author | psandoz |
Fri, 09 Sep 2016 14:54:29 -0700 | |
changeset 40806 | 46132d430504 |
parent 39039 | 9dea20ff2dee |
child 40817 | 4f5fb115676d |
permissions | -rw-r--r-- |
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/* |
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* Copyright (c) 2003, 2013, Oracle and/or its affiliates. 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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* 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. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.util; |
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import java.util.function.Consumer; |
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/** |
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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 {@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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* <i>capacity</i> governing the size of an array used to store the |
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* elements on the queue. It is always at least as large as the queue |
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* size. As elements are added to a priority queue, its capacity |
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* grows automatically. The details of the growth policy are not |
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* specified. |
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* |
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* <p>This class and its iterator implement all of the |
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* <em>optional</em> methods of the {@link Collection} and {@link |
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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 {@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 {@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 |
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* O(log(n)) time for the enqueuing and dequeuing 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}/../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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* @author Josh Bloch, Doug Lea |
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* @param <E> the type of elements held in this queue |
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*/ |
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public class PriorityQueue<E> extends AbstractQueue<E> |
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implements java.io.Serializable { |
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private static final long serialVersionUID = -7720805057305804111L; |
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private static final int DEFAULT_INITIAL_CAPACITY = 11; |
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/** |
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* Priority queue represented as a balanced binary heap: the two |
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* children of queue[n] are queue[2*n+1] and queue[2*(n+1)]. The |
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* priority queue is ordered by comparator, or by the elements' |
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* natural ordering, if comparator is null: For each node n in the |
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* heap and each descendant d of n, n <= d. The element with the |
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* lowest value is in queue[0], assuming the queue is nonempty. |
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*/ |
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transient Object[] queue; // non-private to simplify nested class access |
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/** |
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* The number of elements in the priority queue. |
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*/ |
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int size; |
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/** |
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* The comparator, or null if priority queue uses elements' |
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* natural ordering. |
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*/ |
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private final Comparator<? super E> comparator; |
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/** |
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* The number of times this priority queue has been |
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* <i>structurally modified</i>. See AbstractList for gory details. |
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*/ |
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transient int modCount; // non-private to simplify nested class access |
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/** |
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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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public PriorityQueue() { |
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this(DEFAULT_INITIAL_CAPACITY, null); |
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} |
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/** |
