author | smarks |
Tue, 06 Dec 2011 10:14:02 -0800 | |
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parent 9242 | ef138d47df58 |
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/* |
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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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/* |
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* This file is available under and governed by the GNU General Public |
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* License version 2 only, as published by the Free Software Foundation. |
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* However, the following notice accompanied the original version of this |
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* file: |
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* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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package java.util.concurrent; |
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import java.util.concurrent.locks.*; |
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import java.util.*; |
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/** |
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* An unbounded {@linkplain BlockingQueue blocking queue} that uses |
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* the same ordering rules as class {@link PriorityQueue} and supplies |
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* blocking retrieval operations. While this queue is logically |
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* unbounded, attempted additions may fail due to resource exhaustion |
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* (causing {@code OutOfMemoryError}). This class does not permit |
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* {@code null} elements. A priority queue relying on {@linkplain |
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* Comparable natural ordering} also does not permit insertion of |
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* non-comparable objects (doing so results in |
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* {@code ClassCastException}). |
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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 PriorityBlockingQueue in any particular order. If you need |
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* ordered traversal, consider using |
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* {@code Arrays.sort(pq.toArray())}. Also, method {@code drainTo} |
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* can be used to <em>remove</em> some or all elements in priority |
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* order and place them in another collection. |
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* |
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* <p>Operations on this class make no guarantees about the ordering |
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* of elements with equal priority. If you need to enforce an |
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* ordering, you can define custom classes or comparators that use a |
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* secondary key to break ties in primary priority values. For |
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* example, here is a class that applies first-in-first-out |
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* tie-breaking to comparable elements. To use it, you would insert a |
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* {@code new FIFOEntry(anEntry)} instead of a plain entry object. |
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* |
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* <pre> {@code |
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* class FIFOEntry<E extends Comparable<? super E>> |
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* implements Comparable<FIFOEntry<E>> { |
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* static final AtomicLong seq = new AtomicLong(0); |
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* final long seqNum; |
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* final E entry; |
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* public FIFOEntry(E entry) { |
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* seqNum = seq.getAndIncrement(); |
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* this.entry = entry; |
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* } |
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* public E getEntry() { return entry; } |
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* public int compareTo(FIFOEntry<E> other) { |
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* int res = entry.compareTo(other.entry); |
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* if (res == 0 && other.entry != this.entry) |
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* res = (seqNum < other.seqNum ? -1 : 1); |
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* return res; |
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* } |
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* }}</pre> |
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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 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 PriorityBlockingQueue<E> extends AbstractQueue<E> |
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implements BlockingQueue<E>, java.io.Serializable { |
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private static final long serialVersionUID = 5595510919245408276L; |
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/* |
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* The implementation uses an array-based binary heap, with public |
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* operations protected with a single lock. However, allocation |
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* during resizing uses a simple spinlock (used only while not |
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* holding main lock) in order to allow takes to operate |
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* concurrently with allocation. This avoids repeated |
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* postponement of waiting consumers and consequent element |
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* build-up. The need to back away from lock during allocation |
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* makes it impossible to simply wrap delegated |
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* java.util.PriorityQueue operations within a lock, as was done |
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* in a previous version of this class. To maintain |
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* interoperability, a plain PriorityQueue is still used during |
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* serialization, which maintains compatibility at the espense of |
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* transiently doubling overhead. |
