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/* |
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* %W% %E% |
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* |
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* Copyright 2005 Sun Microsystems, Inc. All rights reserved. |
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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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* list. Operations that index into the list will traverse the list from |
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* the beginning or the end, whichever is closer to the specified index.<p> |
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* |
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* <b>Note that this implementation is not synchronized.</b> If multiple |
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* threads access a list concurrently, and at least one of the threads |
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* modifies the list structurally, it <i>must</i> be synchronized |
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* externally. (A structural modification is any operation that adds or |
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* deletes one or more elements; merely setting the value of an element is not |
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* a structural modification.) This is typically accomplished by |
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* synchronizing on some object that naturally encapsulates the list. If no |
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* such object exists, the list should be "wrapped" using the |
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* Collections.synchronizedList method. This is best done at creation time, |
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* to prevent accidental unsynchronized access to the list: <pre> |
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* List list = Collections.synchronizedList(new LinkedList(...)); |
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* </pre> |
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* <p><strong>Note that this implementation is not synchronized.</strong> |
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* If multiple threads access a linked list concurrently, and at least |
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* one of the threads modifies the list structurally, it <i>must</i> be |
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* synchronized externally. (A structural modification is any operation |
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* that adds or deletes one or more elements; merely setting the value of |
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* an element is not a structural modification.) This is typically |
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* accomplished by synchronizing on some object that naturally |
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* encapsulates the list. |
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* |
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* If no such object exists, the list should be "wrapped" using the |
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* {@link Collections#synchronizedList Collections.synchronizedList} |
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* method. This is best done at creation time, to prevent accidental |
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* unsynchronized access to the list:<pre> |
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* List list = Collections.synchronizedList(new LinkedList(...));</pre> |
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* |
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* <p>The iterators returned by this class's <tt>iterator</tt> and |
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* <tt>listIterator</tt> methods are <i>fail-fast</i>: if the list is |
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* should be used only to detect bugs.</i> |
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* |
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* <p>This class is a member of the |
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* <a href="{@docRoot}/../guide/collections/index.html"> |
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* <a href="{@docRoot}/../technotes/guides/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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* @see List |
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* @see ArrayList |
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* @see Vector |
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* @see Collections#synchronizedList(List) |
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* @since 1.2 |
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* @param <E> the type of elements held in this collection |
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*/ |
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* collection, in the order they are returned by the collection's |
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* iterator. |
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* |
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* @param c the collection whose elements are to be placed into this list. |
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* @throws NullPointerException if the specified collection is null. |
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* @param c the collection whose elements are to be placed into this list |
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* @throws NullPointerException if the specified collection is null |
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*/ |
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public LinkedList(Collection<? extends E> c) { |
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this(); |
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addAll(c); |
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} |
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public LinkedList(Collection<? extends E> c) { |
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this(); |
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addAll(c); |
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} |
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|
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/** |
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* Returns the first element in this list. |
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* |
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* @return the first element in this list. |
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* @throws NoSuchElementException if this list is empty. |
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* @return the first element in this list |