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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 {@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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* Creates a {@code PriorityQueue} with the default initial capacity and |
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* whose elements are ordered according to the specified comparator. |
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* |
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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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* @since 1.8 |
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*/ |
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public PriorityQueue(Comparator<? super E> comparator) { |
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this(DEFAULT_INITIAL_CAPACITY, comparator); |
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} |
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/** |
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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 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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Comparator<? super E> comparator) { |
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// Note: This restriction of at least one is not actually needed, |
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// but continues for 1.5 compatibility |
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if (initialCapacity < 1) |
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throw new IllegalArgumentException(); |
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this.queue = new Object[initialCapacity]; |
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this.comparator = comparator; |
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} |
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/** |
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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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* @throws ClassCastException if elements of the specified collection |
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* cannot be compared to one another according to the priority |
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* queue's ordering |
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* @throws NullPointerException if the specified collection or any |
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* of its elements are null |
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*/ |
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@SuppressWarnings("unchecked") |
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public PriorityQueue(Collection<? extends E> c) { |
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if (c instanceof SortedSet<?>) { |
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SortedSet<? extends E> ss = (SortedSet<? extends E>) c; |
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this.comparator = (Comparator<? super E>) ss.comparator(); |
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initElementsFromCollection(ss); |
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} |
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else if (c instanceof PriorityQueue<?>) { |
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PriorityQueue<? extends E> pq = (PriorityQueue<? extends E>) c; |
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this.comparator = (Comparator<? super E>) pq.comparator(); |
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initFromPriorityQueue(pq); |
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} |
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else { |
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this.comparator = null; |
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initFromCollection(c); |
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} |
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} |
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/** |
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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 {@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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@SuppressWarnings("unchecked") |
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public PriorityQueue(PriorityQueue<? extends E> c) { |
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this.comparator = (Comparator<? super E>) c.comparator(); |
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initFromPriorityQueue(c); |
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} |
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/** |
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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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* @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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* @throws NullPointerException if the specified sorted set or any |
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* of its elements are null |
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*/ |
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@SuppressWarnings("unchecked") |
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public PriorityQueue(SortedSet<? extends E> c) { |
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this.comparator = (Comparator<? super E>) c.comparator(); |
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initElementsFromCollection(c); |