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*/ |
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/** |
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* Default array capacity. |
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*/ |
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private static final int DEFAULT_INITIAL_CAPACITY = 11; |
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/** |
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* The maximum size of array to allocate. |
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* Some VMs reserve some header words in an array. |
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* Attempts to allocate larger arrays may result in |
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* OutOfMemoryError: Requested array size exceeds VM limit |
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*/ |
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private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
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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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private transient Object[] queue; |
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/** |
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* The number of elements in the priority queue. |
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*/ |
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private transient 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 transient Comparator<? super E> comparator; |
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/** |
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* Lock used for all public operations |
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*/ |
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private final ReentrantLock lock; |
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/** |
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* Condition for blocking when empty |
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*/ |
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private final Condition notEmpty; |
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/** |
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* Spinlock for allocation, acquired via CAS. |
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*/ |
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private transient volatile int allocationSpinLock; |
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/** |
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* A plain PriorityQueue used only for serialization, |
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* to maintain compatibility with previous versions |
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* of this class. Non-null only during serialization/deserialization. |
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*/ |
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private PriorityQueue q; |
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/** |
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* Creates a {@code PriorityBlockingQueue} with the default |
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* initial capacity (11) that orders its elements according to |
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* their {@linkplain Comparable natural ordering}. |
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*/ |
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public PriorityBlockingQueue() { |
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this(DEFAULT_INITIAL_CAPACITY, null); |
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} |
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/** |
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* Creates a {@code PriorityBlockingQueue} with the specified |
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* initial 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 PriorityBlockingQueue(int initialCapacity) { |
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this(initialCapacity, null); |
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} |
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/** |
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* Creates a {@code PriorityBlockingQueue} with the specified initial |
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* capacity that orders its elements according to the specified |
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* comparator. |
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* |
|
200 |
* @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 less |
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* than 1 |
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*/ |
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public PriorityBlockingQueue(int initialCapacity, |
|
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Comparator<? super E> comparator) { |
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if (initialCapacity < 1) |
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throw new IllegalArgumentException(); |
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this.lock = new ReentrantLock(); |
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this.notEmpty = lock.newCondition(); |
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this.comparator = comparator; |
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this.queue = new Object[initialCapacity]; |
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} |
216 |
||
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/** |
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* Creates a {@code PriorityBlockingQueue} containing the elements |
2 | 219 |
* in the specified collection. If the specified collection is a |
220 |
* {@link SortedSet} or a {@link 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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public PriorityBlockingQueue(Collection<? extends E> c) { |
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this.lock = new ReentrantLock(); |
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this.notEmpty = lock.newCondition(); |
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boolean heapify = true; // true if not known to be in heap order |
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boolean screen = true; // true if must screen for nulls |
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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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heapify = false; |
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} |
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else if (c instanceof PriorityBlockingQueue<?>) { |
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PriorityBlockingQueue<? extends E> pq = |
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(PriorityBlockingQueue<? extends E>) c; |
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this.comparator = (Comparator<? super E>) pq.comparator(); |
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screen = false; |
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if (pq.getClass() == PriorityBlockingQueue.class) // exact match |
