()} |
*
*
* | Examine |
* {@link #element element()} |
* {@link #peek peek()} |
*
*
*
* Queues typically, but do not necessarily, order elements in a
* FIFO (first-in-first-out) manner. Among the exceptions are
* priority queues, which order elements according to a supplied
* comparator, or the elements' natural ordering, and LIFO queues (or
* stacks) which order the elements LIFO (last-in-first-out).
* Whatever the ordering used, the head of the queue is that
* element which would be removed by a call to {@link #remove() } or
* {@link #poll()}. In a FIFO queue, all new elements are inserted at
* the tail of the queue. Other kinds of queues may use
* different placement rules. Every Queue implementation
* must specify its ordering properties.
*
*
The {@link #offer offer} method inserts an element if possible,
* otherwise returning false. This differs from the {@link
* java.util.Collection#add Collection.add} method, which can fail to
* add an element only by throwing an unchecked exception. The
* offer method is designed for use when failure is a normal,
* rather than exceptional occurrence, for example, in fixed-capacity
* (or "bounded") queues.
*
*
The {@link #remove()} and {@link #poll()} methods remove and
* return the head of the queue.
* Exactly which element is removed from the queue is a
* function of the queue's ordering policy, which differs from
* implementation to implementation. The remove() and
* poll() methods differ only in their behavior when the
* queue is empty: the remove() method throws an exception,
* while the poll() method returns null.
*
*
The {@link #element()} and {@link #peek()} methods return, but do
* not remove, the head of the queue.
*
*
The Queue interface does not define the blocking queue
* methods, which are common in concurrent programming. These methods,
* which wait for elements to appear or for space to become available, are
* defined in the {@link java.util.concurrent.BlockingQueue} interface, which
* extends this interface.
*
*
Queue implementations generally do not allow insertion
* of null elements, although some implementations, such as
* {@link LinkedList}, do not prohibit insertion of null.
* Even in the implementations that permit it, null should
* not be inserted into a Queue, as null is also
* used as a special return value by the poll method to
* indicate that the queue contains no elements.
*
*
Queue implementations generally do not define
* element-based versions of methods equals and
* hashCode but instead inherit the identity based versions
* from class Object, because element-based equality is not
* always well-defined for queues with the same elements but different
* ordering properties.
*
*
*
This interface is a member of the
*
* Java Collections Framework.
*
* @see java.util.Collection
* @see LinkedList
* @see PriorityQueue
* @see java.util.concurrent.LinkedBlockingQueue
* @see java.util.concurrent.BlockingQueue
* @see java.util.concurrent.ArrayBlockingQueue
* @see java.util.concurrent.LinkedBlockingQueue
* @see java.util.concurrent.PriorityBlockingQueue
* @since 1.5
* @author Doug Lea
* @param the type of elements held in this collection
*/
public interface Queue extends Collection {
/**
* Inserts the specified element into this queue if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and throwing an IllegalStateException
* if no space is currently available.
*
* @param e the element to add
* @return true (as specified by {@link Collection#add})
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
*/
boolean add(E e);
/**
* Inserts the specified element into this queue if it is possible to do
* so immediately without violating capacity restrictions.
* When using a capacity-restricted queue, this method is generally
* preferable to {@link #add}, which can fail to insert an element only
* by throwing an exception.
*
* @param e the element to add
* @return true if the element was added to this queue, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this queue
* @throws NullPointerException if the specified element is null and
* this queue does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this queue
*/
boolean offer(E e);
/**
* Retrieves and removes the head of this queue. This method differs
* from {@link #poll poll} only in that it throws an exception if this
* queue is empty.
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
*/
E remove();
/**
* Retrieves and removes the head of this queue,
* or returns null if this queue is empty.
*
* @return the head of this queue, or null if this queue is empty
*/
E poll();
/**
* Retrieves, but does not remove, the head of this queue. This method
* differs from {@link #peek peek} only in that it throws an exception
* if this queue is empty.
*
* @return the head of this queue
* @throws NoSuchElementException if this queue is empty
*/
E element();
/**
* Retrieves, but does not remove, the head of this queue,
* or returns null if this queue is empty.
*
* @return the head of this queue, or null if this queue is empty
*/
E peek();
}
/*
* Copyright 2000-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Marker interface used by List implementations to indicate that
* they support fast (generally constant time) random access. The primary
* purpose of this interface is to allow generic algorithms to alter their
* behavior to provide good performance when applied to either random or
* sequential access lists.
*
* The best algorithms for manipulating random access lists (such as
* ArrayList) can produce quadratic behavior when applied to
* sequential access lists (such as LinkedList). Generic list
* algorithms are encouraged to check whether the given list is an
* instanceof this interface before applying an algorithm that would
* provide poor performance if it were applied to a sequential access list,
* and to alter their behavior if necessary to guarantee acceptable
* performance.
*
*
It is recognized that the distinction between random and sequential
* access is often fuzzy. For example, some List implementations
* provide asymptotically linear access times if they get huge, but constant
* access times in practice. Such a List implementation
* should generally implement this interface. As a rule of thumb, a
* List implementation should implement this interface if,
* for typical instances of the class, this loop:
*
* for (int i=0, n=list.size(); i < n; i++)
* list.get(i);
*
* runs faster than this loop:
*
* for (Iterator i=list.iterator(); i.hasNext(); )
* i.next();
*
*
* This interface is a member of the
*
* Java Collections Framework.
*
* @since 1.4
*/
public interface RandomAccess {
}
package javaUtilEx;
public class Random {
static String[] args;
static int index = 0;
public static int random() {
String string = args[index];
index++;
return string.length();
}
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Thrown to indicate that the requested operation is not supported.
*
* This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @since 1.2
*/
public class UnsupportedOperationException extends RuntimeException {
/**
* Constructs an UnsupportedOperationException with no detail message.
*/
public UnsupportedOperationException() {
}
/**
* Constructs an UnsupportedOperationException with the specified
* detail message.
*
* @param message the detail message
*/
public UnsupportedOperationException(String message) {
super(message);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
*
Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public UnsupportedOperationException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of (cause==null ? null : cause.toString()) (which
* typically contains the class and detail message of cause).
* This constructor is useful for exceptions that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public UnsupportedOperationException(Throwable cause) {
super(cause);
}
static final long serialVersionUID = -1242599979055084673L;
}
----------------------------------------
(1) BareJBCToJBCProof (EQUIVALENT)
initialized classpath
----------------------------------------
(2)
Obligation:
need to prove termination of the following program:
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the Collection
* interface, to minimize the effort required to implement this interface.
*
* To implement an unmodifiable collection, the programmer needs only to
* extend this class and provide implementations for the iterator and
* size methods. (The iterator returned by the iterator
* method must implement hasNext and next.)
*
* To implement a modifiable collection, the programmer must additionally
* override this class's add method (which otherwise throws an
* UnsupportedOperationException), and the iterator returned by the
* iterator method must additionally implement its remove
* method.
*
* The programmer should generally provide a void (no argument) and
* Collection constructor, as per the recommendation in the
* Collection interface specification.
*
* The documentation for each non-abstract method in this class describes its
* implementation in detail. Each of these methods may be overridden if
* the collection being implemented admits a more efficient implementation.
*
* This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Collection
* @since 1.2
*/
public abstract class AbstractCollection implements Collection {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractCollection() {
}
// Query Operations
/**
* Returns an iterator over the elements contained in this collection.
*
* @return an iterator over the elements contained in this collection
*/
public abstract Iterator iterator();
public abstract int size();
/**
* {@inheritDoc}
*
* This implementation returns size() == 0.
*/
public boolean isEmpty() {
return size() == 0;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the elements in the collection,
* checking each element in turn for equality with the specified element.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public boolean contains(Object o) {
Iterator e = iterator();
if (o==null) {
while (e.hasNext())
if (e.next()==null)
return true;
} else {
while (e.hasNext())
if (o.equals(e.next()))
return true;
}
return false;
}
// Modification Operations
/**
* {@inheritDoc}
*
* This implementation always throws an
* UnsupportedOperationException.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IllegalStateException {@inheritDoc}
*/
public boolean add(E e) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the collection looking for the
* specified element. If it finds the element, it removes the element
* from the collection using the iterator's remove method.
*
*
Note that this implementation throws an
* UnsupportedOperationException if the iterator returned by this
* collection's iterator method does not implement the remove
* method and this collection contains the specified object.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public boolean remove(Object o) {
Iterator e = iterator();
if (o==null) {
while (e.hasNext()) {
if (e.next()==null) {
e.remove();
return true;
}
}
} else {
while (e.hasNext()) {
if (o.equals(e.next())) {
e.remove();
return true;
}
}
}
return false;
}
// Bulk Operations
/**
* {@inheritDoc}
*
* This implementation iterates over the specified collection,
* checking each element returned by the iterator in turn to see
* if it's contained in this collection. If all elements are so
* contained true is returned, otherwise false.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @see #contains(Object)
*/
public boolean containsAll(Collection c) {
Iterator e = c.iterator();
while (e.hasNext())
if (!contains(e.next()))
return false;
return true;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over the specified collection, and adds
* each object returned by the iterator to this collection, in turn.
*
*
Note that this implementation will throw an
* UnsupportedOperationException unless add is
* overridden (assuming the specified collection is non-empty).