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} |
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private void initFromPriorityQueue(PriorityQueue<? extends E> c) { |
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if (c.getClass() == PriorityQueue.class) { |
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this.queue = c.toArray(); |
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this.size = c.size(); |
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} else { |
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initFromCollection(c); |
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} |
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} |
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private void initElementsFromCollection(Collection<? extends E> c) { |
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Object[] a = c.toArray(); |
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// If c.toArray incorrectly doesn't return Object[], copy it. |
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if (a.getClass() != Object[].class) |
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a = Arrays.copyOf(a, a.length, Object[].class); |
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int len = a.length; |
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if (len == 1 || this.comparator != null) |
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for (Object e : a) |
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if (e == null) |
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throw new NullPointerException(); |
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this.queue = a; |
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this.size = a.length; |
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} |
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/** |
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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 |
|
272 |
*/ |
|
273 |
private void initFromCollection(Collection<? extends E> c) { |
|
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274 |
initElementsFromCollection(c); |
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|
275 |
heapify(); |
2 | 276 |
} |
277 |
||
278 |
/** |
|
5466 | 279 |
* The maximum size of array to allocate. |
280 |
* Some VMs reserve some header words in an array. |
|
281 |
* Attempts to allocate larger arrays may result in |
|
282 |
* OutOfMemoryError: Requested array size exceeds VM limit |
|
283 |
*/ |
|
284 |
private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
|
285 |
||
286 |
/** |
|
2 | 287 |
* Increases the capacity of the array. |
288 |
* |
|
289 |
* @param minCapacity the desired minimum capacity |
|
290 |
*/ |
|
291 |
private void grow(int minCapacity) { |
|
292 |
int oldCapacity = queue.length; |
|
293 |
// Double size if small; else grow by 50% |
|
5466 | 294 |
int newCapacity = oldCapacity + ((oldCapacity < 64) ? |
295 |
(oldCapacity + 2) : |
|
296 |
(oldCapacity >> 1)); |
|
297 |
// overflow-conscious code |
|
298 |
if (newCapacity - MAX_ARRAY_SIZE > 0) |
|
299 |
newCapacity = hugeCapacity(minCapacity); |
|
2 | 300 |
queue = Arrays.copyOf(queue, newCapacity); |
301 |
} |
|
302 |
||
5466 | 303 |
private static int hugeCapacity(int minCapacity) { |
304 |
if (minCapacity < 0) // overflow |
|
305 |
throw new OutOfMemoryError(); |
|
306 |
return (minCapacity > MAX_ARRAY_SIZE) ? |
|
307 |
Integer.MAX_VALUE : |
|
308 |
MAX_ARRAY_SIZE; |
|
309 |
} |
|
310 |
||
2 | 311 |
/** |
312 |
* Inserts the specified element into this priority queue. |
|
313 |
* |
|
314 |
* @return {@code true} (as specified by {@link Collection#add}) |
|
315 |
* @throws ClassCastException if the specified element cannot be |
|
316 |
* compared with elements currently in this priority queue |
|
317 |
* according to the priority queue's ordering |
|
318 |
* @throws NullPointerException if the specified element is null |
|
319 |
*/ |
|
320 |
public boolean add(E e) { |
|
321 |
return offer(e); |
|
322 |
} |
|
323 |
||
324 |
/** |
|
325 |
* Inserts the specified element into this priority queue. |
|
326 |
* |
|
327 |
* @return {@code true} (as specified by {@link Queue#offer}) |
|
328 |
* @throws ClassCastException if the specified element cannot be |
|
329 |
* compared with elements currently in this priority queue |
|
330 |
* according to the priority queue's ordering |
|
331 |
* @throws NullPointerException if the specified element is null |
|
332 |
*/ |
|
333 |
public boolean offer(E e) { |
|
334 |
if (e == null) |
|
335 |
throw new NullPointerException(); |
|
336 |
modCount++; |
|
337 |
int i = size; |
|
338 |
if (i >= queue.length) |
|
339 |
grow(i + 1); |
|
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|
340 |
siftUp(i, e); |
2 | 341 |
size = i + 1; |
342 |
return true; |
|
343 |
} |
|
344 |
||
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|
345 |
@SuppressWarnings("unchecked") |
2 | 346 |
public E peek() { |
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|
347 |
return (size == 0) ? null : (E) queue[0]; |
2 | 348 |
} |
349 |
||
350 |
private int indexOf(Object o) { |
|
351 |
if (o != null) { |
|
352 |
for (int i = 0; i < size; i++) |
|
353 |
if (o.equals(queue[i])) |
|
354 |
return i; |
|
355 |
} |
|
356 |
return -1; |
|
357 |
} |
|
358 |
||
359 |
/** |
|
360 |
* Removes a single instance of the specified element from this queue, |
|
361 |
* if it is present. More formally, removes an element {@code e} such |
|
362 |
* that {@code o.equals(e)}, if this queue contains one or more such |