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heapify = false; |
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} |
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Object[] a = c.toArray(); |
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int n = a.length; |
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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, n, Object[].class); |
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if (screen && (n == 1 || this.comparator != null)) { |
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for (int i = 0; i < n; ++i) |
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if (a[i] == null) |
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throw new NullPointerException(); |
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} |
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this.queue = a; |
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this.size = n; |
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if (heapify) |
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heapify(); |
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} |
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266 |
|
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/** |
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* Tries to grow array to accommodate at least one more element |
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* (but normally expand by about 50%), giving up (allowing retry) |
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* on contention (which we expect to be rare). Call only while |
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* holding lock. |
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* |
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* @param array the heap array |
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* @param oldCap the length of the array |
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*/ |
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private void tryGrow(Object[] array, int oldCap) { |
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lock.unlock(); // must release and then re-acquire main lock |
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Object[] newArray = null; |
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if (allocationSpinLock == 0 && |
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UNSAFE.compareAndSwapInt(this, allocationSpinLockOffset, |
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0, 1)) { |
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try { |
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int newCap = oldCap + ((oldCap < 64) ? |
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(oldCap + 2) : // grow faster if small |
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(oldCap >> 1)); |
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286 |
if (newCap - MAX_ARRAY_SIZE > 0) { // possible overflow |
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int minCap = oldCap + 1; |
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if (minCap < 0 || minCap > MAX_ARRAY_SIZE) |
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throw new OutOfMemoryError(); |
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newCap = MAX_ARRAY_SIZE; |
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291 |
} |
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if (newCap > oldCap && queue == array) |
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newArray = new Object[newCap]; |
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294 |
} finally { |
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allocationSpinLock = 0; |
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296 |
} |
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297 |
} |
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298 |
if (newArray == null) // back off if another thread is allocating |
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299 |
Thread.yield(); |
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300 |
lock.lock(); |
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301 |
if (newArray != null && queue == array) { |
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queue = newArray; |
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303 |
System.arraycopy(array, 0, newArray, 0, oldCap); |
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} |
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305 |
} |
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306 |
|
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307 |
/** |
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* Mechanics for poll(). Call only while holding lock. |
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*/ |
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310 |
private E extract() { |
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311 |
E result; |
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int n = size - 1; |
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if (n < 0) |
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result = null; |
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315 |
else { |
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Object[] array = queue; |
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result = (E) array[0]; |
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E x = (E) array[n]; |
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array[n] = null; |
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Comparator<? super E> cmp = comparator; |
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321 |
if (cmp == null) |
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siftDownComparable(0, x, array, n); |
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323 |
else |
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324 |
siftDownUsingComparator(0, x, array, n, cmp); |
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size = n; |
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326 |
} |
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327 |
return result; |
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328 |
} |
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329 |
|
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330 |
/** |
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331 |
* Inserts item x at position k, maintaining heap invariant by |
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* promoting x up the tree until it is greater than or equal to |
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* its parent, or is the root. |
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* |
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* To simplify and speed up coercions and comparisons. the |
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* Comparable and Comparator versions are separated into different |
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* methods that are otherwise identical. (Similarly for siftDown.) |
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* These methods are static, with heap state as arguments, to |