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IllegalStateException {@inheritDoc}
*
* @see #add(Object)
*/
public boolean addAll(Collection c) {
boolean modified = false;
Iterator e = c.iterator();
while (e.hasNext()) {
if (add(e.next()))
modified = true;
}
return modified;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over this collection, checking each
* element returned by the iterator in turn to see if it's contained
* in the specified collection. If it's so contained, it's removed from
* this collection with the iterator's remove method.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by the
* iterator method does not implement the remove method
* and this collection contains one or more elements in common with the
* specified collection.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*
* @see #remove(Object)
* @see #contains(Object)
*/
public boolean removeAll(Collection c) {
boolean modified = false;
Iterator e = iterator();
while (e.hasNext()) {
if (c.contains(e.next())) {
e.remove();
modified = true;
}
}
return modified;
}
/**
* {@inheritDoc}
*
*
This implementation iterates over this collection, checking each
* element returned by the iterator in turn to see if it's contained
* in the specified collection. If it's not so contained, it's removed
* from this collection with the iterator's remove method.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by the
* iterator method does not implement the remove method
* and this collection contains one or more elements not present in the
* specified collection.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*
* @see #remove(Object)
* @see #contains(Object)
*/
public boolean retainAll(Collection c) {
boolean modified = false;
Iterator e = iterator();
while (e.hasNext()) {
if (!c.contains(e.next())) {
e.remove();
modified = true;
}
}
return modified;
}
/**
* {@inheritDoc}
*
* This implementation iterates over this collection, removing each
* element using the Iterator.remove operation. Most
* implementations will probably choose to override this method for
* efficiency.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the iterator returned by this
* collection's iterator method does not implement the
* remove method and this collection is non-empty.
*
* @throws UnsupportedOperationException {@inheritDoc}
*/
public void clear() {
Iterator e = iterator();
while (e.hasNext()) {
e.next();
e.remove();
}
}
// String conversion
/**
* Returns a string representation of this collection. The string
* representation consists of a list of the collection's elements in the
* order they are returned by its iterator, enclosed in square brackets
* ("[]"). Adjacent elements are separated by the characters
* ", " (comma and space). Elements are converted to strings as
* by {@link String#valueOf(Object)}.
*
* @return a string representation of this collection
*/
public String toString() {
Iterator i = iterator();
if (! i.hasNext())
return "[]";
String sb = "";
sb = sb + "[";
for (;;) {
E e = i.next();
sb = sb + (e == this ? "(this Collection)" : e);
if (! i.hasNext()) {
sb = sb + "]";
return sb;
}
sb = sb + ", ";
}
}
}
/*
* Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the {@link List}
* interface to minimize the effort required to implement this interface
* backed by a "random access" data store (such as an array). For sequential
* access data (such as a linked list), {@link AbstractSequentialList} should
* be used in preference to this class.
*
* To implement an unmodifiable list, the programmer needs only to extend
* this class and provide implementations for the {@link #get(int)} and
* {@link List#size() size()} methods.
*
*
To implement a modifiable list, the programmer must additionally
* override the {@link #set(int, Object) set(int, E)} method (which otherwise
* throws an {@code UnsupportedOperationException}). If the list is
* variable-size the programmer must additionally override the
* {@link #add(int, Object) add(int, E)} and {@link #remove(int)} methods.
*
*
The programmer should generally provide a void (no argument) and collection
* constructor, as per the recommendation in the {@link Collection} interface
* specification.
*
*
Unlike the other abstract collection implementations, the programmer does
* not have to provide an iterator implementation; the iterator and
* list iterator are implemented by this class, on top of the "random access"
* methods:
* {@link #get(int)},
* {@link #set(int, Object) set(int, E)},
* {@link #add(int, Object) add(int, E)} and
* {@link #remove(int)}.
*
*
The documentation for each non-abstract method in this class describes its
* implementation in detail. Each of these methods may be overridden if the
* collection being implemented admits a more efficient implementation.
*
*
This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @since 1.2
*/
public abstract class AbstractList extends AbstractCollection implements List {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractList() {
}
/**
* Appends the specified element to the end of this list (optional
* operation).
*
* Lists that support this operation may place limitations on what
* elements may be added to this list. In particular, some
* lists will refuse to add null elements, and others will impose
* restrictions on the type of elements that may be added. List
* classes should clearly specify in their documentation any restrictions
* on what elements may be added.
*
*
This implementation calls {@code add(size(), e)}.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless
* {@link #add(int, Object) add(int, E)} is overridden.
*
* @param e element to be appended to this list
* @return {@code true} (as specified by {@link Collection#add})
* @throws UnsupportedOperationException if the {@code add} operation
* is not supported by this list
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this list
* @throws NullPointerException if the specified element is null and this
* list does not permit null elements
* @throws IllegalArgumentException if some property of this element
* prevents it from being added to this list
*/
public boolean add(E e) {
add(size(), e);
return true;
}
/**
* {@inheritDoc}
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
abstract public E get(int index);
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc}
*
*
This implementation always throws an
* {@code UnsupportedOperationException}.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
throw new UnsupportedOperationException();
}
// Search Operations
/**
* {@inheritDoc}
*
*
This implementation first gets a list iterator (with
* {@code listIterator()}). Then, it iterates over the list until the
* specified element is found or the end of the list is reached.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public int indexOf(Object o) {
ListIterator e = listIterator();
if (o==null) {
while (e.hasNext())
if (e.next()==null)
return e.previousIndex();
} else {
while (e.hasNext())
if (o.equals(e.next()))
return e.previousIndex();
}
return -1;
}
/**
* {@inheritDoc}
*
* This implementation first gets a list iterator that points to the end
* of the list (with {@code listIterator(size())}). Then, it iterates
* backwards over the list until the specified element is found, or the
* beginning of the list is reached.
*
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public int lastIndexOf(Object o) {
ListIterator e = listIterator(size());
if (o==null) {
while (e.hasPrevious())
if (e.previous()==null)
return e.nextIndex();
} else {
while (e.hasPrevious())
if (o.equals(e.previous()))
return e.nextIndex();
}
return -1;
}
// Bulk Operations
/**
* Removes all of the elements from this list (optional operation).
* The list will be empty after this call returns.
*
* This implementation calls {@code removeRange(0, size())}.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless {@code remove(int
* index)} or {@code removeRange(int fromIndex, int toIndex)} is
* overridden.
*
* @throws UnsupportedOperationException if the {@code clear} operation
* is not supported by this list
*/
public void clear() {
removeRange(0, size());
}
/**
* {@inheritDoc}
*
*
This implementation gets an iterator over the specified collection
* and iterates over it, inserting the elements obtained from the
* iterator into this list at the appropriate position, one at a time,
* using {@code add(int, E)}.
* Many implementations will override this method for efficiency.
*
*
Note that this implementation throws an
* {@code UnsupportedOperationException} unless
* {@link #add(int, Object) add(int, E)} is overridden.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public boolean addAll(int index, Collection c) {
rangeCheckForAdd(index);
boolean modified = false;
Iterator e = c.iterator();
while (e.hasNext()) {
add(index++, e.next());
modified = true;
}
return modified;
}
// Iterators
/**
* Returns an iterator over the elements in this list in proper sequence.
*
*
This implementation returns a straightforward implementation of the
* iterator interface, relying on the backing list's {@code size()},
* {@code get(int)}, and {@code remove(int)} methods.
*
*
Note that the iterator returned by this method will throw an
* {@link UnsupportedOperationException} in response to its
* {@code remove} method unless the list's {@code remove(int)} method is
* overridden.
*
*
This implementation can be made to throw runtime exceptions in the
* face of concurrent modification, as described in the specification
* for the (protected) {@link #modCount} field.
*
* @return an iterator over the elements in this list in proper sequence
*/
public Iterator iterator() {
return new Itr();
}
/**
* {@inheritDoc}
*
* This implementation returns {@code listIterator(0)}.
*
* @see #listIterator(int)
*/
public ListIterator listIterator() {
return listIterator(0);
}
/**
* {@inheritDoc}
*
* This implementation returns a straightforward implementation of the
* {@code ListIterator} interface that extends the implementation of the
* {@code Iterator} interface returned by the {@code iterator()} method.
* The {@code ListIterator} implementation relies on the backing list's
* {@code get(int)}, {@code set(int, E)}, {@code add(int, E)}
* and {@code remove(int)} methods.
*
*
Note that the list iterator returned by this implementation will
* throw an {@link UnsupportedOperationException} in response to its
* {@code remove}, {@code set} and {@code add} methods unless the
* list's {@code remove(int)}, {@code set(int, E)}, and
* {@code add(int, E)} methods are overridden.
*
*
This implementation can be made to throw runtime exceptions in the
* face of concurrent modification, as described in the specification for
* the (protected) {@link #modCount} field.
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public ListIterator listIterator(final int index) {
rangeCheckForAdd(index);
return new ListItr(index);
}
private class Itr implements Iterator {
/**
* Index of element to be returned by subsequent call to next.
*/
int cursor = 0;
/**
* Index of element returned by most recent call to next or
* previous. Reset to -1 if this element is deleted by a call
* to remove.
*/
int lastRet = -1;
/**
* The modCount value that the iterator believes that the backing
* List should have. If this expectation is violated, the iterator
* has detected concurrent modification.