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* @throws NoSuchElementException if this list is empty |
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*/ |
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public E getFirst() { |
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if (size==0) |
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/** |
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* Returns the last element in this list. |
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* |
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* @return the last element in this list. |
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* @throws NoSuchElementException if this list is empty. |
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* @return the last element in this list |
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* @throws NoSuchElementException if this list is empty |
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*/ |
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public E getLast() { |
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if (size==0) |
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/** |
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* Removes and returns the first element from this list. |
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* |
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* @return the first element from this list. |
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* @throws NoSuchElementException if this list is empty. |
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* @return the first element from this list |
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* @throws NoSuchElementException if this list is empty |
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*/ |
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public E removeFirst() { |
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return remove(header.next); |
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/** |
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* Removes and returns the last element from this list. |
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* |
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* @return the last element from this list. |
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* @throws NoSuchElementException if this list is empty. |
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* @return the last element from this list |
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* @throws NoSuchElementException if this list is empty |
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*/ |
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public E removeLast() { |
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return remove(header.previous); |
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} |
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|
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/** |
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* Inserts the given element at the beginning of this list. |
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* Inserts the specified element at the beginning of this list. |
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* |
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* @param e the element to be inserted at the beginning of this list. |
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* @param e the element to add |
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*/ |
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public void addFirst(E e) { |
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addBefore(e, header.next); |
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} |
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|
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/** |
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* Appends the given element to the end of this list. (Identical in |
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* function to the <tt>add</tt> method; included only for consistency.) |
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* Appends the specified element to the end of this list. |
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* |
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* <p>This method is equivalent to {@link #add}. |
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* |
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* @param e the element to be inserted at the end of this list. |
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* @param e the element to add |
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*/ |
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public void addLast(E e) { |
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addBefore(e, header); |
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/** |
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* Returns <tt>true</tt> if this list contains the specified element. |
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* More formally, returns <tt>true</tt> if and only if this list contains |
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* at least one element <tt>e</tt> such that <tt>(o==null ? e==null |
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* : o.equals(e))</tt>. |
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* at least one element <tt>e</tt> such that |
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* <tt>(o==null ? e==null : o.equals(e))</tt>. |
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* |
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* @param o element whose presence in this list is to be tested. |
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* @return <tt>true</tt> if this list contains the specified element. |
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* @param o element whose presence in this list is to be tested |
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* @return <tt>true</tt> if this list contains the specified element |
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*/ |
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public boolean contains(Object o) { |
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return indexOf(o) != -1; |
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/** |
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* Returns the number of elements in this list. |
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* |
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* @return the number of elements in this list. |
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* @return the number of elements in this list |
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*/ |
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public int size() { |
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return size; |
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/** |