|
363 |
* elements. Returns {@code true} if and only if this queue contained |
|
364 |
* the specified element (or equivalently, if this queue changed as a |
|
365 |
* result of the call). |
|
366 |
* |
|
367 |
* @param o element to be removed from this queue, if present |
|
368 |
* @return {@code true} if this queue changed as a result of the call |
|
369 |
*/ |
|
370 |
public boolean remove(Object o) { |
|
371 |
int i = indexOf(o); |
|
372 |
if (i == -1) |
|
373 |
return false; |
|
374 |
else { |
|
375 |
removeAt(i); |
|
376 |
return true; |
|
377 |
} |
|
378 |
} |
|
379 |
||
380 |
/** |
|
381 |
* Version of remove using reference equality, not equals. |
|
382 |
* Needed by iterator.remove. |
|
383 |
* |
|
384 |
* @param o element to be removed from this queue, if present |
|
385 |
* @return {@code true} if removed |
|
386 |
*/ |
|
387 |
boolean removeEq(Object o) { |
|
388 |
for (int i = 0; i < size; i++) { |
|
389 |
if (o == queue[i]) { |
|
390 |
removeAt(i); |
|
391 |
return true; |
|
392 |
} |
|
393 |
} |
|
394 |
return false; |
|
395 |
} |
|
396 |
||
397 |
/** |
|
398 |
* Returns {@code true} if this queue contains the specified element. |
|
399 |
* More formally, returns {@code true} if and only if this queue contains |
|
400 |
* at least one element {@code e} such that {@code o.equals(e)}. |
|
401 |
* |
|
402 |
* @param o object to be checked for containment in this queue |
|
403 |
* @return {@code true} if this queue contains the specified element |
|
404 |
*/ |
|
405 |
public boolean contains(Object o) { |
|
26451 | 406 |
return indexOf(o) >= 0; |
2 | 407 |
} |
408 |
||
409 |
/** |
|
410 |
* Returns an array containing all of the elements in this queue. |
|
411 |
* The elements are in no particular order. |
|
412 |
* |
|
413 |
* <p>The returned array will be "safe" in that no references to it are |
|
414 |
* maintained by this queue. (In other words, this method must allocate |
|
415 |
* a new array). The caller is thus free to modify the returned array. |
|
416 |
* |
|
417 |
* <p>This method acts as bridge between array-based and collection-based |
|
418 |
* APIs. |
|
419 |
* |
|
420 |
* @return an array containing all of the elements in this queue |
|
421 |
*/ |
|
422 |
public Object[] toArray() { |
|
423 |
return Arrays.copyOf(queue, size); |
|
424 |
} |
|
425 |
||
426 |
/** |
|
427 |
* Returns an array containing all of the elements in this queue; the |
|
428 |
* runtime type of the returned array is that of the specified array. |
|
429 |
* The returned array elements are in no particular order. |
|
430 |
* If the queue fits in the specified array, it is returned therein. |
|
431 |
* Otherwise, a new array is allocated with the runtime type of the |
|
432 |
* specified array and the size of this queue. |
|
433 |
* |
|
434 |
* <p>If the queue fits in the specified array with room to spare |
|
435 |
* (i.e., the array has more elements than the queue), the element in |
|
436 |
* the array immediately following the end of the collection is set to |
|
437 |
* {@code null}. |
|
438 |
* |
|
439 |
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
|
440 |
* array-based and collection-based APIs. Further, this method allows |
|
441 |
* precise control over the runtime type of the output array, and may, |
|
442 |
* under certain circumstances, be used to save allocation costs. |
|
443 |
* |
|
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parents:
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diff
changeset
|
444 |
* <p>Suppose {@code x} is a queue known to contain only strings. |
2 | 445 |
* The following code can be used to dump the queue into a newly |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
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parents:
13795
diff
changeset
|
446 |
* allocated array of {@code String}: |
2 | 447 |
* |
32991
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parents:
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diff
changeset
|
448 |
* <pre> {@code String[] y = x.toArray(new String[0]);}</pre> |
2 | 449 |
* |
17168
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8011426: java.util collection Spliterator implementations
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parents:
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diff
changeset
|
450 |
* Note that {@code toArray(new Object[0])} is identical in function to |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
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diff
changeset
|
451 |
* {@code toArray()}. |
2 | 452 |
* |
453 |
* @param a the array into which the elements of the queue are to |
|
454 |
* be stored, if it is big enough; otherwise, a new array of the |
|
455 |
* same runtime type is allocated for this purpose. |
|
456 |
* @return an array containing all of the elements in this queue |
|
457 |
* @throws ArrayStoreException if the runtime type of the specified array |
|
458 |
* is not a supertype of the runtime type of every element in |
|
459 |
* this queue |
|
460 |
* @throws NullPointerException if the specified array is null |
|
461 |
*/ |
|
12448 | 462 |
@SuppressWarnings("unchecked") |
2 | 463 |
public <T> T[] toArray(T[] a) { |
17168
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parents:
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changeset
|
464 |
final int size = this.size; |
2 | 465 |
if (a.length < size) |
466 |
// Make a new array of a's runtime type, but my contents: |
|
467 |
return (T[]) Arrays.copyOf(queue, size, a.getClass()); |