*/
int expectedModCount = modCount;
public boolean hasNext() {
return cursor != size();
}
public E next() {
checkForComodification();
try {
int i = cursor;
E next = get(i);
lastRet = i;
cursor = i + 1;
return next;
} catch (IndexOutOfBoundsException e) {
checkForComodification();
throw new NoSuchElementException();
}
}
public void remove() {
if (lastRet < 0)
throw new IllegalStateException();
checkForComodification();
try {
AbstractList.this.remove(lastRet);
if (lastRet < cursor)
cursor--;
lastRet = -1;
expectedModCount = modCount;
} catch (IndexOutOfBoundsException e) {
throw new ConcurrentModificationException();
}
}
final void checkForComodification() {
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
}
}
private class ListItr extends Itr implements ListIterator {
ListItr(int index) {
cursor = index;
}
public boolean hasPrevious() {
return cursor != 0;
}
public E previous() {
checkForComodification();
try {
int i = cursor - 1;
E previous = get(i);
lastRet = cursor = i;
return previous;
} catch (IndexOutOfBoundsException e) {
checkForComodification();
throw new NoSuchElementException();
}
}
public int nextIndex() {
return cursor;
}
public int previousIndex() {
return cursor-1;
}
public void set(E e) {
if (lastRet < 0)
throw new IllegalStateException();
checkForComodification();
try {
AbstractList.this.set(lastRet, e);
expectedModCount = modCount;
} catch (IndexOutOfBoundsException ex) {
throw new ConcurrentModificationException();
}
}
public void add(E e) {
checkForComodification();
try {
int i = cursor;
AbstractList.this.add(i, e);
lastRet = -1;
cursor = i + 1;
expectedModCount = modCount;
} catch (IndexOutOfBoundsException ex) {
throw new ConcurrentModificationException();
}
}
}
/**
* {@inheritDoc}
*
* This implementation returns a list that subclasses
* {@code AbstractList}. The subclass stores, in private fields, the
* offset of the subList within the backing list, the size of the subList
* (which can change over its lifetime), and the expected
* {@code modCount} value of the backing list. There are two variants
* of the subclass, one of which implements {@code RandomAccess}.
* If this list implements {@code RandomAccess} the returned list will
* be an instance of the subclass that implements {@code RandomAccess}.
*
*
The subclass's {@code set(int, E)}, {@code get(int)},
* {@code add(int, E)}, {@code remove(int)}, {@code addAll(int,
* Collection)} and {@code removeRange(int, int)} methods all
* delegate to the corresponding methods on the backing abstract list,
* after bounds-checking the index and adjusting for the offset. The
* {@code addAll(Collection c)} method merely returns {@code addAll(size,
* c)}.
*
*
The {@code listIterator(int)} method returns a "wrapper object"
* over a list iterator on the backing list, which is created with the
* corresponding method on the backing list. The {@code iterator} method
* merely returns {@code listIterator()}, and the {@code size} method
* merely returns the subclass's {@code size} field.
*
*
All methods first check to see if the actual {@code modCount} of
* the backing list is equal to its expected value, and throw a
* {@code ConcurrentModificationException} if it is not.
*
* @throws IndexOutOfBoundsException if an endpoint index value is out of range
* {@code (fromIndex < 0 || toIndex > size)}
* @throws IllegalArgumentException if the endpoint indices are out of order
* {@code (fromIndex > toIndex)}
*/
public List subList(int fromIndex, int toIndex) {
return (this instanceof RandomAccess ?
new RandomAccessSubList(this, fromIndex, toIndex) :
new SubList(this, fromIndex, toIndex));
}
// Comparison and hashing
/**
* Compares the specified object with this list for equality. Returns
* {@code true} if and only if the specified object is also a list, both
* lists have the same size, and all corresponding pairs of elements in
* the two lists are equal. (Two elements {@code e1} and
* {@code e2} are equal if {@code (e1==null ? e2==null :
* e1.equals(e2))}.) In other words, two lists are defined to be
* equal if they contain the same elements in the same order.
*
* This implementation first checks if the specified object is this
* list. If so, it returns {@code true}; if not, it checks if the
* specified object is a list. If not, it returns {@code false}; if so,
* it iterates over both lists, comparing corresponding pairs of elements.
* If any comparison returns {@code false}, this method returns
* {@code false}. If either iterator runs out of elements before the
* other it returns {@code false} (as the lists are of unequal length);
* otherwise it returns {@code true} when the iterations complete.
*
* @param o the object to be compared for equality with this list
* @return {@code true} if the specified object is equal to this list
*/
public boolean equals(Object o) {
if (o == this)
return true;
if (!(o instanceof List))
return false;
ListIterator e1 = listIterator();
ListIterator e2 = ((List) o).listIterator();
while(e1.hasNext() && e2.hasNext()) {
E o1 = e1.next();
Object o2 = e2.next();
if (!(o1==null ? o2==null : o1.equals(o2)))
return false;
}
return !(e1.hasNext() || e2.hasNext());
}
/**
* Returns the hash code value for this list.
*
* This implementation uses exactly the code that is used to define the
* list hash function in the documentation for the {@link List#hashCode}
* method.
*
* @return the hash code value for this list
*/
public int hashCode() {
int hashCode = 1;
Iterator it = this.iterator();
while (it.hasNext()) {
E e = it.next();
hashCode = 31*hashCode + (e==null ? 0 : e.hashCode());
}
return hashCode;
}
/**
* Removes from this list all of the elements whose index is between
* {@code fromIndex}, inclusive, and {@code toIndex}, exclusive.
* Shifts any succeeding elements to the left (reduces their index).
* This call shortens the list by {@code (toIndex - fromIndex)} elements.
* (If {@code toIndex==fromIndex}, this operation has no effect.)
*
* This method is called by the {@code clear} operation on this list
* and its subLists. Overriding this method to take advantage of
* the internals of the list implementation can substantially
* improve the performance of the {@code clear} operation on this list
* and its subLists.
*
*
This implementation gets a list iterator positioned before
* {@code fromIndex}, and repeatedly calls {@code ListIterator.next}
* followed by {@code ListIterator.remove} until the entire range has
* been removed. Note: if {@code ListIterator.remove} requires linear
* time, this implementation requires quadratic time.
*
* @param fromIndex index of first element to be removed
* @param toIndex index after last element to be removed
*/
protected void removeRange(int fromIndex, int toIndex) {
ListIterator it = listIterator(fromIndex);
for (int i=0, n=toIndex-fromIndex; istructurally modified.
* Structural modifications are those that change the size of the
* list, or otherwise perturb it in such a fashion that iterations in
* progress may yield incorrect results.
*
* This field is used by the iterator and list iterator implementation
* returned by the {@code iterator} and {@code listIterator} methods.
* If the value of this field changes unexpectedly, the iterator (or list
* iterator) will throw a {@code ConcurrentModificationException} in
* response to the {@code next}, {@code remove}, {@code previous},
* {@code set} or {@code add} operations. This provides
* fail-fast behavior, rather than non-deterministic behavior in
* the face of concurrent modification during iteration.
*
*
Use of this field by subclasses is optional. If a subclass
* wishes to provide fail-fast iterators (and list iterators), then it
* merely has to increment this field in its {@code add(int, E)} and
* {@code remove(int)} methods (and any other methods that it overrides
* that result in structural modifications to the list). A single call to
* {@code add(int, E)} or {@code remove(int)} must add no more than
* one to this field, or the iterators (and list iterators) will throw
* bogus {@code ConcurrentModificationExceptions}. If an implementation
* does not wish to provide fail-fast iterators, this field may be
* ignored.
*/
protected transient int modCount = 0;
private void rangeCheckForAdd(int index) {
if (index < 0 || index > size())
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private String outOfBoundsMsg(int index) {
return "";
}
}
class SubList extends AbstractList {
private final AbstractList l;
private final int offset;
private int size;
SubList(AbstractList list, int fromIndex, int toIndex) {
if (fromIndex < 0)
throw new IndexOutOfBoundsException();
if (toIndex > list.size())
throw new IndexOutOfBoundsException();
if (fromIndex > toIndex)
throw new IllegalArgumentException();
l = list;
offset = fromIndex;
size = toIndex - fromIndex;
this.modCount = l.modCount;
}
public E set(int index, E element) {
rangeCheck(index);
checkForComodification();
return l.set(index+offset, element);
}
public E get(int index) {
rangeCheck(index);
checkForComodification();
return l.get(index+offset);
}
public int size() {
checkForComodification();
return size;
}
public void add(int index, E element) {
rangeCheckForAdd(index);
checkForComodification();
l.add(index+offset, element);
this.modCount = l.modCount;
size++;
}
public E remove(int index) {
rangeCheck(index);
checkForComodification();
E result = l.remove(index+offset);
this.modCount = l.modCount;
size--;
return result;
}
protected void removeRange(int fromIndex, int toIndex) {
checkForComodification();
l.removeRange(fromIndex+offset, toIndex+offset);
this.modCount = l.modCount;
size -= (toIndex-fromIndex);
}
public boolean addAll(Collection c) {
return addAll(size, c);
}
public boolean addAll(int index, Collection c) {
rangeCheckForAdd(index);
int cSize = c.size();
if (cSize==0)
return false;
checkForComodification();
l.addAll(offset+index, c);
this.modCount = l.modCount;
size += cSize;
return true;
}
public Iterator iterator() {
return listIterator();
}
public ListIterator listIterator(final int index) {
checkForComodification();
rangeCheckForAdd(index);
return new ListIterator() {
private final ListIterator i = l.listIterator(index+offset);
public boolean hasNext() {
return nextIndex() < size;
}
public E next() {
if (hasNext())
return i.next();
else
throw new NoSuchElementException();
}
public boolean hasPrevious() {
return previousIndex() >= 0;
}
public E previous() {
if (hasPrevious())
return i.previous();
else
throw new NoSuchElementException();
}
public int nextIndex() {
return i.nextIndex() - offset;
}
public int previousIndex() {
return i.previousIndex() - offset;
}
public void remove() {
i.remove();
SubList.this.modCount = l.modCount;
size--;
}
public void set(E e) {
i.set(e);
}
public void add(E e) {
i.add(e);
SubList.this.modCount = l.modCount;
size++;
}
};
}
public List subList(int fromIndex, int toIndex) {
return new SubList(this, fromIndex, toIndex);
}
private void rangeCheck(int index) {
if (index < 0 || index >= size)
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private void rangeCheckForAdd(int index) {
if (index < 0 || index > size)
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private String outOfBoundsMsg(int index) {
return "";
}
private void checkForComodification() {
if (this.modCount != l.modCount)
throw new ConcurrentModificationException();
}
}
class RandomAccessSubList extends SubList implements RandomAccess {
RandomAccessSubList(AbstractList list, int fromIndex, int toIndex) {
super(list, fromIndex, toIndex);
}
public List subList(int fromIndex, int toIndex) {
return new RandomAccessSubList(this, fromIndex, toIndex);
}
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This class provides a skeletal implementation of the List
* interface to minimize the effort required to implement this interface
* backed by a "sequential access" data store (such as a linked list). For
* random access data (such as an array), AbstractList should be used
* in preference to this class.
