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/* |
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* %W% %E% |
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* |
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* Copyright 2006 Sun Microsystems, Inc. All rights reserved. |
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* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
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*/ |
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|
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package java.util; |
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|
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/** |
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* This class provides a skeletal implementation of the <tt>List</tt> |
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* interface to minimize the effort required to implement this interface |
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* backed by a "random access" data store (such as an array). For sequential |
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* access data (such as a linked list), <tt>AbstractSequentialList</tt> should |
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* be used in preference to this class.<p> |
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* |
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* To implement an unmodifiable list, the programmer needs only to extend this |
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* class and provide implementations for the <tt>get(int index)</tt> and |
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* <tt>size()</tt> methods.<p> |
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* |
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* To implement a modifiable list, the programmer must additionally override |
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* the <tt>set(int index, Object element)</tt> method (which otherwise throws |
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* an <tt>UnsupportedOperationException</tt>. If the list is variable-size |
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* the programmer must additionally override the <tt>add(int index, Object |
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* element)</tt> and <tt>remove(int index)</tt> methods.<p> |
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* |
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* The programmer should generally provide a void (no argument) and collection |
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* constructor, as per the recommendation in the <tt>Collection</tt> interface |
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* specification.<p> |
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* |
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* Unlike the other abstract collection implementations, the programmer does |
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* <i>not</i> have to provide an iterator implementation; the iterator and |
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* list iterator are implemented by this class, on top of the "random access" |
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* methods: <tt>get(int index)</tt>, <tt>set(int index, E element)</tt>, |
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* <tt>add(int index, E element)</tt> and <tt>remove(int index)</tt>.<p> |
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* |
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* The documentation for each non-abstract methods in this class describes its |
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* implementation in detail. Each of these methods may be overridden if the |
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* collection being implemented admits a more efficient implementation.<p> |
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* |
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* This class is a member of the |
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* <a href="{@docRoot}/../guide/collections/index.html"> |
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* Java Collections Framework</a>. |
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* |
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* @author Josh Bloch |
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* @author Neal Gafter |
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* @version %I%, %G% |
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* @see Collection |
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* @see List |
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* @see AbstractSequentialList |
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* @see AbstractCollection |
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* @since 1.2 |
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*/ |
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|
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public abstract class AbstractList<E> extends AbstractCollection<E> implements List<E> { |
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/** |
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* Sole constructor. (For invocation by subclass constructors, typically |
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* implicit.) |
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*/ |
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protected AbstractList() { |
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} |
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|
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/** |
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* Appends the specified element to the end of this list (optional |
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* operation). |
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* |