|
468 |
System.arraycopy(queue, 0, a, 0, size); |
|
469 |
if (a.length > size) |
|
470 |
a[size] = null; |
|
471 |
return a; |
|
472 |
} |
|
473 |
||
474 |
/** |
|
475 |
* Returns an iterator over the elements in this queue. The iterator |
|
476 |
* does not return the elements in any particular order. |
|
477 |
* |
|
478 |
* @return an iterator over the elements in this queue |
|
479 |
*/ |
|
480 |
public Iterator<E> iterator() { |
|
481 |
return new Itr(); |
|
482 |
} |
|
483 |
||
484 |
private final class Itr implements Iterator<E> { |
|
485 |
/** |
|
486 |
* Index (into queue array) of element to be returned by |
|
487 |
* subsequent call to next. |
|
488 |
*/ |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
489 |
private int cursor; |
2 | 490 |
|
491 |
/** |
|
492 |
* Index of element returned by most recent call to next, |
|
493 |
* unless that element came from the forgetMeNot list. |
|
494 |
* Set to -1 if element is deleted by a call to remove. |
|
495 |
*/ |
|
496 |
private int lastRet = -1; |
|
497 |
||
498 |
/** |
|
499 |
* A queue of elements that were moved from the unvisited portion of |
|
500 |
* the heap into the visited portion as a result of "unlucky" element |
|
501 |
* removals during the iteration. (Unlucky element removals are those |
|
502 |
* that require a siftup instead of a siftdown.) We must visit all of |
|
503 |
* the elements in this list to complete the iteration. We do this |
|
504 |
* after we've completed the "normal" iteration. |
|
505 |
* |
|
506 |
* We expect that most iterations, even those involving removals, |
|
507 |
* will not need to store elements in this field. |
|
508 |
*/ |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
509 |
private ArrayDeque<E> forgetMeNot; |
2 | 510 |
|
511 |
/** |
|
512 |
* Element returned by the most recent call to next iff that |
|
513 |
* element was drawn from the forgetMeNot list. |
|
514 |
*/ |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
515 |
private E lastRetElt; |
2 | 516 |
|
517 |
/** |
|
518 |
* The modCount value that the iterator believes that the backing |
|
519 |
* Queue should have. If this expectation is violated, the iterator |
|
520 |
* has detected concurrent modification. |
|
521 |
*/ |
|
522 |
private int expectedModCount = modCount; |
|
523 |
||
524 |
public boolean hasNext() { |
|
525 |
return cursor < size || |
|
526 |
(forgetMeNot != null && !forgetMeNot.isEmpty()); |
|
527 |
} |
|
528 |
||
12448 | 529 |
@SuppressWarnings("unchecked") |
2 | 530 |
public E next() { |
531 |
if (expectedModCount != modCount) |
|
532 |
throw new ConcurrentModificationException(); |
|
533 |
if (cursor < size) |
|
534 |
return (E) queue[lastRet = cursor++]; |
|
535 |
if (forgetMeNot != null) { |
|
536 |
lastRet = -1; |
|
537 |
lastRetElt = forgetMeNot.poll(); |
|
538 |
if (lastRetElt != null) |
|
539 |
return lastRetElt; |
|
540 |
} |
|
541 |
throw new NoSuchElementException(); |
|
542 |
} |
|
543 |
||
544 |
public void remove() { |
|
545 |
if (expectedModCount != modCount) |
|
546 |
throw new ConcurrentModificationException(); |
|
547 |
if (lastRet != -1) { |
|
548 |
E moved = PriorityQueue.this.removeAt(lastRet); |
|
549 |
lastRet = -1; |
|
550 |
if (moved == null) |
|
551 |
cursor--; |
|
552 |
else { |
|
553 |
if (forgetMeNot == null) |
|
7803
56bc97d69d93
6880112: Project Coin: Port JDK core library code to use diamond operator
smarks
parents:
5506
diff
changeset
|
554 |
forgetMeNot = new ArrayDeque<>(); |
2 | 555 |
forgetMeNot.add(moved); |
556 |
} |
|
557 |
} else if (lastRetElt != null) { |
|
558 |
PriorityQueue.this.removeEq(lastRetElt); |
|
559 |
lastRetElt = null; |
|
560 |
} else { |
|
561 |
throw new IllegalStateException(); |
|
562 |
} |
|
563 |
expectedModCount = modCount; |
|
564 |
} |
|
565 |
} |
|
566 |
||
567 |
public int size() { |
|
568 |
return size; |
|
569 |
} |
|
570 |
||
571 |
/** |
|
572 |
* Removes all of the elements from this priority queue. |
|
573 |
* The queue will be empty after this call returns. |
|
574 |
*/ |
|
575 |
public void clear() { |
|
576 |
modCount++; |
|
577 |
for (int i = 0; i < size; i++) |
|
578 |
queue[i] = null; |
|
579 |
size = 0; |
|
580 |
} |
|
581 |
||
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
582 |
@SuppressWarnings("unchecked") |
2 | 583 |
public E poll() { |
584 |
if (size == 0) |
|
585 |
return null; |
|
586 |
int s = --size; |
|
587 |
modCount++; |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
588 |
E result = (E) queue[0]; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
589 |
E x = (E) queue[s]; |
2 | 590 |
queue[s] = null; |
591 |
if (s != 0) |
|
592 |
siftDown(0, x); |
|
593 |
return result; |
|
594 |
} |
|
595 |
||
596 |
/** |
|
597 |
* Removes the ith element from queue. |
|
598 |
* |
|
599 |
* Normally this method leaves the elements at up to i-1, |
|
600 |
* inclusive, untouched. Under these circumstances, it returns |
|
601 |
* null. Occasionally, in order to maintain the heap invariant, |
|
602 |
* it must swap a later element of the list with one earlier than |
|
603 |
* i. Under these circumstances, this method returns the element |
|
604 |
* that was previously at the end of the list and is now at some |
|
605 |
* position before i. This fact is used by iterator.remove so as to |
|
606 |
* avoid missing traversing elements. |
|
607 |
*/ |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
608 |
@SuppressWarnings("unchecked") |
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
609 |
E removeAt(int i) { |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