*
* This class is the opposite of the AbstractList class in the sense
* that it implements the "random access" methods (get(int index),
* set(int index, E element), add(int index, E element) and
* remove(int index)) on top of the list's list iterator, instead of
* the other way around.
*
* To implement a list the programmer needs only to extend this class and
* provide implementations for the listIterator and size
* methods. For an unmodifiable list, the programmer need only implement the
* list iterator's hasNext, next, hasPrevious,
* previous and index methods.
*
* For a modifiable list the programmer should additionally implement the list
* iterator's set method. For a variable-size list the programmer
* should additionally implement the list iterator's remove and
* add methods.
*
* The programmer should generally provide a void (no argument) and collection
* constructor, as per the recommendation in the Collection interface
* specification.
*
* This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Collection
* @see List
* @see AbstractList
* @see AbstractCollection
* @since 1.2
*/
public abstract class AbstractSequentialList extends AbstractList {
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
protected AbstractSequentialList() {
}
/**
* Returns the element at the specified position in this list.
*
* This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it gets
* the element using ListIterator.next and returns it.
*
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E get(int index) {
try {
return listIterator(index).next();
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Replaces the element at the specified position in this list with the
* specified element (optional operation).
*
*
This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it gets
* the current element using ListIterator.next and replaces it
* with ListIterator.set.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the set operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
try {
ListIterator e = listIterator(index);
E oldVal = e.next();
e.set(element);
return oldVal;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Inserts the specified element at the specified position in this list
* (optional operation). Shifts the element currently at that position
* (if any) and any subsequent elements to the right (adds one to their
* indices).
*
* This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it
* inserts the specified element with ListIterator.add.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the add operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
try {
listIterator(index).add(element);
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
/**
* Removes the element at the specified position in this list (optional
* operation). Shifts any subsequent elements to the left (subtracts one
* from their indices). Returns the element that was removed from the
* list.
*
*
This implementation first gets a list iterator pointing to the
* indexed element (with listIterator(index)). Then, it removes
* the element with ListIterator.remove.
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator does not
* implement the remove operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
try {
ListIterator e = listIterator(index);
E outCast = e.next();
e.remove();
return outCast;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
// Bulk Operations
/**
* Inserts all of the elements in the specified collection into this
* list at the specified position (optional operation). Shifts the
* element currently at that position (if any) and any subsequent
* elements to the right (increases their indices). The new elements
* will appear in this list in the order that they are returned by the
* specified collection's iterator. The behavior of this operation is
* undefined if the specified collection is modified while the
* operation is in progress. (Note that this will occur if the specified
* collection is this list, and it's nonempty.)
*
* This implementation gets an iterator over the specified collection and
* a list iterator over this list pointing to the indexed element (with
* listIterator(index)). Then, it iterates over the specified
* collection, inserting the elements obtained from the iterator into this
* list, one at a time, using ListIterator.add followed by
* ListIterator.next (to skip over the added element).
*
*
Note that this implementation will throw an
* UnsupportedOperationException if the list iterator returned by
* the listIterator method does not implement the add
* operation.
*
* @throws UnsupportedOperationException {@inheritDoc}
* @throws ClassCastException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @throws IllegalArgumentException {@inheritDoc}
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public boolean addAll(int index, Collection c) {
try {
boolean modified = false;
ListIterator e1 = listIterator(index);
Iterator e2 = c.iterator();
while (e2.hasNext()) {
e1.add(e2.next());
modified = true;
}
return modified;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException();
}
}
// Iterators
/**
* Returns an iterator over the elements in this list (in proper
* sequence).
*
* This implementation merely returns a list iterator over the list.
*
* @return an iterator over the elements in this list (in proper sequence)
*/
public Iterator iterator() {
return listIterator();
}
/**
* Returns a list iterator over the elements in this list (in proper
* sequence).
*
* @param index index of first element to be returned from the list
* iterator (by a call to the next method)
* @return a list iterator over the elements in this list (in proper
* sequence)
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public abstract ListIterator listIterator(int index);
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* The root interface in the collection hierarchy. A collection
* represents a group of objects, known as its elements. Some
* collections allow duplicate elements and others do not. Some are ordered
* and others unordered. The JDK does not provide any direct
* implementations of this interface: it provides implementations of more
* specific subinterfaces like Set and List. This interface
* is typically used to pass collections around and manipulate them where
* maximum generality is desired.
*
* Bags or multisets (unordered collections that may contain
* duplicate elements) should implement this interface directly.
*
*
All general-purpose Collection implementation classes (which
* typically implement Collection indirectly through one of its
* subinterfaces) should provide two "standard" constructors: a void (no
* arguments) constructor, which creates an empty collection, and a
* constructor with a single argument of type Collection, which
* creates a new collection with the same elements as its argument. In
* effect, the latter constructor allows the user to copy any collection,
* producing an equivalent collection of the desired implementation type.
* There is no way to enforce this convention (as interfaces cannot contain
* constructors) but all of the general-purpose Collection
* implementations in the Java platform libraries comply.
*
*
The "destructive" methods contained in this interface, that is, the
* methods that modify the collection on which they operate, are specified to
* throw UnsupportedOperationException if this collection does not
* support the operation. If this is the case, these methods may, but are not
* required to, throw an UnsupportedOperationException if the
* invocation would have no effect on the collection. For example, invoking
* the {@link #addAll(Collection)} method on an unmodifiable collection may,
* but is not required to, throw the exception if the collection to be added
* is empty.
*
*
Some collection implementations have restrictions on the elements that
* they may contain. For example, some implementations prohibit null elements,
* and some have restrictions on the types of their elements. Attempting to
* add an ineligible element throws an unchecked exception, typically
* NullPointerException or ClassCastException. Attempting
* to query the presence of an ineligible element may throw an exception,
* or it may simply return false; some implementations will exhibit the former
* behavior and some will exhibit the latter. More generally, attempting an
* operation on an ineligible element whose completion would not result in
* the insertion of an ineligible element into the collection may throw an
* exception or it may succeed, at the option of the implementation.
* Such exceptions are marked as "optional" in the specification for this
* interface.
*
*
It is up to each collection to determine its own synchronization
* policy. In the absence of a stronger guarantee by the
* implementation, undefined behavior may result from the invocation
* of any method on a collection that is being mutated by another
* thread; this includes direct invocations, passing the collection to
* a method that might perform invocations, and using an existing
* iterator to examine the collection.
*
*
Many methods in Collections Framework interfaces are defined in
* terms of the {@link Object#equals(Object) equals} method. For example,
* the specification for the {@link #contains(Object) contains(Object o)}
* method says: "returns true if and only if this collection
* contains at least one element e such that
* (o==null ? e==null : o.equals(e))." This specification should
* not be construed to imply that invoking Collection.contains
* with a non-null argument o will cause o.equals(e) to be
* invoked for any element e. Implementations are free to implement
* optimizations whereby the equals invocation is avoided, for
* example, by first comparing the hash codes of the two elements. (The
* {@link Object#hashCode()} specification guarantees that two objects with
* unequal hash codes cannot be equal.) More generally, implementations of
* the various Collections Framework interfaces are free to take advantage of
* the specified behavior of underlying {@link Object} methods wherever the
* implementor deems it appropriate.
*
*
This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @author Neal Gafter
* @see Set
* @see List
* @see Map
* @see SortedSet
* @see SortedMap
* @see HashSet
* @see TreeSet
* @see ArrayList
* @see LinkedList
* @see Vector
* @see Collections
* @see Arrays
* @see AbstractCollection
* @since 1.2
*/
public interface Collection {
// Query Operations
/**
* Returns the number of elements in this collection. If this collection
* contains more than Integer.MAX_VALUE elements, returns
* Integer.MAX_VALUE.
*
* @return the number of elements in this collection
*/
int size();
/**
* Returns true if this collection contains no elements.
*
* @return true if this collection contains no elements
*/
boolean isEmpty();
/**
* Returns true if this collection contains the specified element.
* More formally, returns true if and only if this collection
* contains at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this collection is to be tested
* @return true if this collection contains the specified
* element
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection (optional)
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements (optional)
*/
boolean contains(Object o);
/**
* Returns an iterator over the elements in this collection. There are no
* guarantees concerning the order in which the elements are returned
* (unless this collection is an instance of some class that provides a
* guarantee).
*
* @return an Iterator over the elements in this collection
*/
Iterator iterator();
// Modification Operations
/**
* Ensures that this collection contains the specified element (optional
* operation). Returns true if this collection changed as a
* result of the call. (Returns false if this collection does
* not permit duplicates and already contains the specified element.)