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* Appends the specified element to the end of this list. |
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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 per the general contract of |
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* <tt>Collection.add</tt>). |
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* <p>This method is equivalent to {@link #addLast}. |
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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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*/ |
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public boolean add(E e) { |
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addBefore(e, header); |
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} |
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|
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/** |
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* Removes the first occurrence of the specified element in this list. If |
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* the list does not contain the element, it is unchanged. More formally, |
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* removes the element with the lowest index <tt>i</tt> such that |
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* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> (if such an |
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* element exists). |
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* Removes the first occurrence of the specified element from this list, |
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* if it is present. If this list does not contain the element, it is |
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* unchanged. More formally, removes the element with the lowest index |
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* <tt>i</tt> such that |
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* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> |
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* (if such an element exists). Returns <tt>true</tt> if this list |
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* contained the specified element (or equivalently, if this list |
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* changed as a result of the call). |
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* |
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* @param o element to be removed from this list, if present. |
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* @return <tt>true</tt> if the list contained the specified element. |
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* @param o element to be removed from this list, if present |
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* @return <tt>true</tt> if this list contained the specified element |
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*/ |
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public boolean remove(Object o) { |
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if (o==null) { |
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* this list, in the order that they are returned by the specified |
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* collection's iterator. The behavior of this operation is undefined if |
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* the specified collection is modified while the operation is in |
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* progress. (This implies that the behavior of this call is undefined if |
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* the specified Collection is this list, and this list is nonempty.) |
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* progress. (Note that this will occur if the specified collection is |
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* this list, and it's nonempty.) |
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* |
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* @param c the elements to be inserted into this list. |
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* @return <tt>true</tt> if this list changed as a result of the call. |
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* @throws NullPointerException if the specified collection is null. |
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* @param c collection containing elements to be added to this list |
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* @return <tt>true</tt> if this list changed as a result of the call |
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* @throws NullPointerException if the specified collection is null |
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*/ |
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public boolean addAll(Collection<? extends E> c) { |
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return addAll(size, c); |
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* in the list in the order that they are returned by the |
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* specified collection's iterator. |
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* |
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* @param index index at which to insert first element |
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* from the specified collection. |
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* @param c elements to be inserted into this list. |
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* @return <tt>true</tt> if this list changed as a result of the call. |
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* @throws IndexOutOfBoundsException if the index is out of range |
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* (<tt>index < 0 || index > size()</tt>). |
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* @throws NullPointerException if the specified collection is null. |
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* @param index index at which to insert the first element |
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* from the specified collection |
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* @param c collection containing elements to be added to this list |
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* @return <tt>true</tt> if this list changed as a result of the call |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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* @throws NullPointerException if the specified collection is null |
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*/ |
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public boolean addAll(int index, Collection<? extends E> c) { |
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if (index < 0 || index > size) |
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/** |
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* Returns the element at the specified position in this list. |