610 |
// assert i >= 0 && i < size; |
2 | 611 |
modCount++; |
612 |
int s = --size; |
|
613 |
if (s == i) // removed last element |
|
614 |
queue[i] = null; |
|
615 |
else { |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
616 |
E moved = (E) queue[s]; |
2 | 617 |
queue[s] = null; |
618 |
siftDown(i, moved); |
|
619 |
if (queue[i] == moved) { |
|
620 |
siftUp(i, moved); |
|
621 |
if (queue[i] != moved) |
|
622 |
return moved; |
|
623 |
} |
|
624 |
} |
|
625 |
return null; |
|
626 |
} |
|
627 |
||
628 |
/** |
|
629 |
* Inserts item x at position k, maintaining heap invariant by |
|
630 |
* promoting x up the tree until it is greater than or equal to |
|
631 |
* its parent, or is the root. |
|
632 |
* |
|
633 |
* To simplify and speed up coercions and comparisons. the |
|
634 |
* Comparable and Comparator versions are separated into different |
|
635 |
* methods that are otherwise identical. (Similarly for siftDown.) |
|
636 |
* |
|
637 |
* @param k the position to fill |
|
638 |
* @param x the item to insert |
|
639 |
*/ |
|
640 |
private void siftUp(int k, E x) { |
|
641 |
if (comparator != null) |
|
642 |
siftUpUsingComparator(k, x); |
|
643 |
else |
|
644 |
siftUpComparable(k, x); |
|
645 |
} |
|
646 |
||
12448 | 647 |
@SuppressWarnings("unchecked") |
2 | 648 |
private void siftUpComparable(int k, E x) { |
649 |
Comparable<? super E> key = (Comparable<? super E>) x; |
|
650 |
while (k > 0) { |
|
651 |
int parent = (k - 1) >>> 1; |
|
652 |
Object e = queue[parent]; |
|
653 |
if (key.compareTo((E) e) >= 0) |
|
654 |
break; |
|
655 |
queue[k] = e; |
|
656 |
k = parent; |
|
657 |
} |
|
658 |
queue[k] = key; |
|
659 |
} |
|
660 |
||
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
661 |
@SuppressWarnings("unchecked") |
2 | 662 |
private void siftUpUsingComparator(int k, E x) { |
663 |
while (k > 0) { |
|
664 |
int parent = (k - 1) >>> 1; |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
665 |
Object e = queue[parent]; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
666 |
if (comparator.compare(x, (E) e) >= 0) |
2 | 667 |
break; |
668 |
queue[k] = e; |
|
669 |
k = parent; |
|
670 |
} |
|
671 |
queue[k] = x; |
|
672 |
} |
|
673 |
||
674 |
/** |
|
675 |
* Inserts item x at position k, maintaining heap invariant by |
|
676 |
* demoting x down the tree repeatedly until it is less than or |
|
677 |
* equal to its children or is a leaf. |
|
678 |
* |
|
679 |
* @param k the position to fill |
|
680 |
* @param x the item to insert |
|
681 |
*/ |
|
682 |
private void siftDown(int k, E x) { |
|
683 |
if (comparator != null) |
|
684 |
siftDownUsingComparator(k, x); |
|
685 |
else |
|
686 |
siftDownComparable(k, x); |
|
687 |
} |
|
688 |
||
12448 | 689 |
@SuppressWarnings("unchecked") |
2 | 690 |
private void siftDownComparable(int k, E x) { |
691 |
Comparable<? super E> key = (Comparable<? super E>)x; |
|
692 |
int half = size >>> 1; // loop while a non-leaf |
|
693 |
while (k < half) { |
|
694 |
int child = (k << 1) + 1; // assume left child is least |
|
695 |
Object c = queue[child]; |
|
696 |
int right = child + 1; |
|
697 |
if (right < size && |
|
698 |
((Comparable<? super E>) c).compareTo((E) queue[right]) > 0) |
|
699 |
c = queue[child = right]; |
|
700 |
if (key.compareTo((E) c) <= 0) |
|
701 |
break; |
|
702 |
queue[k] = c; |
|
703 |
k = child; |
|
704 |
} |
|
705 |
queue[k] = key; |
|
706 |
} |
|
707 |
||
12448 | 708 |
@SuppressWarnings("unchecked") |
2 | 709 |
private void siftDownUsingComparator(int k, E x) { |
710 |
int half = size >>> 1; |
|
711 |
while (k < half) { |
|
712 |
int child = (k << 1) + 1; |
|
713 |
Object c = queue[child]; |
|
714 |
int right = child + 1; |
|
715 |
if (right < size && |
|
716 |
comparator.compare((E) c, (E) queue[right]) > 0) |
|
717 |
c = queue[child = right]; |
|
718 |
if (comparator.compare(x, (E) c) <= 0) |
|
719 |
break; |
|
720 |
queue[k] = c; |
|
721 |
k = child; |
|
722 |
} |
|
723 |
queue[k] = x; |
|
724 |
} |
|
725 |
||
726 |
/** |
|
727 |
* Establishes the heap invariant (described above) in the entire tree, |
|
728 |
* assuming nothing about the order of the elements prior to the call. |
|
729 |
*/ |
|
12448 | 730 |
@SuppressWarnings("unchecked") |
2 | 731 |
private void heapify() { |
732 |
for (int i = (size >>> 1) - 1; i >= 0; i--) |
|
733 |
siftDown(i, (E) queue[i]); |
|
734 |
} |
|
735 |
||
736 |
/** |
|
737 |
* Returns the comparator used to order the elements in this |
|
738 |
* queue, or {@code null} if this queue is sorted according to |
|
739 |
* the {@linkplain Comparable natural ordering} of its elements. |
|
740 |
* |
|
741 |
* @return the comparator used to order this queue, or |
|
742 |
* {@code null} if this queue is sorted according to the |
|
743 |
* natural ordering of its elements |
|
744 |
*/ |
|
745 |
public Comparator<? super E> comparator() { |
|
746 |
return comparator; |
|
747 |
} |
|
748 |
||
749 |
/** |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
750 |
* Saves this queue to a stream (that is, serializes it). |
2 | 751 |
* |
752 |
* @serialData The length of the array backing the instance is |
|
753 |
* emitted (int), followed by all of its elements |
|
754 |
* (each an {@code Object}) in the proper order. |
|
755 |
* @param s the stream |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
756 |
* @throws java.io.IOException if an I/O error occurs |
2 | 757 |
*/ |
758 |
private void writeObject(java.io.ObjectOutputStream s) |
|
17168
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8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
759 |