*
* Collections that support this operation may place limitations on what
* elements may be added to this collection. In particular, some
* collections will refuse to add null elements, and others will
* impose restrictions on the type of elements that may be added.
* Collection classes should clearly specify in their documentation any
* restrictions on what elements may be added.
*
* If a collection refuses to add a particular element for any reason
* other than that it already contains the element, it must throw
* an exception (rather than returning false). This preserves
* the invariant that a collection always contains the specified element
* after this call returns.
*
* @param e element whose presence in this collection is to be ensured
* @return true if this collection changed as a result of the
* call
* @throws UnsupportedOperationException if the add operation
* is not supported by this collection
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this collection
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements
* @throws IllegalArgumentException if some property of the element
* prevents it from being added to this collection
* @throws IllegalStateException if the element cannot be added at this
* time due to insertion restrictions
*/
boolean add(E e);
/**
* Removes a single instance of the specified element from this
* collection, if it is present (optional operation). More formally,
* removes an element e such that
* (o==null ? e==null : o.equals(e)), if
* this collection contains one or more such elements. Returns
* true if this collection contained the specified element (or
* equivalently, if this collection changed as a result of the call).
*
* @param o element to be removed from this collection, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the type of the specified element
* is incompatible with this collection (optional)
* @throws NullPointerException if the specified element is null and this
* collection does not permit null elements (optional)
* @throws UnsupportedOperationException if the remove operation
* is not supported by this collection
*/
boolean remove(Object o);
// Bulk Operations
/**
* Returns true if this collection contains all of the elements
* in the specified collection.
*
* @param c collection to be checked for containment in this collection
* @return true if this collection contains all of the elements
* in the specified collection
* @throws ClassCastException if the types of one or more elements
* in the specified collection are incompatible with this
* collection (optional)
* @throws NullPointerException if the specified collection contains one
* or more null elements and this collection does not permit null
* elements (optional), or if the specified collection is null
* @see #contains(Object)
*/
boolean containsAll(Collection c);
/**
* Adds all of the elements in the specified collection to this collection
* (optional operation). The behavior of this operation is undefined if
* the specified collection is modified while the operation is in progress.
* (This implies that the behavior of this call is undefined if the
* specified collection is this collection, and this collection is
* nonempty.)
*
* @param c collection containing elements to be added to this collection
* @return true if this collection changed as a result of the call
* @throws UnsupportedOperationException if the addAll operation
* is not supported by this collection
* @throws ClassCastException if the class of an element of the specified
* collection prevents it from being added to this collection
* @throws NullPointerException if the specified collection contains a
* null element and this collection does not permit null elements,
* or if the specified collection is null
* @throws IllegalArgumentException if some property of an element of the
* specified collection prevents it from being added to this
* collection
* @throws IllegalStateException if not all the elements can be added at
* this time due to insertion restrictions
* @see #add(Object)
*/
boolean addAll(Collection c);
/**
* Removes all of this collection's elements that are also contained in the
* specified collection (optional operation). After this call returns,
* this collection will contain no elements in common with the specified
* collection.
*
* @param c collection containing elements to be removed from this collection
* @return true if this collection changed as a result of the
* call
* @throws UnsupportedOperationException if the removeAll method
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection (optional)
* @throws NullPointerException if this collection contains one or more
* null elements and the specified collection does not support
* null elements (optional), or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean removeAll(Collection c);
/**
* Retains only the elements in this collection that are contained in the
* specified collection (optional operation). In other words, removes from
* this collection all of its elements that are not contained in the
* specified collection.
*
* @param c collection containing elements to be retained in this collection
* @return true if this collection changed as a result of the call
* @throws UnsupportedOperationException if the retainAll operation
* is not supported by this collection
* @throws ClassCastException if the types of one or more elements
* in this collection are incompatible with the specified
* collection (optional)
* @throws NullPointerException if this collection contains one or more
* null elements and the specified collection does not permit null
* elements (optional), or if the specified collection is null
* @see #remove(Object)
* @see #contains(Object)
*/
boolean retainAll(Collection c);
/**
* Removes all of the elements from this collection (optional operation).
* The collection will be empty after this method returns.
*
* @throws UnsupportedOperationException if the clear operation
* is not supported by this collection
*/
void clear();
// Comparison and hashing
/**
* Compares the specified object with this collection for equality.
*
* While the Collection interface adds no stipulations to the
* general contract for the Object.equals, programmers who
* implement the Collection interface "directly" (in other words,
* create a class that is a Collection but is not a Set
* or a List) must exercise care if they choose to override the
* Object.equals. It is not necessary to do so, and the simplest
* course of action is to rely on Object's implementation, but
* the implementor may wish to implement a "value comparison" in place of
* the default "reference comparison." (The List and
* Set interfaces mandate such value comparisons.)
*
* The general contract for the Object.equals method states that
* equals must be symmetric (in other words, a.equals(b) if and
* only if b.equals(a)). The contracts for List.equals
* and Set.equals state that lists are only equal to other lists,
* and sets to other sets. Thus, a custom equals method for a
* collection class that implements neither the List nor
* Set interface must return false when this collection
* is compared to any list or set. (By the same logic, it is not possible
* to write a class that correctly implements both the Set and
* List interfaces.)
*
* @param o object to be compared for equality with this collection
* @return true if the specified object is equal to this
* collection
*
* @see Object#equals(Object)
* @see Set#equals(Object)
* @see List#equals(Object)
*/
boolean equals(Object o);
/**
* Returns the hash code value for this collection. While the
* Collection interface adds no stipulations to the general
* contract for the Object.hashCode method, programmers should
* take note that any class that overrides the Object.equals
* method must also override the Object.hashCode method in order
* to satisfy the general contract for the Object.hashCodemethod.
* In particular, c1.equals(c2) implies that
* c1.hashCode()==c2.hashCode().
*
* @return the hash code value for this collection
*
* @see Object#hashCode()
* @see Object#equals(Object)
*/
int hashCode();
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* This exception may be thrown by methods that have detected concurrent
* modification of an object when such modification is not permissible.
*
* For example, it is not generally permissible for one thread to modify a Collection
* while another thread is iterating over it. In general, the results of the
* iteration are undefined under these circumstances. Some Iterator
* implementations (including those of all the general purpose collection implementations
* provided by the JRE) may choose to throw this exception if this behavior is
* detected. Iterators that do this are known as fail-fast iterators,
* as they fail quickly and cleanly, rather that risking arbitrary,
* non-deterministic behavior at an undetermined time in the future.
*
* Note that this exception does not always indicate that an object has
* been concurrently modified by a different thread. If a single
* thread issues a sequence of method invocations that violates the
* contract of an object, the object may throw this exception. For
* example, if a thread modifies a collection directly while it is
* iterating over the collection with a fail-fast iterator, the iterator
* will throw this exception.
*
*
Note that fail-fast behavior cannot be guaranteed as it is, generally
* speaking, impossible to make any hard guarantees in the presence of
* unsynchronized concurrent modification. Fail-fast operations
* throw ConcurrentModificationException on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: ConcurrentModificationException
* should be used only to detect bugs.
*
* @author Josh Bloch
* @see Collection
* @see Iterator
* @see ListIterator
* @see Vector
* @see LinkedList
* @see HashSet
* @see Hashtable
* @see TreeMap
* @see AbstractList
* @since 1.2
*/
public class ConcurrentModificationException extends RuntimeException {
/**
* Constructs a ConcurrentModificationException with no
* detail message.
*/
public ConcurrentModificationException() {
}
/**
* Constructs a ConcurrentModificationException with the
* specified detail message.
*
* @param message the detail message pertaining to this exception.
*/
public ConcurrentModificationException(String message) {
super(message);
}
}
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* Written by Doug Lea and Josh Bloch with assistance from members of
* JCP JSR-166 Expert Group and released to the public domain, as explained
* at http://creativecommons.org/licenses/publicdomain
*/
package javaUtilEx;
/**
* A linear collection that supports element insertion and removal at
* both ends. The name deque is short for "double ended queue"
* and is usually pronounced "deck". Most Deque
* implementations place no fixed limits on the number of elements
* they may contain, but this interface supports capacity-restricted
* deques as well as those with no fixed size limit.
*
*
This interface defines methods to access the elements at both
* ends of the deque. Methods are provided to insert, remove, and
* examine the element. Each of these methods exists in two forms:
* one throws an exception if the operation fails, the other returns a
* special value (either null or false, depending on
* the operation). The latter form of the insert operation is
* designed specifically for use with capacity-restricted
* Deque implementations; in most implementations, insert
* operations cannot fail.