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* <p>Lists that support this operation may place limitations on what |
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* elements may be added to this list. In particular, some |
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* lists will refuse to add null elements, and others will impose |
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* restrictions on the type of elements that may be added. List |
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* classes should clearly specify in their documentation any restrictions |
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* on what elements may be added. |
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* |
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* <p>This implementation calls <tt>add(size(), e)</tt>. |
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* |
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* <p>Note that this implementation throws an |
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* <tt>UnsupportedOperationException</tt> unless <tt>add(int, Object)</tt> |
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* is overridden. |
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* |
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* @param e element to be appended to this list |
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* @return <tt>true</tt> (as specified by {@link Collection#add}) |
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* @throws UnsupportedOperationException if the <tt>add</tt> operation |
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* is not supported by this list |
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* @throws ClassCastException if the class of the specified element |
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* prevents it from being added to this list |
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* @throws NullPointerException if the specified element is null and this |
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* list does not permit null elements |
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* @throws IllegalArgumentException if some property of this element |
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* prevents it from being added to this list |
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*/ |
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public boolean add(E e) { |
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add(size(), e); |
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return true; |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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abstract public E get(int index); |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation always throws an |
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* <tt>UnsupportedOperationException</tt>. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws IllegalArgumentException {@inheritDoc} |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public E set(int index, E element) { |
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throw new UnsupportedOperationException(); |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation always throws an |
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* <tt>UnsupportedOperationException</tt>. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws IllegalArgumentException {@inheritDoc} |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public void add(int index, E element) { |
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throw new UnsupportedOperationException(); |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation always throws an |
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* <tt>UnsupportedOperationException</tt>. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public E remove(int index) { |
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throw new UnsupportedOperationException(); |
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} |
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|
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|
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// Search Operations |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation first gets a list iterator (with |
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* <tt>listIterator()</tt>). Then, it iterates over the list until the |
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* specified element is found or the end of the list is reached. |
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* |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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*/ |
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public int indexOf(Object o) { |
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ListIterator<E> e = listIterator(); |
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if (o==null) { |
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while (e.hasNext()) |
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if (e.next()==null) |
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return e.previousIndex(); |
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} else { |
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while (e.hasNext()) |
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if (o.equals(e.next())) |
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return e.previousIndex(); |
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} |
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return -1; |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation first gets a list iterator that points to the end |
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* of the list (with <tt>listIterator(size())</tt>). Then, it iterates |
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* backwards over the list until the specified element is found, or the |