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* simplify use in light of possible comparator exceptions. |
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diff
changeset
|
340 |
* |
f273c0d04215
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parents:
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diff
changeset
|
341 |
* @param k the position to fill |
f273c0d04215
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parents:
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diff
changeset
|
342 |
* @param x the item to insert |
f273c0d04215
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parents:
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diff
changeset
|
343 |
* @param array the heap array |
f273c0d04215
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parents:
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diff
changeset
|
344 |
* @param n heap size |
f273c0d04215
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parents:
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diff
changeset
|
345 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
346 |
private static <T> void siftUpComparable(int k, T x, Object[] array) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
347 |
Comparable<? super T> key = (Comparable<? super T>) x; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
348 |
while (k > 0) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
349 |
int parent = (k - 1) >>> 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
350 |
Object e = array[parent]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
351 |
if (key.compareTo((T) e) >= 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
352 |
break; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
353 |
array[k] = e; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
354 |
k = parent; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
355 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
356 |
array[k] = key; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
357 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
358 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
359 |
private static <T> void siftUpUsingComparator(int k, T x, Object[] array, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
360 |
Comparator<? super T> cmp) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
361 |
while (k > 0) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
362 |
int parent = (k - 1) >>> 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
363 |
Object e = array[parent]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
364 |
if (cmp.compare(x, (T) e) >= 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
365 |
break; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
366 |
array[k] = e; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
367 |
k = parent; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
368 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
369 |
array[k] = x; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
370 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
371 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
372 |
/** |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
373 |
* Inserts item x at position k, maintaining heap invariant by |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
374 |
* demoting x down the tree repeatedly until it is less than or |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
375 |
* equal to its children or is a leaf. |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
376 |
* |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
377 |
* @param k the position to fill |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
378 |
* @param x the item to insert |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
379 |
* @param array the heap array |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
380 |
* @param n heap size |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
381 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
382 |
private static <T> void siftDownComparable(int k, T x, Object[] array, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
383 |
int n) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
384 |
Comparable<? super T> key = (Comparable<? super T>)x; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
385 |
int half = n >>> 1; // loop while a non-leaf |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
386 |
while (k < half) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
387 |
int child = (k << 1) + 1; // assume left child is least |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
388 |
Object c = array[child]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
389 |
int right = child + 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
390 |
if (right < n && |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
391 |
((Comparable<? super T>) c).compareTo((T) array[right]) > 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
392 |
c = array[child = right]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
393 |
if (key.compareTo((T) c) <= 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
394 |
break; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
395 |
array[k] = c; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
396 |
k = child; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
397 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
398 |
array[k] = key; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
399 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
400 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
401 |
private static <T> void siftDownUsingComparator(int k, T x, Object[] array, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
402 |
int n, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
403 |
Comparator<? super T> cmp) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
404 |
int half = n >>> 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
405 |
while (k < half) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
406 |
int child = (k << 1) + 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
407 |
Object c = array[child]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
408 |
int right = child + 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
409 |
if (right < n && cmp.compare((T) c, (T) array[right]) > 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
410 |
c = array[child = right]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
411 |
if (cmp.compare(x, (T) c) <= 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
412 |
break; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
413 |
array[k] = c; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
414 |
k = child; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
415 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
416 |
array[k] = x; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
417 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
418 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
419 |
/** |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
420 |
* Establishes the heap invariant (described above) in the entire tree, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
421 |