*
*
The twelve methods described above are summarized in the
* following table:
*
*
*
*
* |
* First Element (Head) |
* Last Element (Tail) |
*
*
* |
* Throws exception |
* Special value |
* Throws exception |
* Special value |
*
*
* | Insert |
* {@link #addFirst addFirst(e)} |
* {@link #offerFirst offerFirst(e)} |
* {@link #addLast addLast(e)} |
* {@link #offerLast offerLast(e)} |
*
*
* | Remove |
* {@link #removeFirst removeFirst()} |
* {@link #pollFirst pollFirst()} |
* {@link #removeLast removeLast()} |
* {@link #pollLast pollLast()} |
*
*
* | Examine |
* {@link #getFirst getFirst()} |
* {@link #peekFirst peekFirst()} |
* {@link #getLast getLast()} |
* {@link #peekLast peekLast()} |
*
*
*
* This interface extends the {@link Queue} interface. When a deque is
* used as a queue, FIFO (First-In-First-Out) behavior results. Elements are
* added at the end of the deque and removed from the beginning. The methods
* inherited from the Queue interface are precisely equivalent to
* Deque methods as indicated in the following table:
*
*
*
*
* | Queue Method |
* Equivalent Deque Method |
*
*
* | {@link java.util.Queue#add add(e)} |
* {@link #addLast addLast(e)} |
*
*
* | {@link java.util.Queue#offer offer(e)} |
* {@link #offerLast offerLast(e)} |
*
*
* | {@link java.util.Queue#remove remove()} |
* {@link #removeFirst removeFirst()} |
*
*
* | {@link java.util.Queue#poll poll()} |
* {@link #pollFirst pollFirst()} |
*
*
* | {@link java.util.Queue#element element()} |
* {@link #getFirst getFirst()} |
*
*
* | {@link java.util.Queue#peek peek()} |
* {@link #peek peekFirst()} |
*
*
*
* Deques can also be used as LIFO (Last-In-First-Out) stacks. This
* interface should be used in preference to the legacy {@link Stack} class.
* When a deque is used as a stack, elements are pushed and popped from the
* beginning of the deque. Stack methods are precisely equivalent to
* Deque methods as indicated in the table below:
*
*
*
*
* | Stack Method |
* Equivalent Deque Method |
*
*
* | {@link #push push(e)} |
* {@link #addFirst addFirst(e)} |
*
*
* | {@link #pop pop()} |
* {@link #removeFirst removeFirst()} |
*
*
* | {@link #peek peek()} |
* {@link #peekFirst peekFirst()} |
*
*
*
* Note that the {@link #peek peek} method works equally well when
* a deque is used as a queue or a stack; in either case, elements are
* drawn from the beginning of the deque.
*
*
This interface provides two methods to remove interior
* elements, {@link #removeFirstOccurrence removeFirstOccurrence} and
* {@link #removeLastOccurrence removeLastOccurrence}.
*
*
Unlike the {@link List} interface, this interface does not
* provide support for indexed access to elements.
*
*
While Deque implementations are not strictly required
* to prohibit the insertion of null elements, they are strongly
* encouraged to do so. Users of any Deque implementations
* that do allow null elements are strongly encouraged not to
* take advantage of the ability to insert nulls. This is so because
* null is used as a special return value by various methods
* to indicated that the deque is empty.
*
*
Deque implementations generally do not define
* element-based versions of the equals and hashCode
* methods, but instead inherit the identity-based versions from class
* Object.
*
*
This interface is a member of the Java Collections
* Framework.
*
* @author Doug Lea
* @author Josh Bloch
* @since 1.6
* @param the type of elements held in this collection
*/
public interface Deque extends Queue {
/**
* Inserts the specified element at the front of this deque if it is
* possible to do so immediately without violating capacity restrictions.
* When using a capacity-restricted deque, it is generally preferable to
* use method {@link #offerFirst}.
*
* @param e the element to add
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void addFirst(E e);
/**
* Inserts the specified element at the end of this deque if it is
* possible to do so immediately without violating capacity restrictions.
* When using a capacity-restricted deque, it is generally preferable to
* use method {@link #offerLast}.
*
* This method is equivalent to {@link #add}.
*
* @param e the element to add
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void addLast(E e);
/**
* Inserts the specified element at the front of this deque unless it would
* violate capacity restrictions. When using a capacity-restricted deque,
* this method is generally preferable to the {@link #addFirst} method,
* which can fail to insert an element only by throwing an exception.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offerFirst(E e);
/**
* Inserts the specified element at the end of this deque unless it would
* violate capacity restrictions. When using a capacity-restricted deque,
* this method is generally preferable to the {@link #addLast} method,
* which can fail to insert an element only by throwing an exception.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offerLast(E e);
/**
* Retrieves and removes the first element of this deque. This method
* differs from {@link #pollFirst pollFirst} only in that it throws an
* exception if this deque is empty.
*
* @return the head of this deque
* @throws NoSuchElementException if this deque is empty
*/
E removeFirst();
/**
* Retrieves and removes the last element of this deque. This method
* differs from {@link #pollLast pollLast} only in that it throws an
* exception if this deque is empty.
*
* @return the tail of this deque
* @throws NoSuchElementException if this deque is empty
*/
E removeLast();
/**
* Retrieves and removes the first element of this deque,
* or returns null if this deque is empty.
*
* @return the head of this deque, or null if this deque is empty
*/
E pollFirst();
/**
* Retrieves and removes the last element of this deque,
* or returns null if this deque is empty.
*
* @return the tail of this deque, or null if this deque is empty
*/
E pollLast();
/**
* Retrieves, but does not remove, the first element of this deque.
*
* This method differs from {@link #peekFirst peekFirst} only in that it
* throws an exception if this deque is empty.
*
* @return the head of this deque
* @throws NoSuchElementException if this deque is empty
*/
E getFirst();
/**
* Retrieves, but does not remove, the last element of this deque.
* This method differs from {@link #peekLast peekLast} only in that it
* throws an exception if this deque is empty.
*
* @return the tail of this deque
* @throws NoSuchElementException if this deque is empty
*/
E getLast();
/**
* Retrieves, but does not remove, the first element of this deque,
* or returns null if this deque is empty.
*
* @return the head of this deque, or null if this deque is empty
*/
E peekFirst();
/**
* Retrieves, but does not remove, the last element of this deque,
* or returns null if this deque is empty.
*
* @return the tail of this deque, or null if this deque is empty
*/
E peekLast();
/**
* Removes the first occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the first element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean removeFirstOccurrence(Object o);
/**
* Removes the last occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the last element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean removeLastOccurrence(Object o);
// *** Queue methods ***
/**
* Inserts the specified element into the queue represented by this deque
* (in other words, at the tail of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and throwing an
* IllegalStateException if no space is currently available.
* When using a capacity-restricted deque, it is generally preferable to
* use {@link #offer(Object) offer}.
*
*
This method is equivalent to {@link #addLast}.
*
* @param e the element to add
* @return true (as specified by {@link Collection#add})
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean add(E e);
/**
* Inserts the specified element into the queue represented by this deque
* (in other words, at the tail of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and false if no space is currently
* available. When using a capacity-restricted deque, this method is
* generally preferable to the {@link #add} method, which can fail to
* insert an element only by throwing an exception.
*
*
This method is equivalent to {@link #offerLast}.
*
* @param e the element to add
* @return true if the element was added to this deque, else
* false
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
boolean offer(E e);
/**
* Retrieves and removes the head of the queue represented by this deque
* (in other words, the first element of this deque).
* This method differs from {@link #poll poll} only in that it throws an
* exception if this deque is empty.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the head of the queue represented by this deque
* @throws NoSuchElementException if this deque is empty
*/
E remove();
/**
* Retrieves and removes the head of the queue represented by this deque
* (in other words, the first element of this deque), or returns
* null if this deque is empty.
*
*
This method is equivalent to {@link #pollFirst()}.
*
* @return the first element of this deque, or null if
* this deque is empty
*/
E poll();
/**
* Retrieves, but does not remove, the head of the queue represented by
* this deque (in other words, the first element of this deque).
* This method differs from {@link #peek peek} only in that it throws an
* exception if this deque is empty.
*
*
This method is equivalent to {@link #getFirst()}.
*
* @return the head of the queue represented by this deque
* @throws NoSuchElementException if this deque is empty
*/
E element();
/**
* Retrieves, but does not remove, the head of the queue represented by
* this deque (in other words, the first element of this deque), or
* returns null if this deque is empty.
*
*
This method is equivalent to {@link #peekFirst()}.
*
* @return the head of the queue represented by this deque, or
* null if this deque is empty
*/
E peek();
// *** Stack methods ***
/**
* Pushes an element onto the stack represented by this deque (in other
* words, at the head of this deque) if it is possible to do so
* immediately without violating capacity restrictions, returning
* true upon success and throwing an
* IllegalStateException if no space is currently available.
*
*
This method is equivalent to {@link #addFirst}.
*
* @param e the element to push
* @throws IllegalStateException if the element cannot be added at this
* time due to capacity restrictions
* @throws ClassCastException if the class of the specified element
* prevents it from being added to this deque
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements
* @throws IllegalArgumentException if some property of the specified
* element prevents it from being added to this deque
*/
void push(E e);
/**
* Pops an element from the stack represented by this deque. In other
* words, removes and returns the first element of this deque.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the element at the front of this deque (which is the top
* of the stack represented by this deque)
* @throws NoSuchElementException if this deque is empty
*/
E pop();
// *** Collection methods ***
/**
* Removes the first occurrence of the specified element from this deque.
* If the deque does not contain the element, it is unchanged.
* More formally, removes the first element e such that
* (o==null ? e==null : o.equals(e))
* (if such an element exists).
* Returns true if this deque contained the specified element
* (or equivalently, if this deque changed as a result of the call).
*
*
This method is equivalent to {@link #removeFirstOccurrence}.
*
* @param o element to be removed from this deque, if present
* @return true if an element was removed as a result of this call
* @throws ClassCastException if the class of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean remove(Object o);
/**
* Returns true if this deque contains the specified element.
* More formally, returns true if and only if this deque contains
* at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this deque is to be tested
* @return true if this deque contains the specified element
* @throws ClassCastException if the type of the specified element
* is incompatible with this deque (optional)
* @throws NullPointerException if the specified element is null and this
* deque does not permit null elements (optional)
*/
boolean contains(Object o);
/**
* Returns the number of elements in this deque.