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* beginning of the list is reached. |
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* |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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*/ |
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public int lastIndexOf(Object o) { |
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ListIterator<E> e = listIterator(size()); |
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if (o==null) { |
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while (e.hasPrevious()) |
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if (e.previous()==null) |
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return e.nextIndex(); |
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} else { |
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while (e.hasPrevious()) |
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if (o.equals(e.previous())) |
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return e.nextIndex(); |
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} |
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return -1; |
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} |
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|
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|
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// Bulk Operations |
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|
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/** |
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* Removes all of the elements from this list (optional operation). |
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* The list will be empty after this call returns. |
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* |
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* <p>This implementation calls <tt>removeRange(0, size())</tt>. |
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* |
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* <p>Note that this implementation throws an |
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* <tt>UnsupportedOperationException</tt> unless <tt>remove(int |
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* index)</tt> or <tt>removeRange(int fromIndex, int toIndex)</tt> is |
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* overridden. |
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* |
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* @throws UnsupportedOperationException if the <tt>clear</tt> operation |
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* is not supported by this list |
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*/ |
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public void clear() { |
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removeRange(0, size()); |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation gets an iterator over the specified collection and |
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* iterates over it, inserting the elements obtained from the iterator |
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* into this list at the appropriate position, one at a time, using |
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* <tt>add(int, Object)</tt>. Many implementations will override this |
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* method for efficiency. |
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* |
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* <p>Note that this implementation throws an |
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* <tt>UnsupportedOperationException</tt> unless <tt>add(int, Object)</tt> |
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* is overridden. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws IllegalArgumentException {@inheritDoc} |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public boolean addAll(int index, Collection<? extends E> c) { |
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boolean modified = false; |
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Iterator<? extends E> e = c.iterator(); |
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while (e.hasNext()) { |
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add(index++, e.next()); |
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modified = true; |
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} |
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return modified; |
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} |
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|
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|
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// Iterators |
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|
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/** |
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* Returns an iterator over the elements in this list in proper |
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* sequence. <p> |
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* |
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* This implementation returns a straightforward implementation of the |
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* iterator interface, relying on the backing list's <tt>size()</tt>, |
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* <tt>get(int)</tt>, and <tt>remove(int)</tt> methods.<p> |
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* |
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* Note that the iterator returned by this method will throw an |
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* <tt>UnsupportedOperationException</tt> in response to its |
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* <tt>remove</tt> method unless the list's <tt>remove(int)</tt> method is |
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* overridden.<p> |