* assuming nothing about the order of the elements prior to the call. |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
422 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
423 |
private void heapify() { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
424 |
Object[] array = queue; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
425 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
426 |
int half = (n >>> 1) - 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
427 |
Comparator<? super E> cmp = comparator; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
428 |
if (cmp == null) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
429 |
for (int i = half; i >= 0; i--) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
430 |
siftDownComparable(i, (E) array[i], array, n); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
431 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
432 |
else { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
433 |
for (int i = half; i >= 0; i--) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
434 |
siftDownUsingComparator(i, (E) array[i], array, n, cmp); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
435 |
} |
2 | 436 |
} |
437 |
||
438 |
/** |
|
439 |
* Inserts the specified element into this priority queue. |
|
440 |
* |
|
441 |
* @param e the element to add |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
442 |
* @return {@code true} (as specified by {@link Collection#add}) |
2 | 443 |
* @throws ClassCastException if the specified element cannot be compared |
444 |
* with elements currently in the priority queue according to the |
|
445 |
* priority queue's ordering |
|
446 |
* @throws NullPointerException if the specified element is null |
|
447 |
*/ |
|
448 |
public boolean add(E e) { |
|
449 |
return offer(e); |
|
450 |
} |
|
451 |
||
452 |
/** |
|
453 |
* Inserts the specified element into this priority queue. |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
454 |
* As the queue is unbounded, this method will never return {@code false}. |
2 | 455 |
* |
456 |
* @param e the element to add |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
457 |
* @return {@code true} (as specified by {@link Queue#offer}) |
2 | 458 |
* @throws ClassCastException if the specified element cannot be compared |
459 |
* with elements currently in the priority queue according to the |
|
460 |
* priority queue's ordering |
|
461 |
* @throws NullPointerException if the specified element is null |
|
462 |
*/ |
|
463 |
public boolean offer(E e) { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
464 |
if (e == null) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
465 |
throw new NullPointerException(); |
2 | 466 |
final ReentrantLock lock = this.lock; |
467 |
lock.lock(); |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
468 |
int n, cap; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
469 |
Object[] array; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
470 |
while ((n = size) >= (cap = (array = queue).length)) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
471 |
tryGrow(array, cap); |
2 | 472 |
try { |
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
473 |
Comparator<? super E> cmp = comparator; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
474 |
if (cmp == null) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
475 |
siftUpComparable(n, e, array); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
476 |
else |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
477 |
siftUpUsingComparator(n, e, array, cmp); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
478 |
size = n + 1; |
2 | 479 |
notEmpty.signal(); |
480 |
} finally { |
|
481 |
lock.unlock(); |
|
482 |
} |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
483 |
return true; |
2 | 484 |
} |
485 |
||
486 |
/** |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
487 |
* Inserts the specified element into this priority queue. |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
488 |
* As the queue is unbounded, this method will never block. |
2 | 489 |
* |
490 |
* @param e the element to add |
|
491 |
* @throws ClassCastException if the specified element cannot be compared |
|
492 |
* with elements currently in the priority queue according to the |
|
493 |
* priority queue's ordering |
|
494 |
* @throws NullPointerException if the specified element is null |
|
495 |
*/ |
|
496 |
public void put(E e) { |
|
497 |
offer(e); // never need to block |
|
498 |
} |
|
499 |
||
500 |
/** |
|
7976
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diff
changeset
|
501 |
* Inserts the specified element into this priority queue. |
f273c0d04215
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diff
changeset
|
502 |
* As the queue is unbounded, this method will never block or |
f273c0d04215
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parents:
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diff
changeset
|
503 |
* return {@code false}. |
2 | 504 |
* |
505 |
* @param e the element to add |
|
506 |
* @param timeout This parameter is ignored as the method never blocks |
|
507 |
* @param unit This parameter is ignored as the method never blocks |
|
7976
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diff
changeset
|
508 |
* @return {@code true} (as specified by |
f273c0d04215
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diff
changeset
|
509 |
* {@link BlockingQueue#offer(Object,long,TimeUnit) BlockingQueue.offer}) |
2 | 510 |
* @throws ClassCastException if the specified element cannot be compared |
511 |
* with elements currently in the priority queue according to the |
|
512 |
* priority queue's ordering |
|
513 |
* @throws NullPointerException if the specified element is null |
|
514 |
*/ |
|
515 |
public boolean offer(E e, long timeout, TimeUnit unit) { |
|
516 |
return offer(e); // never need to block |
|
517 |
} |
|
518 |
||
519 |
public E poll() { |
|
520 |
final ReentrantLock lock = this.lock; |
|
521 |
lock.lock(); |
|
7976
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parents:
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diff
changeset
|
522 |
E result; |
2 | 523 |
try { |
7976
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diff
changeset
|
524 |
result = extract(); |
2 | 525 |
} finally { |
526 |
lock.unlock(); |
|
527 |
} |
|
7976
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parents:
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diff
changeset
|
528 |
return result; |
2 | 529 |
} |
530 |
||
531 |
public E take() throws InterruptedException { |
|
532 |
final ReentrantLock lock = this.lock; |
|
533 |
lock.lockInterruptibly(); |
|
7976
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parents:
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diff
changeset
|
534 |
E result; |
2 | 535 |
try { |
7976
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parents:
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diff
changeset
|
536 |
while ( (result = extract()) == null) |
f273c0d04215
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parents:
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diff
changeset
|
537 |
notEmpty.await(); |
2 | 538 |
} finally { |
539 |
lock.unlock(); |
|
540 |
} |
|
7976
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parents:
