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/* |
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* %W% %E% |
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* Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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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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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Sun designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Sun in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
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* CA 95054 USA or visit www.sun.com if you need additional information or |
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* have any questions. |
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*/ |
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package java.util; |
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/** |
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* An unbounded priority {@linkplain Queue queue} based on a priority |
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* heap. The elements of the priority queue are ordered according to |
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* their {@linkplain Comparable natural ordering}, or by a {@link |
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* Comparator} provided at queue construction time, depending on which |
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* constructor is used. A priority queue does not permit |
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* <tt>null</tt> elements. A priority queue relying on natural |
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* ordering also does not permit insertion of non-comparable objects |
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* (doing so may result in <tt>ClassCastException</tt>). |
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* An unbounded priority {@linkplain Queue queue} based on a priority heap. |
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* The elements of the priority queue are ordered according to their |
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* {@linkplain Comparable natural ordering}, or by a {@link Comparator} |
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* provided at queue construction time, depending on which constructor is |
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* used. A priority queue does not permit {@code null} elements. |
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* A priority queue relying on natural ordering also does not permit |
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* insertion of non-comparable objects (doing so may result in |
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* {@code ClassCastException}). |
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* |
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* <p>The <em>head</em> of this queue is the <em>least</em> element |
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* with respect to the specified ordering. If multiple elements are |
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* tied for least value, the head is one of those elements -- ties are |
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* broken arbitrarily. The queue retrieval operations <tt>poll</tt>, |
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* <tt>remove</tt>, <tt>peek</tt>, and <tt>element</tt> access the |
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* broken arbitrarily. The queue retrieval operations {@code poll}, |
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* {@code remove}, {@code peek}, and {@code element} access the |
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* element at the head of the queue. |
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* |
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* <p>A priority queue is unbounded, but has an internal |
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* Iterator} interfaces. The Iterator provided in method {@link |
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* #iterator()} is <em>not</em> guaranteed to traverse the elements of |
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* the priority queue in any particular order. If you need ordered |
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* traversal, consider using <tt>Arrays.sort(pq.toArray())</tt>. |
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* traversal, consider using {@code Arrays.sort(pq.toArray())}. |
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* |
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* <p> <strong>Note that this implementation is not synchronized.</strong> |
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* Multiple threads should not access a <tt>PriorityQueue</tt> |
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* instance concurrently if any of the threads modifies the list |
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* structurally. Instead, use the thread-safe {@link |
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* Multiple threads should not access a {@code PriorityQueue} |
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* instance concurrently if any of the threads modifies the queue. |
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* Instead, use the thread-safe {@link |
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* java.util.concurrent.PriorityBlockingQueue} class. |
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* |
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* <p>Implementation note: this implementation provides O(log(n)) time |
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* for the insertion methods (<tt>offer</tt>, <tt>poll</tt>, |
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* <tt>remove()</tt> and <tt>add</tt>) methods; linear time for the |
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* <tt>remove(Object)</tt> and <tt>contains(Object)</tt> methods; and |
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* constant time for the retrieval methods (<tt>peek</tt>, |
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* <tt>element</tt>, and <tt>size</tt>). |
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* <p>Implementation note: this implementation provides |