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* |
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* This implementation can be made to throw runtime exceptions in the face |
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* of concurrent modification, as described in the specification for the |
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* (protected) <tt>modCount</tt> field. |
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* |
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* @return an iterator over the elements in this list in proper sequence |
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* |
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* @see #modCount |
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*/ |
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public Iterator<E> iterator() { |
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return new Itr(); |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation returns <tt>listIterator(0)</tt>. |
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* |
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* @see #listIterator(int) |
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*/ |
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public ListIterator<E> listIterator() { |
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return listIterator(0); |
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} |
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|
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/** |
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* {@inheritDoc} |
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* |
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* <p>This implementation returns a straightforward implementation of the |
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* <tt>ListIterator</tt> interface that extends the implementation of the |
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* <tt>Iterator</tt> interface returned by the <tt>iterator()</tt> method. |
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* The <tt>ListIterator</tt> implementation relies on the backing list's |
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* <tt>get(int)</tt>, <tt>set(int, Object)</tt>, <tt>add(int, Object)</tt> |
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* and <tt>remove(int)</tt> methods. |
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* |
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* <p>Note that the list iterator returned by this implementation will |
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* throw an <tt>UnsupportedOperationException</tt> in response to its |
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* <tt>remove</tt>, <tt>set</tt> and <tt>add</tt> methods unless the |
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* list's <tt>remove(int)</tt>, <tt>set(int, Object)</tt>, and |
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* <tt>add(int, Object)</tt> methods are overridden. |
304 |
* |
305 |
* <p>This implementation can be made to throw runtime exceptions in the |
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* face of concurrent modification, as described in the specification for |
307 |
* the (protected) <tt>modCount</tt> field. |
308 |
* |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
310 |
* |
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* @see #modCount |
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*/ |
313 |
public ListIterator<E> listIterator(final int index) { |
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if (index<0 || index>size()) |
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throw new IndexOutOfBoundsException("Index: "+index); |
316 |
|
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return new ListItr(index); |
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} |
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|
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private class Itr implements Iterator<E> { |
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/** |
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* Index of element to be returned by subsequent call to next. |
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*/ |
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int cursor = 0; |
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|
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/** |
327 |
* Index of element returned by most recent call to next or |
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* previous. Reset to -1 if this element is deleted by a call |
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* to remove. |
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*/ |
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int lastRet = -1; |
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|
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/** |
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* The modCount value that the iterator believes that the backing |
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* List should have. If this expectation is violated, the iterator |
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* has detected concurrent modification. |
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*/ |
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int expectedModCount = modCount; |
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|
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public boolean hasNext() { |
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return cursor != size(); |
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} |
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|
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public E next() { |
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try { |