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diff
changeset
|
541 |
return result; |
2 | 542 |
} |
543 |
||
544 |
public E poll(long timeout, TimeUnit unit) throws InterruptedException { |
|
545 |
long nanos = unit.toNanos(timeout); |
|
546 |
final ReentrantLock lock = this.lock; |
|
547 |
lock.lockInterruptibly(); |
|
7976
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parents:
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diff
changeset
|
548 |
E result; |
2 | 549 |
try { |
7976
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parents:
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diff
changeset
|
550 |
while ( (result = extract()) == null && nanos > 0) |
f273c0d04215
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dl
parents:
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diff
changeset
|
551 |
nanos = notEmpty.awaitNanos(nanos); |
2 | 552 |
} finally { |
553 |
lock.unlock(); |
|
554 |
} |
|
7976
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parents:
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diff
changeset
|
555 |
return result; |
2 | 556 |
} |
557 |
||
558 |
public E peek() { |
|
559 |
final ReentrantLock lock = this.lock; |
|
560 |
lock.lock(); |
|
7976
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parents:
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diff
changeset
|
561 |
E result; |
2 | 562 |
try { |
7976
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dl
parents:
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diff
changeset
|
563 |
result = size > 0 ? (E) queue[0] : null; |
f273c0d04215
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parents:
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diff
changeset
|
564 |
} finally { |
f273c0d04215
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dl
parents:
5506
diff
changeset
|
565 |
lock.unlock(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
566 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
567 |
return result; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
568 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
569 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
570 |
/** |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
571 |
* Returns the comparator used to order the elements in this queue, |
f273c0d04215
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parents:
5506
diff
changeset
|
572 |
* or {@code null} if this queue uses the {@linkplain Comparable |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
573 |
* natural ordering} of its elements. |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
574 |
* |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
575 |
* @return the comparator used to order the elements in this queue, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
576 |
* or {@code null} if this queue uses the natural |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
577 |
* ordering of its elements |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
578 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
579 |
public Comparator<? super E> comparator() { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
580 |
return comparator; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
581 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
582 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
583 |
public int size() { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
584 |
final ReentrantLock lock = this.lock; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
585 |
lock.lock(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
586 |
try { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
587 |
return size; |
2 | 588 |
} finally { |
589 |
lock.unlock(); |
|
590 |
} |
|
591 |
} |
|
592 |
||
593 |
/** |
|
7976
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7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
594 |
* Always returns {@code Integer.MAX_VALUE} because |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
595 |
* a {@code PriorityBlockingQueue} is not capacity constrained. |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
596 |
* @return {@code Integer.MAX_VALUE} always |
2 | 597 |
*/ |
7976
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7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
598 |
public int remainingCapacity() { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
599 |
return Integer.MAX_VALUE; |
2 | 600 |
} |
601 |
||
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
602 |
private int indexOf(Object o) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
603 |
if (o != null) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
604 |
Object[] array = queue; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
605 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
606 |
for (int i = 0; i < n; i++) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
607 |
if (o.equals(array[i])) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
608 |
return i; |
2 | 609 |
} |
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
610 |
return -1; |
2 | 611 |
} |
612 |
||
613 |
/** |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
614 |
* Removes the ith element from queue. |
2 | 615 |
*/ |
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
616 |
private void removeAt(int i) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
617 |
Object[] array = queue; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
618 |
int n = size - 1; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
619 |
if (n == i) // removed last element |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
620 |
array[i] = null; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
621 |
else { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
622 |
E moved = (E) array[n]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
623 |
array[n] = null; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
624 |
Comparator<? super E> cmp = comparator; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
625 |
if (cmp == null) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
626 |
siftDownComparable(i, moved, array, n); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
627 |
else |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
628 |
siftDownUsingComparator(i, moved, array, n, cmp); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
629 |
if (array[i] == moved) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
630 |
if (cmp == null) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
631 |
siftUpComparable(i, moved, array); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
632 |
else |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
633 |
siftUpUsingComparator(i, moved, array, cmp); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
634 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
635 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
636 |
size = n; |
2 | 637 |
} |
638 |
||
639 |
/** |
|
640 |
* Removes a single instance of the specified element from this queue, |
|
641 |
* if it is present. More formally, removes an element {@code e} such |
|
642 |
* that {@code o.equals(e)}, if this queue contains one or more such |
|
643 |