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* O(log(n)) time for the enqueing and dequeing methods |
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* ({@code offer}, {@code poll}, {@code remove()} and {@code add}); |
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* linear time for the {@code remove(Object)} and {@code contains(Object)} |
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* methods; and constant time for the retrieval methods |
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* ({@code peek}, {@code element}, and {@code size}). |
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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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* @since 1.5 |
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* @version %I%, %G% |
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* @author Josh Bloch |
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* @author Josh Bloch, Doug Lea |
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* @param <E> the type of elements held in this collection |
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*/ |
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public class PriorityQueue<E> extends AbstractQueue<E> |
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private transient int modCount = 0; |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> with the default initial |
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* Creates a {@code PriorityQueue} with the default initial |
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* capacity (11) that orders its elements according to their |
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* {@linkplain Comparable natural ordering}. |
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*/ |
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} |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> with the specified initial |
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* Creates a {@code PriorityQueue} with the specified initial |
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* capacity that orders its elements according to their |
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* {@linkplain Comparable natural ordering}. |
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* |
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* @param initialCapacity the initial capacity for this priority queue |
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* @throws IllegalArgumentException if <tt>initialCapacity</tt> is less |
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* than 1 |
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* @throws IllegalArgumentException if {@code initialCapacity} is less |
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* than 1 |
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*/ |
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public PriorityQueue(int initialCapacity) { |
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this(initialCapacity, null); |
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} |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> with the specified initial capacity |
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* Creates a {@code PriorityQueue} with the specified initial capacity |
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* that orders its elements according to the specified comparator. |
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* |
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* @param initialCapacity the initial capacity for this priority queue |
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* @param comparator the comparator that will be used to order |
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* this priority queue. If <tt>null</tt>, the <i>natural |
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* ordering</i> of the elements will be used. |
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* @throws IllegalArgumentException if <tt>initialCapacity</tt> is |
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* @param comparator the comparator that will be used to order this |
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* priority queue. If {@code null}, the {@linkplain Comparable |
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* natural ordering} of the elements will be used. |
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* @throws IllegalArgumentException if {@code initialCapacity} is |
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* less than 1 |
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*/ |
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public PriorityQueue(int initialCapacity, |
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} |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> containing the elements in the |
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* specified collection. If the specified collection is an |
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* instance of a {@link java.util.SortedSet} or is another |
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* <tt>PriorityQueue</tt>, the priority queue will be ordered |
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* according to the same ordering. Otherwise, this priority queue |
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* will be ordered according to the natural ordering of its elements. |
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* Creates a {@code PriorityQueue} containing the elements in the |
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* specified collection. If the specified collection is an instance of |
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* a {@link SortedSet} or is another {@code PriorityQueue}, this |
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* priority queue will be ordered according to the same ordering. |
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* Otherwise, this priority queue will be ordered according to the |
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* {@linkplain Comparable natural ordering} of its elements. |
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* |
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* @param c the collection whose elements are to be placed |
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* into this priority queue |