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* |
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* @param index index of element to return. |
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* @return the element at the specified position in this list. |
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* |
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* @throws IndexOutOfBoundsException if the index is out of range |
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* (<tt>index < 0 || index > size()</tt>). |
310 |
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* @param index index of the element to return |
311 |
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* @return the element at the specified position in this list |
312 |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public E get(int index) { |
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return entry(index).element; |
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* Replaces the element at the specified position in this list with the |
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* specified element. |
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* |
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* @param index index of element to replace. |
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* @param element element to be stored at the specified position. |
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* @return the element previously at the specified position. |
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* @throws IndexOutOfBoundsException if the index is out of range |
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* (<tt>index < 0 || index > size()</tt>). |
322 |
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* @param index index of the element to replace |
323 |
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* @param element element to be stored at the specified position |
324 |
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* @return the element previously at the specified position |
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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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Entry<E> e = entry(index); |
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* Shifts the element currently at that position (if any) and any |
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* subsequent elements to the right (adds one to their indices). |
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* |
339 |
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* @param index index at which the specified element is to be inserted. |
340 |
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* @param element element to be inserted. |
341 |
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* |
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* @throws IndexOutOfBoundsException if the index is out of range |
341 |
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* (<tt>index < 0 || index > size()</tt>). |
339 |
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* @param index index at which the specified element is to be inserted |
340 |
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* @param element element to be inserted |
341 |
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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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addBefore(element, (index==size ? header : entry(index))); |
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* subsequent elements to the left (subtracts one from their indices). |
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* Returns the element that was removed from the list. |
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* |
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* @param index the index of the element to removed. |
353 |
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* @return the element previously at the specified position. |
354 |
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* |
355 |
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* @throws IndexOutOfBoundsException if the index is out of range |
356 |
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* (<tt>index < 0 || index > size()</tt>). |
352 |
> |
* @param index the index of the element to be removed |
353 |
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* @return the element previously at the specified position |
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* @throws IndexOutOfBoundsException {@inheritDoc} |
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*/ |
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public E remove(int index) { |
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return remove(entry(index)); |
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// Search Operations |
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|
381 |
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/** |
382 |
< |
* Returns the index in this list of the first occurrence of the |
383 |
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* specified element, or -1 if the List does not contain this |
384 |
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* element. More formally, returns the lowest index i such that |
385 |
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* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, or -1 if |
386 |
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* there is no such index. |
387 |
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* |
388 |
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* @param o element to search for. |
389 |
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* @return the index in this list of the first occurrence of the |
390 |
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* specified element, or -1 if the list does not contain this |
393 |
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* element. |
382 |
> |
* Returns the index of the first occurrence of the specified element |
383 |
> |
* in this list, or -1 if this list does not contain the element. |
384 |
> |
* More formally, returns the lowest index <tt>i</tt> such that |
385 |
> |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
386 |
> |
* or -1 if there is no such index. |
387 |
> |
* |
388 |
> |
* @param o element to search for |
389 |
> |
* @return the index of the first occurrence of the specified element in |
390 |
> |
* this list, or -1 if this list does not contain the element |
391 |
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*/ |
392 |
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public int indexOf(Object o) { |
393 |
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int index = 0; |
408 |
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} |
409 |
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|
410 |