throws java.io.IOException { |
2 | 760 |
// Write out element count, and any hidden stuff |
761 |
s.defaultWriteObject(); |
|
762 |
||
763 |
// Write out array length, for compatibility with 1.5 version |
|
764 |
s.writeInt(Math.max(2, size + 1)); |
|
765 |
||
766 |
// Write out all elements in the "proper order". |
|
767 |
for (int i = 0; i < size; i++) |
|
768 |
s.writeObject(queue[i]); |
|
769 |
} |
|
770 |
||
771 |
/** |
|
772 |
* Reconstitutes the {@code PriorityQueue} instance from a stream |
|
773 |
* (that is, deserializes it). |
|
774 |
* |
|
775 |
* @param s the stream |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
776 |
* @throws ClassNotFoundException if the class of a serialized object |
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
777 |
* could not be found |
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
778 |
* @throws java.io.IOException if an I/O error occurs |
2 | 779 |
*/ |
780 |
private void readObject(java.io.ObjectInputStream s) |
|
781 |
throws java.io.IOException, ClassNotFoundException { |
|
782 |
// Read in size, and any hidden stuff |
|
783 |
s.defaultReadObject(); |
|
784 |
||
785 |
// Read in (and discard) array length |
|
786 |
s.readInt(); |
|
787 |
||
788 |
queue = new Object[size]; |
|
789 |
||
790 |
// Read in all elements. |
|
791 |
for (int i = 0; i < size; i++) |
|
792 |
queue[i] = s.readObject(); |
|
793 |
||
794 |
// Elements are guaranteed to be in "proper order", but the |
|
795 |
// spec has never explained what that might be. |
|
796 |
heapify(); |
|
797 |
} |
|
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
798 |
|
19435
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
799 |
/** |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
800 |
* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em> |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
801 |
* and <em>fail-fast</em> {@link Spliterator} over the elements in this |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
802 |
* queue. |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
803 |
* |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
804 |
* <p>The {@code Spliterator} reports {@link Spliterator#SIZED}, |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
805 |
* {@link Spliterator#SUBSIZED}, and {@link Spliterator#NONNULL}. |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
806 |
* Overriding implementations should document the reporting of additional |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
807 |
* characteristic values. |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
808 |
* |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
809 |
* @return a {@code Spliterator} over the elements in this queue |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
810 |
* @since 1.8 |
9d7530ff42cb
8014824: Document Spliterator characteristics and binding policy of java util collection impls
psandoz
parents:
19059
diff
changeset
|
811 |
*/ |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
812 |
public final Spliterator<E> spliterator() { |
22078
bdec5d53e98c
8030851: Update code in java.util to use newer language features
psandoz
parents:
21278
diff
changeset
|
813 |
return new PriorityQueueSpliterator<>(this, 0, -1, 0); |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
814 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
815 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
816 |
static final class PriorityQueueSpliterator<E> implements Spliterator<E> { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
817 |
/* |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
818 |
* This is very similar to ArrayList Spliterator, except for |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
819 |
* extra null checks. |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
820 |
*/ |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
821 |
private final PriorityQueue<E> pq; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
822 |
private int index; // current index, modified on advance/split |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
823 |
private int fence; // -1 until first use |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
824 |
private int expectedModCount; // initialized when fence set |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
825 |
|
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
826 |
/** Creates new spliterator covering the given range. */ |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
827 |
PriorityQueueSpliterator(PriorityQueue<E> pq, int origin, int fence, |
32991
b27c76b82713
8134853: Bulk integration of java.util.concurrent classes
dl
parents:
26451
diff
changeset
|
828 |
int expectedModCount) { |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
829 |
this.pq = pq; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
830 |
this.index = origin; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
831 |
this.fence = fence; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
832 |
this.expectedModCount = expectedModCount; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
833 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
834 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
835 |
private int getFence() { // initialize fence to size on first use |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
836 |
int hi; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
837 |
if ((hi = fence) < 0) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
838 |