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int i = cursor; |
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E next = get(i); |
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lastRet = i; |
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cursor = i + 1; |
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return next; |
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} catch (IndexOutOfBoundsException ex) { |
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throw new NoSuchElementException(); |
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} finally { |
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if (expectedModCount != modCount) |
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throw new ConcurrentModificationException(); |
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} |
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} |
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|
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public void remove() { |
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if (lastRet == -1) |
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throw new IllegalStateException(); |
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if (expectedModCount != modCount) |
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throw new ConcurrentModificationException(); |
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try { |
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AbstractList.this.remove(lastRet); |
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if (lastRet < cursor) |
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cursor--; |
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lastRet = -1; |
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expectedModCount = modCount; |
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} catch (IndexOutOfBoundsException e) { |
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throw new ConcurrentModificationException(); |
372 |
} |
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} |
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} |
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|
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private class ListItr extends Itr implements ListIterator<E> { |
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ListItr(int index) { |
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cursor = index; |
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} |
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|
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public boolean hasPrevious() { |
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return cursor != 0; |
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} |
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|
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public int nextIndex() { |
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return cursor; |
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} |
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|
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public int previousIndex() { |
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return cursor - 1; |
391 |
} |
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|
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public E previous() { |
394 |
try { |
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int i = cursor - 1; |
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E prev = get(i); |
397 |
lastRet = i; |
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cursor = i; |
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return prev; |
400 |
} catch (IndexOutOfBoundsException ex) { |
401 |
throw new NoSuchElementException(); |
402 |
} finally { |
403 |
if (expectedModCount != modCount) |
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throw new ConcurrentModificationException(); |
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} |
406 |
} |
407 |
|
408 |
public void set(E e) { |
409 |
if (lastRet == -1) |
410 |
throw new IllegalStateException(); |
411 |
if (expectedModCount != modCount) |
412 |
throw new ConcurrentModificationException(); |
413 |
try { |
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AbstractList.this.set(lastRet, e); |
415 |
expectedModCount = modCount; |
416 |
} catch (IndexOutOfBoundsException ex) { |
417 |
throw new ConcurrentModificationException(); |
418 |
} |
419 |
} |
420 |
|
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public void add(E e) { |
422 |
if (expectedModCount != modCount) |
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throw new ConcurrentModificationException(); |
424 |
try { |
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int i = cursor; |
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AbstractList.this.add(i, e); |
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cursor = i + 1; |
428 |
lastRet = -1; |
429 |
expectedModCount = modCount; |
430 |
} catch (IndexOutOfBoundsException ex) { |
431 |
throw new ConcurrentModificationException(); |
432 |
} |
433 |
} |
434 |
} |
435 |
|
436 |
/** |
437 |
* {@inheritDoc} |
438 |
* |
439 |
* <p>This implementation returns a list that subclasses |
440 |
* <tt>AbstractList</tt>. The subclass stores, in private fields, the |
441 |
* offset of the subList within the backing list, the size of the subList |
442 |
* (which can change over its lifetime), and the expected |
443 |
* <tt>modCount</tt> value of the backing list. There are two variants |
444 |
* of the subclass, one of which implements <tt>RandomAccess</tt>. |
445 |
* If this list implements <tt>RandomAccess</tt> the returned list will |
446 |
* be an instance of the subclass that implements <tt>RandomAccess</tt>. |
447 |
* |
448 |
* <p>The subclass's <tt>set(int, Object)</tt>, <tt>get(int)</tt>, |
449 |
* <tt>add(int, Object)</tt>, <tt>remove(int)</tt>, <tt>addAll(int, |
450 |