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/** |
411 |
< |
* Returns the index in this list of the last occurrence of the |
412 |
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* specified element, or -1 if the list does not contain this |
413 |
< |
* element. More formally, returns the highest index i such that |
414 |
< |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, or -1 if |
415 |
< |
* there is no such index. |
416 |
< |
* |
417 |
< |
* @param o element to search for. |
418 |
< |
* @return the index in this list of the last occurrence of the |
419 |
< |
* specified element, or -1 if the list does not contain this |
423 |
< |
* element. |
411 |
> |
* Returns the index of the last occurrence of the specified element |
412 |
> |
* in this list, or -1 if this list does not contain the element. |
413 |
> |
* More formally, returns the highest index <tt>i</tt> such that |
414 |
> |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
415 |
> |
* or -1 if there is no such index. |
416 |
> |
* |
417 |
> |
* @param o element to search for |
418 |
> |
* @return the index of the last occurrence of the specified element in |
419 |
> |
* this list, or -1 if this list does not contain the element |
420 |
|
*/ |
421 |
|
public int lastIndexOf(Object o) { |
422 |
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int index = size; |
440 |
|
|
441 |
|
/** |
442 |
|
* Retrieves, but does not remove, the head (first element) of this list. |
443 |
< |
* @return the head of this list, or <tt>null</tt> if this list is empty. |
443 |
> |
* @return the head of this list, or <tt>null</tt> if this list is empty |
444 |
|
* @since 1.5 |
445 |
|
*/ |
446 |
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public E peek() { |
451 |
|
|
452 |
|
/** |
453 |
|
* Retrieves, but does not remove, the head (first element) of this list. |
454 |
< |
* @return the head of this list. |
455 |
< |
* @throws NoSuchElementException if this list is empty. |
454 |
> |
* @return the head of this list |
455 |
> |
* @throws NoSuchElementException if this list is empty |
456 |
|
* @since 1.5 |
457 |
|
*/ |
458 |
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public E element() { |
460 |
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} |
461 |
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|
462 |
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/** |
463 |
< |
* Retrieves and removes the head (first element) of this list. |
464 |
< |
* @return the head of this list, or <tt>null</tt> if this list is empty. |
463 |
> |
* Retrieves and removes the head (first element) of this list |
464 |
> |
* @return the head of this list, or <tt>null</tt> if this list is empty |
465 |
|
* @since 1.5 |
466 |
|
*/ |
467 |
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public E poll() { |
472 |
|
|
473 |
|
/** |
474 |
|
* Retrieves and removes the head (first element) of this list. |
475 |
< |
* @return the head of this list. |
476 |
< |
* @throws NoSuchElementException if this list is empty. |
475 |
> |
* |
476 |
> |
* @return the head of this list |
477 |
> |
* @throws NoSuchElementException if this list is empty |
478 |
|
* @since 1.5 |
479 |
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*/ |
480 |
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public E remove() { |
484 |
|
/** |
485 |
|
* Adds the specified element as the tail (last element) of this list. |
486 |
|
* |
487 |
< |
* @param e the element to add. |
488 |
< |
* @return <tt>true</tt> (as per the general contract of |
492 |
< |
* <tt>Queue.offer</tt>) |
487 |
> |
* @param e the element to add |
488 |
> |
* @return <tt>true</tt> (as specified by {@link Queue#offer}) |
489 |
|
* @since 1.5 |
490 |
|
*/ |
491 |
|
public boolean offer(E e) { |
497 |
|
* Inserts the specified element at the front of this list. |
498 |
|
* |
499 |
|
* @param e the element to insert |
500 |
< |
* @return <tt>true</tt> (as per the spec for {@link Deque#offerFirst}) |
500 |
> |
* @return <tt>true</tt> (as specified by {@link Deque#offerFirst}) |
501 |
|
* @since 1.6 |
502 |
|
*/ |
503 |
|
public boolean offerFirst(E e) { |
509 |
|
* Inserts the specified element at the end of this list. |
510 |
|
* |
511 |
|
* @param e the element to insert |
512 |
< |
* @return <tt>true</tt> (as per the spec for {@link Deque#offerLast}) |
512 |
> |
* @return <tt>true</tt> (as specified by {@link Deque#offerLast}) |
513 |
|
* @since 1.6 |
514 |
|
*/ |
515 |
|
public boolean offerLast(E e) { |
519 |
|
|
520 |
|
/** |
521 |
|
* Retrieves, but does not remove, the first element of this list, |
522 |
< |
* returning <tt>null</tt> if this list is empty. |
522 |
> |
* or returns <tt>null</tt> if this list is empty. |
523 |
|
* |
524 |
< |
* @return the first element of this list, or <tt>null</tt> if |
525 |
< |
* this list is empty |
524 |
> |
* @return the first element of this list, or <tt>null</tt> |
525 |
> |
* if this list is empty |
526 |
|
* @since 1.6 |
527 |
|
*/ |
528 |
|
public E peekFirst() { |
533 |
|
|
534 |
|
/** |
535 |
|
* Retrieves, but does not remove, the last element of this list, |
536 |
< |
* returning <tt>null</tt> if this list is empty. |
536 |
> |
* or returns <tt>null</tt> if this list is empty. |
537 |
|
* |
538 |
< |
* @return the last element of this list, or <tt>null</tt> if this list |
539 |
< |
* is empty |
538 |
> |
* @return the last element of this list, or <tt>null</tt> |
539 |
> |
* if this list is empty |
540 |
|
* @since 1.6 |
541 |
|
*/ |
542 |
|
public E peekLast() { |
546 |
|
} |
547 |
|
|
548 |
|
/** |
549 |
< |
* Retrieves and removes the first element of this list, or |
550 |
< |
* <tt>null</tt> if this list is empty. |
549 |
> |
* Retrieves and removes the first element of this list, |
550 |
> |
* or returns <tt>null</tt> if this list is empty. |
551 |
|
* |
552 |
|
* @return the first element of this list, or <tt>null</tt> if |
553 |
|
* this list is empty |
560 |
|
} |
561 |
|
|
562 |
|
/** |
563 |
< |
* Retrieves and removes the last element of this list, or |
564 |
< |
* <tt>null</tt> if this list is empty. |
563 |
> |
* Retrieves and removes the last element of this list, |
564 |
> |
* or returns <tt>null</tt> if this list is empty. |
565 |
|
* |
566 |
|
* @return the last element of this list, or <tt>null</tt> if |
567 |
|
* this list is empty |
593 |
|
* <p>This method is equivalent to {@link #removeFirst()}. |
594 |
|
* |
595 |
|
* @return the element at the front of this list (which is the top |
596 |
< |
* of the stack represented by this list) |
597 |
< |
* @throws NoSuchElementException if this list is empty. |
596 |
> |
* of the stack represented by this list) |
597 |
> |
* @throws NoSuchElementException if this list is empty |
598 |
|
* @since 1.6 |
599 |
|
*/ |
600 |
|
public E pop() { |
625 |
|
*/ |
626 |
|
public boolean removeLastOccurrence(Object o) { |
627 |
|
if (o==null) { |
628 |
< |
for (Entry e = header.previous; e != header; e = e.previous) { |
628 |
> |
for (Entry<E> e = header.previous; e != header; e = e.previous) { |
629 |
|
if (e.element==null) { |