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} |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> containing the elements in the |
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* Creates a {@code PriorityQueue} containing the elements in the |
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* specified priority queue. This priority queue will be |
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* ordered according to the same ordering as the given priority |
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* queue. |
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* |
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* @param c the priority queue whose elements are to be placed |
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* into this priority queue |
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* @throws ClassCastException if elements of <tt>c</tt> cannot be |
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* compared to one another according to <tt>c</tt>'s |
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* @throws ClassCastException if elements of {@code c} cannot be |
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* compared to one another according to {@code c}'s |
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* ordering |
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* @throws NullPointerException if the specified priority queue or any |
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* of its elements are null |
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} |
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|
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/** |
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* Creates a <tt>PriorityQueue</tt> containing the elements in the |
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* specified sorted set. This priority queue will be ordered |
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* Creates a {@code PriorityQueue} containing the elements in the |
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* specified sorted set. This priority queue will be ordered |
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* according to the same ordering as the given sorted set. |
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* |
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* @param c the sorted set whose elements are to be placed |
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* into this priority queue. |
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* into this priority queue |
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* @throws ClassCastException if elements of the specified sorted |
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* set cannot be compared to one another according to the |
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* sorted set's ordering |
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} |
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/** |
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* Initialize queue array with elements from the given Collection. |
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* Initializes queue array with elements from the given Collection. |
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* |
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* @param c the collection |
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*/ |
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private void initFromCollection(Collection<? extends E> c) { |
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private void grow(int minCapacity) { |
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if (minCapacity < 0) // overflow |
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throw new OutOfMemoryError(); |
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int oldCapacity = queue.length; |
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int oldCapacity = queue.length; |
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// Double size if small; else grow by 50% |
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int newCapacity = ((oldCapacity < 64)? |
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((oldCapacity + 1) * 2): |
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/** |
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* Inserts the specified element into this priority queue. |
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* |
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* @return <tt>true</tt> (as specified by {@link Collection#add}) |
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* @return {@code true} (as specified by {@link Collection#add}) |
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* @throws ClassCastException if the specified element cannot be |
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* compared with elements currently in this priority queue |
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* according to the priority queue's ordering |
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/** |
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* Inserts the specified element into this priority queue. |
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* |
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* @return <tt>true</tt> (as specified by {@link Queue#offer}) |
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* @return {@code true} (as specified by {@link Queue#offer}) |
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* @throws ClassCastException if the specified element cannot be |
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* compared with elements currently in this priority queue |
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* according to the priority queue's ordering |
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} |
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|
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private int indexOf(Object o) { |
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if (o != null) { |
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if (o != null) { |
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for (int i = 0; i < size; i++) |
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if (o.equals(queue[i])) |
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return i; |