*
* @return the number of elements in this deque
*/
public int size();
/**
* Returns an iterator over the elements in this deque in proper sequence.
* The elements will be returned in order from first (head) to last (tail).
*
* @return an iterator over the elements in this deque in proper sequence
*/
Iterator iterator();
/**
* Returns an iterator over the elements in this deque in reverse
* sequential order. The elements will be returned in order from
* last (tail) to first (head).
*
* @return an iterator over the elements in this deque in reverse
* sequence
*/
Iterator descendingIterator();
}
/*
* Copyright 1994-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Thrown to indicate that a method has been passed an illegal or
* inappropriate argument.
*
* @author unascribed
* @see java.lang.Thread#setPriority(int)
* @since JDK1.0
*/
public
class IllegalArgumentException extends RuntimeException {
/**
* Constructs an IllegalArgumentException with no
* detail message.
*/
public IllegalArgumentException() {
super();
}
/**
* Constructs an IllegalArgumentException with the
* specified detail message.
*
* @param s the detail message.
*/
public IllegalArgumentException(String s) {
super(s);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
* Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalArgumentException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of (cause==null ? null : cause.toString()) (which
* typically contains the class and detail message of cause).
* This constructor is useful for exceptions that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalArgumentException(Throwable cause) {
super(cause);
}
private static final long serialVersionUID = -5365630128856068164L;
}
/*
* Copyright 1996-2003 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Signals that a method has been invoked at an illegal or
* inappropriate time. In other words, the Java environment or
* Java application is not in an appropriate state for the requested
* operation.
*
* @author Jonni Kanerva
* @since JDK1.1
*/
public
class IllegalStateException extends RuntimeException {
/**
* Constructs an IllegalStateException with no detail message.
* A detail message is a String that describes this particular exception.
*/
public IllegalStateException() {
super();
}
/**
* Constructs an IllegalStateException with the specified detail
* message. A detail message is a String that describes this particular
* exception.
*
* @param s the String that contains a detailed message
*/
public IllegalStateException(String s) {
super(s);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
*
Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalStateException(String message, Throwable cause) {
super(message, cause);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of (cause==null ? null : cause.toString()) (which
* typically contains the class and detail message of cause).
* This constructor is useful for exceptions that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A null value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.5
*/
public IllegalStateException(Throwable cause) {
super(cause);
}
static final long serialVersionUID = -1848914673093119416L;
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* An iterator over a collection. {@code Iterator} takes the place of
* {@link Enumeration} in the Java Collections Framework. Iterators
* differ from enumerations in two ways:
*
*
* - Iterators allow the caller to remove elements from the
* underlying collection during the iteration with well-defined
* semantics.
*
- Method names have been improved.
*
*
* This interface is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @see Collection
* @see ListIterator
* @see Iterable
* @since 1.2
*/
public interface Iterator {
/**
* Returns {@code true} if the iteration has more elements.
* (In other words, returns {@code true} if {@link #next} would
* return an element rather than throwing an exception.)
*
* @return {@code true} if the iteration has more elements
*/
boolean hasNext();
/**
* Returns the next element in the iteration.
*
* @return the next element in the iteration
* @throws NoSuchElementException if the iteration has no more elements
*/
E next();
/**
* Removes from the underlying collection the last element returned
* by this iterator (optional operation). This method can be called
* only once per call to {@link #next}. The behavior of an iterator
* is unspecified if the underlying collection is modified while the
* iteration is in progress in any way other than by calling this
* method.
*
* @throws UnsupportedOperationException if the {@code remove}
* operation is not supported by this iterator
*
* @throws IllegalStateException if the {@code next} method has not
* yet been called, or the {@code remove} method has already
* been called after the last call to the {@code next}
* method
*/
void remove();
}
package javaUtilEx;
public class juLinkedListCreateIsEmpty {
public static void main(String[] args) {
Random.args = args;
LinkedList l = createList(Random.random());
l.isEmpty();
}
public static LinkedList createList(int n) {
LinkedList l = new LinkedList();
while (n > 0) {
l.addLast(new Content(Random.random()));
n--;
}
return l;
}
}
final class Content {
int val;
public Content(int v) {
this.val = v;
}
public int hashCode() {
return val^31;
}
public boolean equals(Object o) {
if (o instanceof Content) {
return this.val == ((Content) o).val;
}
return false;
}
}
/*
* Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package javaUtilEx;
/**
* Linked list implementation of the List interface. Implements all
* optional list operations, and permits all elements (including
* null). In addition to implementing the List interface,
* the LinkedList class provides uniformly named methods to
* get, remove and insert an element at the
* beginning and end of the list. These operations allow linked lists to be
* used as a stack, {@linkplain Queue queue}, or {@linkplain Deque
* double-ended queue}.
*
* The class implements the Deque interface, providing
* first-in-first-out queue operations for add,
* poll, along with other stack and deque operations.
*
* All of the operations perform as could be expected for a doubly-linked
* list. Operations that index into the list will traverse the list from
* the beginning or the end, whichever is closer to the specified index.
*
*
Note that this implementation is not synchronized.
* If multiple threads access a linked list concurrently, and at least
* one of the threads modifies the list structurally, it must be
* synchronized externally. (A structural modification is any operation
* that adds or deletes one or more elements; merely setting the value of
* an element is not a structural modification.) This is typically
* accomplished by synchronizing on some object that naturally
* encapsulates the list.
*
* If no such object exists, the list should be "wrapped" using the
* {@link Collections#synchronizedList Collections.synchronizedList}
* method. This is best done at creation time, to prevent accidental
* unsynchronized access to the list:
* List list = Collections.synchronizedList(new LinkedList(...));
*
* The iterators returned by this class's iterator and
* listIterator methods are fail-fast: if the list is
* structurally modified at any time after the iterator is created, in
* any way except through the Iterator's own remove or
* add methods, the iterator will throw a {@link
* ConcurrentModificationException}. Thus, in the face of concurrent
* modification, the iterator fails quickly and cleanly, rather than
* risking arbitrary, non-deterministic behavior at an undetermined
* time in the future.
*
*
Note that the fail-fast behavior of an iterator cannot be guaranteed
* as it is, generally speaking, impossible to make any hard guarantees in the
* presence of unsynchronized concurrent modification. Fail-fast iterators
* throw ConcurrentModificationException on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: the fail-fast behavior of iterators
* should be used only to detect bugs.
*
*
This class is a member of the
*
* Java Collections Framework.
*
* @author Josh Bloch
* @see List
* @see ArrayList
* @see Vector
* @since 1.2
* @param the type of elements held in this collection
*/
public class LinkedList
extends AbstractSequentialList
implements List, Deque
{
private transient Entry header = new Entry(null, null, null);
private transient int size = 0;
/**
* Constructs an empty list.
*/
public LinkedList() {
header.next = header.previous = header;
}
/**
* Constructs a list containing the elements of the specified
* collection, in the order they are returned by the collection's
* iterator.
*
* @param c the collection whose elements are to be placed into this list
* @throws NullPointerException if the specified collection is null
*/
public LinkedList(Collection c) {
this();
addAll(c);
}
/**
* Returns the first element in this list.
*
* @return the first element in this list
* @throws NoSuchElementException if this list is empty
*/
public E getFirst() {
if (size==0)
throw new NoSuchElementException();
return header.next.element;
}
/**
* Returns the last element in this list.
*
* @return the last element in this list
* @throws NoSuchElementException if this list is empty
*/
public E getLast() {
if (size==0)
throw new NoSuchElementException();
return header.previous.element;
}
/**
* Removes and returns the first element from this list.
*
* @return the first element from this list
* @throws NoSuchElementException if this list is empty
*/
public E removeFirst() {
return remove(header.next);
}
/**
* Removes and returns the last element from this list.
*
* @return the last element from this list
* @throws NoSuchElementException if this list is empty
*/
public E removeLast() {
return remove(header.previous);
}
/**
* Inserts the specified element at the beginning of this list.
*
* @param e the element to add
*/
public void addFirst(E e) {
addBefore(e, header.next);
}
/**
* Appends the specified element to the end of this list.
*
* This method is equivalent to {@link #add}.
*
* @param e the element to add
*/
public void addLast(E e) {
addBefore(e, header);
}
/**
* Returns true if this list contains the specified element.
* More formally, returns true if and only if this list contains
* at least one element e such that
* (o==null ? e==null : o.equals(e)).
*
* @param o element whose presence in this list is to be tested
* @return true if this list contains the specified element
*/
public boolean contains(Object o) {
return indexOf(o) != -1;
}
/**
* Returns the number of elements in this list.
*
* @return the number of elements in this list
*/
public int size() {
return size;
}
/**
* Appends the specified element to the end of this list.
*
*
This method is equivalent to {@link #addLast}.
*
* @param e element to be appended to this list
* @return true (as specified by {@link Collection#add})
*/
public boolean add(E e) {
addBefore(e, header);
return true;
}
/**
* Removes the first occurrence of the specified element from this list,
* if it is present. If this list does not contain the element, it is
* unchanged. More formally, removes the element with the lowest index
* i such that
* (o==null ? get(i)==null : o.equals(get(i)))
* (if such an element exists). Returns true if this list
* contained the specified element (or equivalently, if this list
* changed as a result of the call).
*
* @param o element to be removed from this list, if present
* @return true if this list contained the specified element
*/
public boolean remove(Object o) {
if (o==null) {
for (Entry e = header.next; e != header; e = e.next) {
if (e.element==null) {
remove(e);
return true;
}
}
} else {
for (Entry e = header.next; e != header; e = e.next) {
if (o.equals(e.element)) {
remove(e);
return true;
}
}
}
return false;
}
/**
* Removes all of the elements from this list.