630 |
|
remove(e); |
631 |
|
return true; |
632 |
|
} |
633 |
|
} |
634 |
|
} else { |
635 |
< |
for (Entry e = header.previous; e != header; e = e.previous) { |
635 |
> |
for (Entry<E> e = header.previous; e != header; e = e.previous) { |
636 |
|
if (o.equals(e.element)) { |
637 |
|
remove(e); |
638 |
|
return true; |
656 |
|
* than risking arbitrary, non-deterministic behavior at an undetermined |
657 |
|
* time in the future. |
658 |
|
* |
659 |
< |
* @param index index of first element to be returned from the |
660 |
< |
* list-iterator (by a call to <tt>next</tt>). |
659 |
> |
* @param index index of the first element to be returned from the |
660 |
> |
* list-iterator (by a call to <tt>next</tt>) |
661 |
|
* @return a ListIterator of the elements in this list (in proper |
662 |
< |
* sequence), starting at the specified position in the list. |
663 |
< |
* @throws IndexOutOfBoundsException if the index is out of range |
668 |
< |
* (<tt>index < 0 || index > size()</tt>). |
662 |
> |
* sequence), starting at the specified position in the list |
663 |
> |
* @throws IndexOutOfBoundsException {@inheritDoc} |
664 |
|
* @see List#listIterator(int) |
665 |
|
*/ |
666 |
|
public ListIterator<E> listIterator(int index) { |
798 |
|
} |
799 |
|
|
800 |
|
/** |
801 |
+ |
* @since 1.6 |
802 |
+ |
*/ |
803 |
+ |
public Iterator<E> descendingIterator() { |
804 |
+ |
return new DescendingIterator(); |
805 |
+ |
} |
806 |
+ |
|
807 |
+ |
/** Adapter to provide descending iterators via ListItr.previous */ |
808 |
+ |
private class DescendingIterator implements Iterator { |
809 |
+ |
final ListItr itr = new ListItr(size()); |
810 |
+ |
public boolean hasNext() { |
811 |
+ |
return itr.hasPrevious(); |
812 |
+ |
} |
813 |
+ |
public E next() { |
814 |
+ |
return itr.previous(); |
815 |
+ |
} |
816 |
+ |
public void remove() { |
817 |
+ |
itr.remove(); |
818 |
+ |
} |
819 |
+ |
} |
820 |
+ |
|
821 |
+ |
/** |
822 |
|
* Returns a shallow copy of this <tt>LinkedList</tt>. (The elements |
823 |
|
* themselves are not cloned.) |
824 |
|
* |
825 |
< |
* @return a shallow copy of this <tt>LinkedList</tt> instance. |
825 |
> |
* @return a shallow copy of this <tt>LinkedList</tt> instance |
826 |
|
*/ |
827 |
|
public Object clone() { |
828 |
|
LinkedList<E> clone = null; |
847 |
|
|
848 |
|
/** |
849 |
|
* Returns an array containing all of the elements in this list |
850 |
< |
* in the correct order. |
850 |
> |
* in proper sequence (from first to last element). |
851 |
> |
* |
852 |
> |
* <p>The returned array will be "safe" in that no references to it are |
853 |
> |
* maintained by this list. (In other words, this method must allocate |
854 |
> |
* a new array). The caller is thus free to modify the returned array. |
855 |
> |
* |
856 |
> |
* <p>This method acts as bridge between array-based and collection-based |
857 |
> |
* APIs. |
858 |
|
* |
859 |
|
* @return an array containing all of the elements in this list |
860 |
< |
* in the correct order. |
860 |
> |
* in proper sequence |
861 |
|
*/ |
862 |
|
public Object[] toArray() { |
863 |
|
Object[] result = new Object[size]; |
869 |
|
|
870 |
|
/** |
871 |
|
* Returns an array containing all of the elements in this list in |
872 |
< |
* the correct order; the runtime type of the returned array is that of |
873 |
< |
* the specified array. If the list fits in the specified array, it |
874 |
< |
* is returned therein. Otherwise, a new array is allocated with the |
875 |
< |
* runtime type of the specified array and the size of this list.<p> |
876 |
< |
* |
877 |
< |
* If the list fits in the specified array with room to spare |
878 |
< |
* (i.e., the array has more elements than the list), |
879 |
< |
* the element in the array immediately following the end of the |
880 |
< |
* collection is set to null. This is useful in determining the length |
881 |
< |
* of the list <i>only</i> if the caller knows that the list |
882 |
< |
* does not contain any null elements. |
872 |
> |
* proper sequence (from first to last element); the runtime type of |
873 |
> |
* the returned array is that of the specified array. If the list fits |
874 |
> |
* in the specified array, it is returned therein. Otherwise, a new |
875 |
> |
* array is allocated with the runtime type of the specified array and |
876 |
> |
* the size of this list. |
877 |
> |
* |
878 |
> |
* <p>If the list fits in the specified array with room to spare (i.e., |
879 |
> |
* the array has more elements than the list), the element in the array |
880 |
> |
* immediately following the end of the list is set to <tt>null</tt>. |
881 |
> |
* (This is useful in determining the length of the list <i>only</i> if |
882 |
> |
* the caller knows that the list does not contain any null elements.) |
883 |
> |
* |
884 |
> |
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
885 |
> |
* array-based and collection-based APIs. Further, this method allows |
886 |
> |
* precise control over the runtime type of the output array, and may, |
887 |
> |
* under certain circumstances, be used to save allocation costs. |
888 |
> |
* |
889 |
> |
* <p>Suppose <tt>x</tt> is a list known to contain only strings. |
890 |
> |
* The following code can be used to dump the list into a newly |
891 |
> |
* allocated array of <tt>String</tt>: |
892 |
> |
* |
893 |
> |
* <pre> |
894 |
> |
* String[] y = x.toArray(new String[0]);</pre> |
895 |
> |
* |
896 |
> |
* Note that <tt>toArray(new Object[0])</tt> is identical in function to |
897 |
> |
* <tt>toArray()</tt>. |
898 |
|
* |
899 |
|
* @param a the array into which the elements of the list are to |
900 |
< |
* be stored, if it is big enough; otherwise, a new array of the |
901 |
< |
* same runtime type is allocated for this purpose. |
902 |
< |
* @return an array containing the elements of the list. |
903 |
< |
* @throws ArrayStoreException if the runtime type of a is not a |
904 |
< |
* supertype of the runtime type of every element in this list. |
905 |
< |
* @throws NullPointerException if the specified array is null. |
900 |
> |
* be stored, if it is big enough; otherwise, a new array of the |
901 |
> |
* same runtime type is allocated for this purpose. |
902 |
> |
* @return an array containing the elements of the list |
903 |
> |
* @throws ArrayStoreException if the runtime type of the specified array |
904 |
> |
* is not a supertype of the runtime type of every element in |
905 |
> |
* this list |
906 |
> |
* @throws NullPointerException if the specified array is null |
907 |
|
*/ |
908 |
|
public <T> T[] toArray(T[] a) { |
909 |
|
if (a.length < size) |
927 |
|
* is, serialize it). |
928 |
|
* |
929 |
|
* @serialData The size of the list (the number of elements it |
930 |
< |
* contains) is emitted (int), followed by all of its |
931 |
< |
* elements (each an Object) in the proper order. |
930 |
> |
* contains) is emitted (int), followed by all of its |
931 |
> |
* elements (each an Object) in the proper order. |
932 |
|
*/ |
933 |
|
private void writeObject(java.io.ObjectOutputStream s) |
934 |
|
throws java.io.IOException { |