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|
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/** |
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* Removes a single instance of the specified element from this queue, |
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* if it is present. More formally, removes an element <tt>e</tt> such |
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* that <tt>o.equals(e)</tt>, if this queue contains one or more such |
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* elements. Returns true if this queue contained the specified element |
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* (or equivalently, if this queue changed as a result of the call). |
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* if it is present. More formally, removes an element {@code e} such |
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* that {@code o.equals(e)}, if this queue contains one or more such |
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* elements. Returns {@code true} if and only if this queue contained |
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* the specified element (or equivalently, if this queue changed as a |
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> |
* result of the call). |
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* |
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* @param o element to be removed from this queue, if present |
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< |
* @return <tt>true</tt> if this queue changed as a result of the call |
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> |
* @return {@code true} if this queue changed as a result of the call |
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*/ |
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public boolean remove(Object o) { |
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int i = indexOf(o); |
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< |
if (i == -1) |
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< |
return false; |
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else { |
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< |
removeAt(i); |
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< |
return true; |
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} |
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> |
int i = indexOf(o); |
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> |
if (i == -1) |
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return false; |
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else { |
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removeAt(i); |
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return true; |
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} |
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} |
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|
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/** |
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* Needed by iterator.remove. |
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* |
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* @param o element to be removed from this queue, if present |
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< |
* @return <tt>true</tt> if removed |
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> |
* @return {@code true} if removed |
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*/ |
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boolean removeEq(Object o) { |
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< |
for (int i = 0; i < size; i++) { |
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< |
if (o == queue[i]) { |
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> |
for (int i = 0; i < size; i++) { |
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> |
if (o == queue[i]) { |
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removeAt(i); |
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return true; |
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} |
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} |
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|
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/** |
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< |
* Returns <tt>true</tt> if this queue contains the specified element. |
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< |
* More formally, returns <tt>true</tt> if and only if this queue contains |
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< |
* at least one element <tt>e</tt> such that <tt>o.equals(e)</tt>. |
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> |
* Returns {@code true} if this queue contains the specified element. |
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> |
* More formally, returns {@code true} if and only if this queue contains |
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> |
* at least one element {@code e} such that {@code o.equals(e)}. |
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* |
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* @param o object to be checked for containment in this queue |
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< |
* @return <tt>true</tt> if this queue contains the specified element |
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> |
* @return {@code true} if this queue 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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> |
return indexOf(o) != -1; |
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} |
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|
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/** |
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< |
* Returns an array containing all of the elements in this queue, |
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> |
* Returns an array containing all of the elements in this queue. |
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* The elements are in no particular order. |
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* |
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* <p>The returned array will be "safe" in that no references to it are |
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< |
* maintained by this list. (In other words, this method must allocate |
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> |