expectedModCount = pq.modCount; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
839 |
hi = fence = pq.size; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
840 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
841 |
return hi; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
842 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
843 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
844 |
public PriorityQueueSpliterator<E> trySplit() { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
845 |
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
846 |
return (lo >= mid) ? null : |
22078
bdec5d53e98c
8030851: Update code in java.util to use newer language features
psandoz
parents:
21278
diff
changeset
|
847 |
new PriorityQueueSpliterator<>(pq, lo, index = mid, |
bdec5d53e98c
8030851: Update code in java.util to use newer language features
psandoz
parents:
21278
diff
changeset
|
848 |
expectedModCount); |
17168
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
849 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
850 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
851 |
@SuppressWarnings("unchecked") |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
852 |
public void forEachRemaining(Consumer<? super E> action) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
853 |
int i, hi, mc; // hoist accesses and checks from loop |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
854 |
PriorityQueue<E> q; Object[] a; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
855 |
if (action == null) |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
856 |
throw new NullPointerException(); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
857 |
if ((q = pq) != null && (a = q.queue) != null) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
858 |
if ((hi = fence) < 0) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
859 |
mc = q.modCount; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
860 |
hi = q.size; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
861 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
862 |
else |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
863 |
mc = expectedModCount; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
864 |
if ((i = index) >= 0 && (index = hi) <= a.length) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
865 |
for (E e;; ++i) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
866 |
if (i < hi) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
867 |
if ((e = (E) a[i]) == null) // must be CME |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
868 |
break; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
869 |
action.accept(e); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
870 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
871 |
else if (q.modCount != mc) |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
872 |
break; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
873 |
else |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
874 |
return; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
875 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
876 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
877 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
878 |
throw new ConcurrentModificationException(); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
879 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
880 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
881 |
public boolean tryAdvance(Consumer<? super E> action) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
882 |
if (action == null) |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
883 |
throw new NullPointerException(); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
884 |
int hi = getFence(), lo = index; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
885 |
if (lo >= 0 && lo < hi) { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
886 |
index = lo + 1; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
887 |
@SuppressWarnings("unchecked") E e = (E)pq.queue[lo]; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
888 |
if (e == null) |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
889 |
throw new ConcurrentModificationException(); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
890 |
action.accept(e); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
891 |
if (pq.modCount != expectedModCount) |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
892 |
throw new ConcurrentModificationException(); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
893 |
return true; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
894 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
895 |
return false; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
896 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
897 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
898 |
public long estimateSize() { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
899 |
return (long) (getFence() - index); |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
900 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
901 |
|
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
902 |
public int characteristics() { |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
903 |
return Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.NONNULL; |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
904 |
} |
b7d3500f2516
8011426: java.util collection Spliterator implementations
psandoz
parents:
13795
diff
changeset
|
905 |
} |
2 | 906 |
} |