* Collection)</tt> and <tt>removeRange(int, int)</tt> methods all |
451 |
* delegate to the corresponding methods on the backing abstract list, |
452 |
* after bounds-checking the index and adjusting for the offset. The |
453 |
* <tt>addAll(Collection c)</tt> method merely returns <tt>addAll(size, |
454 |
* c)</tt>. |
455 |
* |
456 |
* <p>The <tt>listIterator(int)</tt> method returns a "wrapper object" |
457 |
* over a list iterator on the backing list, which is created with the |
458 |
* corresponding method on the backing list. The <tt>iterator</tt> method |
459 |
* merely returns <tt>listIterator()</tt>, and the <tt>size</tt> method |
460 |
* merely returns the subclass's <tt>size</tt> field. |
461 |
* |
462 |
* <p>All methods first check to see if the actual <tt>modCount</tt> of |
463 |
* the backing list is equal to its expected value, and throw a |
464 |
* <tt>ConcurrentModificationException</tt> if it is not. |
465 |
* |
466 |
* @throws IndexOutOfBoundsException endpoint index value out of range |
467 |
* <tt>(fromIndex < 0 || toIndex > size)</tt> |
468 |
* @throws IllegalArgumentException if the endpoint indices are out of order |
469 |
* <tt>(fromIndex > toIndex)</tt> |
470 |
*/ |
471 |
public List<E> subList(int fromIndex, int toIndex) { |
472 |
return (this instanceof RandomAccess ? |
473 |
new RandomAccessSubList<E>(this, fromIndex, toIndex) : |
474 |
new SubList<E>(this, fromIndex, toIndex)); |
475 |
} |
476 |
|
477 |
// Comparison and hashing |
478 |
|
479 |
/** |
480 |
* Compares the specified object with this list for equality. Returns |
481 |
* <tt>true</tt> if and only if the specified object is also a list, both |
482 |
* lists have the same size, and all corresponding pairs of elements in |
483 |
* the two lists are <i>equal</i>. (Two elements <tt>e1</tt> and |
484 |
* <tt>e2</tt> are <i>equal</i> if <tt>(e1==null ? e2==null : |
485 |
* e1.equals(e2))</tt>.) In other words, two lists are defined to be |
486 |
* equal if they contain the same elements in the same order.<p> |
487 |
* |
488 |
* This implementation first checks if the specified object is this |
489 |
* list. If so, it returns <tt>true</tt>; if not, it checks if the |
490 |
* specified object is a list. If not, it returns <tt>false</tt>; if so, |
491 |
* it iterates over both lists, comparing corresponding pairs of elements. |
492 |
* If any comparison returns <tt>false</tt>, this method returns |
493 |
* <tt>false</tt>. If either iterator runs out of elements before the |
494 |
* other it returns <tt>false</tt> (as the lists are of unequal length); |
495 |
* otherwise it returns <tt>true</tt> when the iterations complete. |
496 |
* |
497 |
* @param o the object to be compared for equality with this list |
498 |
* @return <tt>true</tt> if the specified object is equal to this list |
499 |
*/ |
500 |
public boolean equals(Object o) { |
501 |
if (o == this) |
502 |
return true; |
503 |
if (!(o instanceof List)) |
504 |
return false; |
505 |
|
506 |
ListIterator<E> e1 = listIterator(); |
507 |
ListIterator e2 = ((List) o).listIterator(); |
508 |
while(e1.hasNext() && e2.hasNext()) { |
509 |
E o1 = e1.next(); |
510 |
Object o2 = e2.next(); |
511 |
if (!(o1==null ? o2==null : o1.equals(o2))) |
512 |
return false; |
513 |
} |
514 |
return !(e1.hasNext() || e2.hasNext()); |
515 |
} |
516 |
|
517 |
/** |
518 |
* Returns the hash code value for this list. <p> |
519 |
* |
520 |
* This implementation uses exactly the code that is used to define the |
521 |
* list hash function in the documentation for the {@link List#hashCode} |
522 |
* method. |
523 |
* |
524 |
* @return the hash code value for this list |
525 |
*/ |
526 |
public int hashCode() { |
527 |
int hashCode = 1; |
528 |
Iterator<E> i = iterator(); |
529 |
while (i.hasNext()) { |
530 |
E obj = i.next(); |
531 |
hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); |
532 |
} |
533 |
return hashCode; |
534 |
} |
535 |
|
536 |
/** |
537 |
* Removes from this list all of the elements whose index is between |
538 |
* <tt>fromIndex</tt>, inclusive, and <tt>toIndex</tt>, exclusive. |
539 |
* Shifts any succeeding elements to the left (reduces their index). |
540 |
* This call shortens the ArrayList by <tt>(toIndex - fromIndex)</tt> |
541 |
* elements. (If <tt>toIndex==fromIndex</tt>, this operation has no |
542 |
* effect.)<p> |
543 |
* |
544 |
* This method is called by the <tt>clear</tt> operation on this list |
545 |
* and its subLists. Overriding this method to take advantage of |
546 |
* the internals of the list implementation can <i>substantially</i> |
547 |
* improve the performance of the <tt>clear</tt> operation on this list |
548 |
* and its subLists.<p> |
549 |
* |
550 |
* This implementation gets a list iterator positioned before |
551 |
* <tt>fromIndex</tt>, and repeatedly calls <tt>ListIterator.next</tt> |
552 |
* followed by <tt>ListIterator.remove</tt> until the entire range has |
553 |
* been removed. <b>Note: if <tt>ListIterator.remove</tt> requires linear |
554 |
* time, this implementation requires quadratic time.</b> |
555 |
* |
556 |
* @param fromIndex index of first element to be removed |
557 |
* @param toIndex index after last element to be removed |
558 |
*/ |
559 |
protected void removeRange(int fromIndex, int toIndex) { |
560 |
ListIterator<E> it = listIterator(fromIndex); |
561 |
for (int i=0, n=toIndex-fromIndex; i<n; i++) { |
562 |
it.next(); |
563 |
it.remove(); |
564 |
} |
565 |
} |
566 |
|
567 |
/** |
568 |
* The number of times this list has been <i>structurally modified</i>. |
569 |
* Structural modifications are those that change the size of the |
570 |
* list, or otherwise perturb it in such a fashion that iterations in |
571 |
* progress may yield incorrect results.<p> |
572 |
* |
573 |
* This field is used by the iterator and list iterator implementation |
574 |
* returned by the <tt>iterator</tt> and <tt>listIterator</tt> methods. |
575 |
* If the value of this field changes unexpectedly, the iterator (or list |
576 |
* iterator) will throw a <tt>ConcurrentModificationException</tt> in |