* maintained by this queue. (In other words, this method must allocate |
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* a new array). The caller is thus free to modify the returned array. |
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* |
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+ |
* <p>This method acts as bridge between array-based and collection-based |
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+ |
* APIs. |
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+ |
* |
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* @return an array containing all of the elements in this queue |
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*/ |
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public Object[] toArray() { |
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} |
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|
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/** |
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< |
* Returns an array containing all of the elements in this queue. |
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< |
* The elements are in no particular order. The runtime type of |
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< |
* the returned array is that of the specified array. If the queue |
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< |
* fits in the specified array, it is returned therein. |
| 382 |
< |
* Otherwise, a new array is allocated with the runtime type of |
| 383 |
< |
* the specified array and the size of this queue. |
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> |
* Returns an array containing all of the elements in this queue; the |
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> |
* runtime type of the returned array is that of the specified array. |
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> |
* The returned array elements are in no particular order. |
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> |
* If the queue fits in the specified array, it is returned therein. |
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> |
* Otherwise, a new array is allocated with the runtime type of the |
| 383 |
> |
* specified array and the size of this queue. |
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* |
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* <p>If the queue fits in the specified array with room to spare |
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* (i.e., the array has more elements than the queue), the element in |
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* the array immediately following the end of the collection is set to |
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< |
* <tt>null</tt>. (This is useful in determining the length of the |
| 389 |
< |
* queue <i>only</i> if the caller knows that the queue does not contain |
| 390 |
< |
* any null elements.) |
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> |
* {@code null}. |
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> |
* |
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> |
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
| 391 |
> |
* array-based and collection-based APIs. Further, this method allows |
| 392 |
> |
* precise control over the runtime type of the output array, and may, |
| 393 |
> |
* under certain circumstances, be used to save allocation costs. |
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> |
* |
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> |
* <p>Suppose <tt>x</tt> is a queue known to contain only strings. |
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> |
* The following code can be used to dump the queue into a newly |
| 397 |
> |
* allocated array of <tt>String</tt>: |
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> |
* |
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> |
* <pre> |
| 400 |
> |
* String[] y = x.toArray(new String[0]);</pre> |
| 401 |
> |
* |
| 402 |
> |
* Note that <tt>toArray(new Object[0])</tt> is identical in function to |
| 403 |
> |
* <tt>toArray()</tt>. |
| 404 |
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* |
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* @param a the array into which the elements of the queue are to |
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* be stored, if it is big enough; otherwise, a new array of the |
| 407 |
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* same runtime type is allocated for this purpose. |
| 408 |
< |
* @return an array containing the elements of the queue |
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> |
* @return an array containing all of the elements in this queue |
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|
* @throws ArrayStoreException if the runtime type of the specified array |
| 410 |
|
* is not a supertype of the runtime type of every element in |
| 411 |
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* this queue |
| 415 |
|
if (a.length < size) |
| 416 |
|
// Make a new array of a's runtime type, but my contents: |
| 417 |
|
return (T[]) Arrays.copyOf(queue, size, a.getClass()); |
| 418 |
< |
System.arraycopy(queue, 0, a, 0, size); |
| 418 |
> |
System.arraycopy(queue, 0, a, 0, size); |
| 419 |
|
if (a.length > size) |
| 420 |
|
a[size] = null; |
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return a; |
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* after we've completed the "normal" iteration. |
| 455 |
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* |
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|
* We expect that most iterations, even those involving removals, |
| 457 |
< |
* will not use need to store elements in this field. |
| 457 |
> |
* will not need to store elements in this field. |
| 458 |
|
*/ |
| 459 |
|
private ArrayDeque<E> forgetMeNot = null; |
| 460 |
|
|
| 466 |
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|
| 467 |
|
/** |
| 468 |
|
* The modCount value that the iterator believes that the backing |
| 469 |
< |
* List should have. If this expectation is violated, the iterator |
| 469 |
> |
* Queue should have. If this expectation is violated, the iterator |
| 470 |
|
* has detected concurrent modification. |
| 471 |
|
*/ |
| 472 |
|
private int expectedModCount = modCount; |
| 493 |
|
public void remove() { |
| 494 |
|
if (expectedModCount != modCount) |
| 495 |
|
throw new ConcurrentModificationException(); |