*/
public void clear() {
Entry e = header.next;
while (e != header) {
Entry next = e.next;
e.next = e.previous = null;
e.element = null;
e = next;
}
header.next = header.previous = header;
size = 0;
modCount++;
}
// Positional Access Operations
/**
* Returns the element at the specified position in this list.
*
* @param index index of the element to return
* @return the element at the specified position in this list
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E get(int index) {
return entry(index).element;
}
/**
* Replaces the element at the specified position in this list with the
* specified element.
*
* @param index index of the element to replace
* @param element element to be stored at the specified position
* @return the element previously at the specified position
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E set(int index, E element) {
Entry e = entry(index);
E oldVal = e.element;
e.element = element;
return oldVal;
}
/**
* Inserts the specified element at the specified position in this list.
* Shifts the element currently at that position (if any) and any
* subsequent elements to the right (adds one to their indices).
*
* @param index index at which the specified element is to be inserted
* @param element element to be inserted
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public void add(int index, E element) {
addBefore(element, (index==size ? header : entry(index)));
}
/**
* Removes the element at the specified position in this list. Shifts any
* subsequent elements to the left (subtracts one from their indices).
* Returns the element that was removed from the list.
*
* @param index the index of the element to be removed
* @return the element previously at the specified position
* @throws IndexOutOfBoundsException {@inheritDoc}
*/
public E remove(int index) {
return remove(entry(index));
}
/**
* Returns the indexed entry.
*/
private Entry entry(int index) {
if (index < 0 || index >= size)
throw new IndexOutOfBoundsException();
Entry e = header;
if (index < (size >> 1)) {
for (int i = 0; i <= index; i++)
e = e.next;
} else {
for (int i = size; i > index; i--)
e = e.previous;
}
return e;
}
// Search Operations
/**
* Returns the index of the first occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the lowest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the first occurrence of the specified element in
* this list, or -1 if this list does not contain the element
*/
public int indexOf(Object o) {
int index = 0;
if (o==null) {
for (Entry e = header.next; e != header; e = e.next) {
if (e.element==null)
return index;
index++;
}
} else {
for (Entry e = header.next; e != header; e = e.next) {
if (o.equals(e.element))
return index;
index++;
}
}
return -1;
}
/**
* Returns the index of the last occurrence of the specified element
* in this list, or -1 if this list does not contain the element.
* More formally, returns the highest index i such that
* (o==null ? get(i)==null : o.equals(get(i))),
* or -1 if there is no such index.
*
* @param o element to search for
* @return the index of the last occurrence of the specified element in
* this list, or -1 if this list does not contain the element
*/
public int lastIndexOf(Object o) {
int index = size;
if (o==null) {
for (Entry e = header.previous; e != header; e = e.previous) {
index--;
if (e.element==null)
return index;
}
} else {
for (Entry e = header.previous; e != header; e = e.previous) {
index--;
if (o.equals(e.element))
return index;
}
}
return -1;
}
// Queue operations.
/**
* Retrieves, but does not remove, the head (first element) of this list.
* @return the head of this list, or null if this list is empty
* @since 1.5
*/
public E peek() {
if (size==0)
return null;
return getFirst();
}
/**
* Retrieves, but does not remove, the head (first element) of this list.
* @return the head of this list
* @throws NoSuchElementException if this list is empty
* @since 1.5
*/
public E element() {
return getFirst();
}
/**
* Retrieves and removes the head (first element) of this list
* @return the head of this list, or null if this list is empty
* @since 1.5
*/
public E poll() {
if (size==0)
return null;
return removeFirst();
}
/**
* Retrieves and removes the head (first element) of this list.
*
* @return the head of this list
* @throws NoSuchElementException if this list is empty
* @since 1.5
*/
public E remove() {
return removeFirst();
}
/**
* Adds the specified element as the tail (last element) of this list.
*
* @param e the element to add
* @return true (as specified by {@link Queue#offer})
* @since 1.5
*/
public boolean offer(E e) {
return add(e);
}
// Deque operations
/**
* Inserts the specified element at the front of this list.
*
* @param e the element to insert
* @return true (as specified by {@link Deque#offerFirst})
* @since 1.6
*/
public boolean offerFirst(E e) {
addFirst(e);
return true;
}
/**
* Inserts the specified element at the end of this list.
*
* @param e the element to insert
* @return true (as specified by {@link Deque#offerLast})
* @since 1.6
*/
public boolean offerLast(E e) {
addLast(e);
return true;
}
/**
* Retrieves, but does not remove, the first element of this list,
* or returns null if this list is empty.
*
* @return the first element of this list, or null
* if this list is empty
* @since 1.6
*/
public E peekFirst() {
if (size==0)
return null;
return getFirst();
}
/**
* Retrieves, but does not remove, the last element of this list,
* or returns null if this list is empty.
*
* @return the last element of this list, or null
* if this list is empty
* @since 1.6
*/
public E peekLast() {
if (size==0)
return null;
return getLast();
}
/**
* Retrieves and removes the first element of this list,
* or returns null if this list is empty.
*
* @return the first element of this list, or null if
* this list is empty
* @since 1.6
*/
public E pollFirst() {
if (size==0)
return null;
return removeFirst();
}
/**
* Retrieves and removes the last element of this list,
* or returns null if this list is empty.
*
* @return the last element of this list, or null if
* this list is empty
* @since 1.6
*/
public E pollLast() {
if (size==0)
return null;
return removeLast();
}
/**
* Pushes an element onto the stack represented by this list. In other
* words, inserts the element at the front of this list.
*
* This method is equivalent to {@link #addFirst}.
*
* @param e the element to push
* @since 1.6
*/
public void push(E e) {
addFirst(e);
}
/**
* Pops an element from the stack represented by this list. In other
* words, removes and returns the first element of this list.
*
*
This method is equivalent to {@link #removeFirst()}.
*
* @return the element at the front of this list (which is the top
* of the stack represented by this list)
* @throws NoSuchElementException if this list is empty
* @since 1.6
*/
public E pop() {
return removeFirst();
}
/**
* Removes the first occurrence of the specified element in this
* list (when traversing the list from head to tail). If the list
* does not contain the element, it is unchanged.
*
* @param o element to be removed from this list, if present
* @return true if the list contained the specified element
* @since 1.6
*/
public boolean removeFirstOccurrence(Object o) {
return remove(o);
}
/**
* Removes the last occurrence of the specified element in this
* list (when traversing the list from head to tail). If the list
* does not contain the element, it is unchanged.
*
* @param o element to be removed from this list, if present
* @return true if the list contained the specified element
* @since 1.6
*/
public boolean removeLastOccurrence(Object o) {
if (o==null) {
for (Entry e = header.previous; e != header; e = e.previous) {
if (e.element==null) {
remove(e);
return true;
}
}
} else {
for (Entry e = header.previous; e != header; e = e.previous) {
if (o.equals(e.element)) {
remove(e);
return true;
}
}
}
return false;
}
/**
* Returns a list-iterator of the elements in this list (in proper
* sequence), starting at the specified position in the list.
* Obeys the general contract of List.listIterator(int).
*
* The list-iterator is fail-fast: if the list is structurally
* modified at any time after the Iterator is created, in any way except
* through the list-iterator's own remove or add
* methods, the list-iterator will throw a
* ConcurrentModificationException. Thus, in the face of
* concurrent modification, the iterator fails quickly and cleanly, rather
* than risking arbitrary, non-deterministic behavior at an undetermined
* time in the future.
*
* @param index index of the first element to be returned from the
* list-iterator (by a call to next)
* @return a ListIterator of the elements in this list (in proper
* sequence), starting at the specified position in the list
* @throws IndexOutOfBoundsException {@inheritDoc}
* @see List#listIterator(int)
*/
public ListIterator listIterator(int index) {
return new ListItr(index);
}
private class ListItr implements ListIterator {
private Entry lastReturned = header;
private Entry next;
private int nextIndex;
private int expectedModCount = modCount;
ListItr(int index) {
if (index < 0 || index > size)
throw new IndexOutOfBoundsException();
if (index < (size >> 1)) {
next = header.next;
for (nextIndex=0; nextIndexindex; nextIndex--)
next = next.previous;
}
}
public boolean hasNext() {
return nextIndex != size;
}
public E next() {
checkForComodification();
if (nextIndex == size)
throw new NoSuchElementException();
lastReturned = next;
next = next.next;
nextIndex++;
return lastReturned.element;
}
public boolean hasPrevious() {
return nextIndex != 0;
}
public E previous() {
if (nextIndex == 0)
throw new NoSuchElementException();
lastReturned = next = next.previous;
nextIndex--;
checkForComodification();
return lastReturned.element;
}
public int nextIndex() {
return nextIndex;
}
public int previousIndex() {
return nextIndex-1;
}
public void remove() {
checkForComodification();
Entry lastNext = lastReturned.next;
try {
LinkedList.this.remove(lastReturned);
} catch (NoSuchElementException e) {
throw new IllegalStateException();
}
if (next==lastReturned)
next = lastNext;
else
nextIndex--;
lastReturned = header;
expectedModCount++;
}
public void set(E e) {
if (lastReturned == header)
throw new IllegalStateException();
checkForComodification();
lastReturned.element = e;
}
public void add(E e) {
checkForComodification();
lastReturned = header;
addBefore(e, next);
nextIndex++;
expectedModCount++;
}
final void checkForComodification() {
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
}
}
private static class Entry {
E element;
Entry next;
Entry previous;
Entry(E element, Entry next, Entry