577 |
* response to the <tt>next</tt>, <tt>remove</tt>, <tt>previous</tt>, |
578 |
* <tt>set</tt> or <tt>add</tt> operations. This provides |
579 |
* <i>fail-fast</i> behavior, rather than non-deterministic behavior in |
580 |
* the face of concurrent modification during iteration.<p> |
581 |
* |
582 |
* <b>Use of this field by subclasses is optional.</b> If a subclass |
583 |
* wishes to provide fail-fast iterators (and list iterators), then it |
584 |
* merely has to increment this field in its <tt>add(int, Object)</tt> and |
585 |
* <tt>remove(int)</tt> methods (and any other methods that it overrides |
586 |
* that result in structural modifications to the list). A single call to |
587 |
* <tt>add(int, Object)</tt> or <tt>remove(int)</tt> must add no more than |
588 |
* one to this field, or the iterators (and list iterators) will throw |
589 |
* bogus <tt>ConcurrentModificationExceptions</tt>. If an implementation |
590 |
* does not wish to provide fail-fast iterators, this field may be |
591 |
* ignored. |
592 |
*/ |
593 |
protected transient int modCount = 0; |
594 |
} |
595 |
|
596 |
class SubList<E> extends AbstractList<E> { |
597 |
private AbstractList<E> l; |
598 |
private int offset; |
599 |
private int size; |
600 |
private int expectedModCount; |
601 |
|
602 |
SubList(AbstractList<E> list, int fromIndex, int toIndex) { |
603 |
if (fromIndex < 0) |
604 |
throw new IndexOutOfBoundsException("fromIndex = " + fromIndex); |
605 |
if (toIndex > list.size()) |
606 |
throw new IndexOutOfBoundsException("toIndex = " + toIndex); |
607 |
if (fromIndex > toIndex) |
608 |
throw new IllegalArgumentException("fromIndex(" + fromIndex + |
609 |
") > toIndex(" + toIndex + ")"); |
610 |
l = list; |
611 |
offset = fromIndex; |
612 |
size = toIndex - fromIndex; |
613 |
expectedModCount = l.modCount; |
614 |
} |
615 |
|
616 |
public E set(int index, E element) { |
617 |
rangeCheck(index); |
618 |
checkForComodification(); |
619 |
return l.set(index+offset, element); |
620 |
} |
621 |
|
622 |
public E get(int index) { |
623 |
rangeCheck(index); |
624 |
checkForComodification(); |
625 |
return l.get(index+offset); |
626 |
} |
627 |
|
628 |
public int size() { |
629 |
checkForComodification(); |
630 |
return size; |
631 |
} |
632 |
|
633 |
public void add(int index, E element) { |
634 |
if (index<0 || index>size) |
635 |
throw new IndexOutOfBoundsException(); |
636 |
checkForComodification(); |
637 |
l.add(index+offset, element); |
638 |
expectedModCount = l.modCount; |
639 |
size++; |
640 |
modCount++; |
641 |
} |
642 |
|
643 |
public E remove(int index) { |
644 |
rangeCheck(index); |
645 |
checkForComodification(); |
646 |
E result = l.remove(index+offset); |
647 |
expectedModCount = l.modCount; |
648 |
size--; |
649 |
modCount++; |
650 |
return result; |
651 |
} |
652 |
|
653 |
protected void removeRange(int fromIndex, int toIndex) { |
654 |
checkForComodification(); |
655 |
l.removeRange(fromIndex+offset, toIndex+offset); |
656 |
expectedModCount = l.modCount; |
657 |
size -= (toIndex-fromIndex); |
658 |
modCount++; |
659 |
} |
660 |
|
661 |
public boolean addAll(Collection<? extends E> c) { |
662 |
return addAll(size, c); |
663 |
} |
664 |
|
665 |
public boolean addAll(int index, Collection<? extends E> c) { |
666 |
if (index<0 || index>size) |
667 |
throw new IndexOutOfBoundsException( |
668 |
"Index: "+index+", Size: "+size); |
669 |
int cSize = c.size(); |
670 |
if (cSize==0) |
671 |
return false; |
672 |
|
673 |
checkForComodification(); |
674 |
l.addAll(offset+index, c); |
675 |
expectedModCount = l.modCount; |
676 |
size += cSize; |
677 |
modCount++; |
678 |
return true; |
679 |
} |
680 |
|
681 |
public Iterator<E> iterator() { |
682 |
return listIterator(); |
683 |
} |
684 |
|
685 |
public ListIterator<E> listIterator(final int index) { |
686 |
checkForComodification(); |
687 |
if (index<0 || index>size) |
688 |
throw new IndexOutOfBoundsException( |
689 |
"Index: "+index+", Size: "+size); |
690 |
|
691 |
return new ListIterator<E>() { |
692 |
private ListIterator<E> i = l.listIterator(index+offset); |
693 |
|
694 |
public boolean hasNext() { |
695 |
return nextIndex() < size; |
696 |
} |
697 |
|
698 |
public E next() { |
699 |
if (hasNext()) |
700 |
return i.next(); |
701 |
else |
702 |
throw new NoSuchElementException(); |
703 |
} |
704 |
|
705 |
public boolean hasPrevious() { |
706 |
return previousIndex() >= 0; |
707 |
} |
708 |
|
709 |
public E previous() { |
710 |
if (hasPrevious()) |
711 |
return i.previous(); |
712 |
else |
713 |
throw new NoSuchElementException(); |
714 |
} |
715 |
|
716 |
public int nextIndex() { |
717 |
return i.nextIndex() - offset; |
718 |
} |
719 |
|
720 |
public int previousIndex() { |
721 |
return i.previousIndex() - offset; |
722 |
} |
723 |
|
724 |
public void remove() { |
725 |
i.remove(); |
726 |
expectedModCount = l.modCount; |
727 |
size--; |
728 |
modCount++; |
729 |
} |
730 |
|
731 |
public void set(E e) { |
732 |
i.set(e); |
733 |
} |
734 |
|
735 |
public void add(E e) { |
736 |
i.add(e); |
737 |
expectedModCount = l.modCount; |
738 |
size++; |
739 |
modCount++; |
740 |
} |
741 |
}; |
742 |
} |
743 |
|
744 |
public List<E> subList(int fromIndex, int toIndex) { |
745 |
return new SubList<E>(this, fromIndex, toIndex); |
746 |
} |
747 |
|
748 |
private void rangeCheck(int index) { |
749 |
if (index<0 || index>=size) |
750 |
throw new IndexOutOfBoundsException("Index: "+index+ |
751 |
",Size: "+size); |
752 |
} |
753 |
|
754 |
private void checkForComodification() { |
755 |
if (l.modCount != expectedModCount) |
756 |
throw new ConcurrentModificationException(); |
757 |
} |
758 |
} |
759 |
|
760 |
class RandomAccessSubList<E> extends SubList<E> implements RandomAccess { |
761 |
RandomAccessSubList(AbstractList<E> list, int fromIndex, int toIndex) { |
762 |
super(list, fromIndex, toIndex); |
763 |
} |
764 |
|
765 |
public List<E> subList(int fromIndex, int toIndex) { |
766 |
return new RandomAccessSubList<E>(this, fromIndex, toIndex); |
767 |
} |
768 |
} |