| 460 |
– |
if (lastRet == -1 && lastRetElt == null) |
| 461 |
– |
throw new IllegalStateException(); |
| 496 |
|
if (lastRet != -1) { |
| 497 |
|
E moved = PriorityQueue.this.removeAt(lastRet); |
| 498 |
|
lastRet = -1; |
| 503 |
|
forgetMeNot = new ArrayDeque<E>(); |
| 504 |
|
forgetMeNot.add(moved); |
| 505 |
|
} |
| 506 |
< |
} else { |
| 506 |
> |
} else if (lastRetElt != null) { |
| 507 |
|
PriorityQueue.this.removeEq(lastRetElt); |
| 508 |
|
lastRetElt = null; |
| 509 |
+ |
} else { |
| 510 |
+ |
throw new IllegalStateException(); |
| 511 |
|
} |
| 512 |
|
expectedModCount = modCount; |
| 513 |
|
} |
| 478 |
– |
|
| 514 |
|
} |
| 515 |
|
|
| 516 |
|
public int size() { |
| 533 |
|
return null; |
| 534 |
|
int s = --size; |
| 535 |
|
modCount++; |
| 536 |
< |
E result = (E)queue[0]; |
| 537 |
< |
E x = (E)queue[s]; |
| 536 |
> |
E result = (E) queue[0]; |
| 537 |
> |
E x = (E) queue[s]; |
| 538 |
|
queue[s] = null; |
| 539 |
|
if (s != 0) |
| 540 |
|
siftDown(0, x); |
| 551 |
|
* i. Under these circumstances, this method returns the element |
| 552 |
|
* that was previously at the end of the list and is now at some |
| 553 |
|
* position before i. This fact is used by iterator.remove so as to |
| 554 |
< |
* avoid missing traverseing elements. |
| 554 |
> |
* avoid missing traversing elements. |
| 555 |
|
*/ |
| 556 |
|
private E removeAt(int i) { |
| 557 |
|
assert i >= 0 && i < size; |
| 596 |
|
while (k > 0) { |
| 597 |
|
int parent = (k - 1) >>> 1; |
| 598 |
|
Object e = queue[parent]; |
| 599 |
< |
if (key.compareTo((E)e) >= 0) |
| 599 |
> |
if (key.compareTo((E) e) >= 0) |
| 600 |
|
break; |
| 601 |
|
queue[k] = e; |
| 602 |
|
k = parent; |
| 608 |
|
while (k > 0) { |
| 609 |
|
int parent = (k - 1) >>> 1; |
| 610 |
|
Object e = queue[parent]; |
| 611 |
< |
if (comparator.compare(x, (E)e) >= 0) |
| 611 |
> |
if (comparator.compare(x, (E) e) >= 0) |
| 612 |
|
break; |
| 613 |
|
queue[k] = e; |
| 614 |
|
k = parent; |
| 639 |
|
Object c = queue[child]; |
| 640 |
|
int right = child + 1; |
| 641 |
|
if (right < size && |
| 642 |
< |
((Comparable<? super E>)c).compareTo((E)queue[right]) > 0) |
| 642 |
> |
((Comparable<? super E>) c).compareTo((E) queue[right]) > 0) |
| 643 |
|
c = queue[child = right]; |
| 644 |
< |
if (key.compareTo((E)c) <= 0) |
| 644 |
> |
if (key.compareTo((E) c) <= 0) |
| 645 |
|
break; |
| 646 |
|
queue[k] = c; |
| 647 |
|
k = child; |
| 656 |
|
Object c = queue[child]; |
| 657 |
|
int right = child + 1; |
| 658 |
|
if (right < size && |
| 659 |
< |
comparator.compare((E)c, (E)queue[right]) > 0) |
| 659 |
> |
comparator.compare((E) c, (E) queue[right]) > 0) |
| 660 |
|
c = queue[child = right]; |
| 661 |
< |
if (comparator.compare(x, (E)c) <= 0) |
| 661 |
> |
if (comparator.compare(x, (E) c) <= 0) |
| 662 |
|
break; |
| 663 |
|
queue[k] = c; |
| 664 |
|
k = child; |
| 672 |
|
*/ |
| 673 |
|
private void heapify() { |
| 674 |
|
for (int i = (size >>> 1) - 1; i >= 0; i--) |
| 675 |
< |
siftDown(i, (E)queue[i]); |
| 675 |
> |
siftDown(i, (E) queue[i]); |
| 676 |
|
} |
| 677 |
|
|
| 678 |
|
/** |
| 679 |
|
* Returns the comparator used to order the elements in this |
| 680 |
< |
* queue, or <tt>null</tt> if this queue is sorted according to |
| 680 |
> |
* queue, or {@code null} if this queue is sorted according to |
| 681 |
|
* the {@linkplain Comparable natural ordering} of its elements. |
| 682 |
|
* |
| 683 |
|
* @return the comparator used to order this queue, or |
| 684 |
< |
* <tt>null</tt> if this queue is sorted according to the |
| 685 |
< |
* natural ordering of its elements. |
| 684 |
> |
* {@code null} if this queue is sorted according to the |
| 685 |
> |
* natural ordering of its elements |
| 686 |
|
*/ |
| 687 |
|
public Comparator<? super E> comparator() { |
| 688 |
|
return comparator; |
| 689 |
|
} |
| 690 |
|
|
| 691 |
|
/** |
| 692 |
< |
* Save the state of the instance to a stream (that |
| 693 |
< |
* is, serialize it). |
| 692 |
> |
* Saves the state of the instance to a stream (that |
| 693 |
> |
* is, serializes it). |
| 694 |
|
* |
| 695 |
|
* @serialData The length of the array backing the instance is |
| 696 |
< |
* emitted (int), followed by all of its elements (each an |
| 697 |
< |
* <tt>Object</tt>) in the proper order. |
| 696 |
> |
* emitted (int), followed by all of its elements |
| 697 |
> |
* (each an {@code Object}) in the proper order. |
| 698 |
|
* @param s the stream |
| 699 |
|
*/ |
| 700 |
|
private void writeObject(java.io.ObjectOutputStream s) |
| 702 |
|
// Write out element count, and any hidden stuff |
| 703 |
|
s.defaultWriteObject(); |
| 704 |
|
|
| 705 |
< |
// Write out array length |
| 706 |
< |
// For compatibility with 1.5 version, must be at least 2. |
| 672 |
< |
s.writeInt(Math.max(2, queue.length)); |
| 705 |
> |
// Write out array length, for compatibility with 1.5 version |
| 706 |
> |
s.writeInt(Math.max(2, size + 1)); |
| 707 |
|
|
| 708 |
< |
// Write out all elements in the proper order. |
| 709 |
< |
for (int i=0; i<size; i++) |
| 708 |
> |
// Write out all elements in the "proper order". |
| 709 |
> |
for (int i = 0; i < size; i++) |
| 710 |
|
s.writeObject(queue[i]); |
| 711 |
|
} |
| 712 |
|
|
| 713 |
|
/** |
| 714 |
< |
* Reconstitute the <tt>PriorityQueue</tt> instance from a stream |
| 715 |
< |
* (that is, deserialize it). |
| 714 |
> |
* Reconstitutes the {@code PriorityQueue} instance from a stream |
| 715 |
> |
* (that is, deserializes it). |
| 716 |
> |
* |
| 717 |
|
* @param s the stream |
| 718 |
|
*/ |
| 719 |
|
private void readObject(java.io.ObjectInputStream s) |
| 721 |
|
// Read in size, and any hidden stuff |
| 722 |
|
s.defaultReadObject(); |
| 723 |
|
|
| 724 |
< |
// Read in array length and allocate array |
| 725 |
< |
int arrayLength = s.readInt(); |
| 726 |
< |
queue = new Object[arrayLength]; |
| 727 |
< |
|
| 693 |
< |
// Read in all elements in the proper order. |
| 694 |
< |
for (int i=0; i<size; i++) |
| 695 |
< |
queue[i] = (E) s.readObject(); |
| 696 |
< |
} |
| 724 |
> |
// Read in (and discard) array length |
| 725 |
> |
s.readInt(); |
| 726 |
> |
|
| 727 |
> |
queue = new Object[size]; |
| 728 |
|
|
| 729 |
+ |
// Read in all elements. |
| 730 |
+ |
for (int i = 0; i < size; i++) |
| 731 |
+ |
queue[i] = s.readObject(); |
| 732 |
+ |
|
| 733 |
+ |
// Elements are guaranteed to be in "proper order", but the |
| 734 |
+ |
// spec has never explained what that might be. |
| 735 |
+ |
heapify(); |
| 736 |
+ |
} |
| 737 |
|
} |