* elements. Returns {@code true} if and only if this queue contained |
|
644 |
* the specified element (or equivalently, if this queue changed as a |
|
645 |
* result of the call). |
|
646 |
* |
|
647 |
* @param o element to be removed from this queue, if present |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
648 |
* @return {@code true} if this queue changed as a result of the call |
2 | 649 |
*/ |
650 |
public boolean remove(Object o) { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
651 |
boolean removed = false; |
2 | 652 |
final ReentrantLock lock = this.lock; |
653 |
lock.lock(); |
|
654 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
655 |
int i = indexOf(o); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
656 |
if (i != -1) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
657 |
removeAt(i); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
658 |
removed = true; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
659 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
660 |
} finally { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
661 |
lock.unlock(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
662 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
663 |
return removed; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
664 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
665 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
666 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
667 |
/** |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
668 |
* Identity-based version for use in Itr.remove |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
669 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
670 |
private void removeEQ(Object o) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
671 |
final ReentrantLock lock = this.lock; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
672 |
lock.lock(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
673 |
try { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
674 |
Object[] array = queue; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
675 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
676 |
for (int i = 0; i < n; i++) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
677 |
if (o == array[i]) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
678 |
removeAt(i); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
679 |
break; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
680 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
681 |
} |
2 | 682 |
} finally { |
683 |
lock.unlock(); |
|
684 |
} |
|
685 |
} |
|
686 |
||
687 |
/** |
|
688 |
* Returns {@code true} if this queue contains the specified element. |
|
689 |
* More formally, returns {@code true} if and only if this queue contains |
|
690 |
* at least one element {@code e} such that {@code o.equals(e)}. |
|
691 |
* |
|
692 |
* @param o object to be checked for containment in this queue |
|
7976
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diff
changeset
|
693 |
* @return {@code true} if this queue contains the specified element |
2 | 694 |
*/ |
695 |
public boolean contains(Object o) { |
|
7976
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diff
changeset
|
696 |
int index; |
2 | 697 |
final ReentrantLock lock = this.lock; |
698 |
lock.lock(); |
|
699 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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diff
changeset
|
700 |
index = indexOf(o); |
2 | 701 |
} finally { |
702 |
lock.unlock(); |
|
703 |
} |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
5506
diff
changeset
|
704 |
return index != -1; |
2 | 705 |
} |
706 |
||
707 |
/** |
|
708 |
* Returns an array containing all of the elements in this queue. |
|
709 |
* The returned array elements are in no particular order. |
|
710 |
* |
|
711 |
* <p>The returned array will be "safe" in that no references to it are |
|
712 |
* maintained by this queue. (In other words, this method must allocate |
|
713 |
* a new array). The caller is thus free to modify the returned array. |
|
714 |
* |
|
715 |
* <p>This method acts as bridge between array-based and collection-based |
|
716 |
* APIs. |
|
717 |
* |
|
718 |
* @return an array containing all of the elements in this queue |
|
719 |
*/ |
|
720 |
public Object[] toArray() { |
|
721 |
final ReentrantLock lock = this.lock; |
|
722 |
lock.lock(); |
|
723 |
try { |
|
7976
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parents:
5506
diff
changeset
|
724 |
return Arrays.copyOf(queue, size); |
2 | 725 |
} finally { |
726 |
lock.unlock(); |
|
727 |
} |
|
728 |
} |
|
729 |
||
730 |
||
731 |
public String toString() { |
|
732 |
final ReentrantLock lock = this.lock; |
|
733 |
lock.lock(); |
|
734 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
735 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
736 |
if (n == 0) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
737 |
return "[]"; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
738 |
StringBuilder sb = new StringBuilder(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
739 |
sb.append('['); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
740 |
for (int i = 0; i < n; ++i) { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
741 |
E e = (E)queue[i]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
5506
diff
changeset
|
742 |
sb.append(e == this ? "(this Collection)" : e); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
743 |
if (i != n - 1) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
744 |
sb.append(',').append(' '); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
745 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
746 |
return sb.append(']').toString(); |
2 | 747 |
} finally { |
748 |
lock.unlock(); |
|
749 |
} |
|
750 |
} |
|
751 |
||
752 |
/** |
|
753 |
* @throws UnsupportedOperationException {@inheritDoc} |
|
754 |
* @throws ClassCastException {@inheritDoc} |
|
755 |
* @throws NullPointerException {@inheritDoc} |
|
756 |
* @throws IllegalArgumentException {@inheritDoc} |
|
757 |
*/ |
|
758 |
public int drainTo(Collection<? super E> c) { |
|
759 |
if (c == null) |
|
760 |
throw new NullPointerException(); |
|
761 |
if (c == this) |
|
762 |
throw new IllegalArgumentException(); |
|
763 |
final ReentrantLock lock = this.lock; |
|
764 |
lock.lock(); |
|
765 |
try { |
|
766 |
int n = 0; |
|
767 |
E e; |
|
7976
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dl
parents:
5506
diff
changeset
|
768 |
while ( (e = extract()) != null) { |
2 | 769 |
c.add(e); |
770 |
++n; |
|
771 |
} |
|
772 |
return n; |
|
773 |
} finally { |
|
774 |
lock.unlock(); |
|
775 |
} |
|
776 |
} |
|
777 |
||
778 |
/** |
|
779 |
* @throws UnsupportedOperationException {@inheritDoc} |
|
780 |
* @throws ClassCastException {@inheritDoc} |
|
781 |
* @throws NullPointerException {@inheritDoc} |
|
782 |
* @throws IllegalArgumentException {@inheritDoc} |
|
783 |
*/ |
|
784 |
public int drainTo(Collection<? super E> c, int maxElements) { |
|
785 |
if (c == null) |
|
786 |
throw new NullPointerException(); |
|
787 |
if (c == this) |
|
788 |
throw new IllegalArgumentException(); |
|
789 |
if (maxElements <= 0) |
|
790 |
return 0; |
|
791 |
final ReentrantLock lock = this.lock; |
|
792 |
lock.lock(); |
|
793 |
try { |
|
794 |
int n = 0; |
|
795 |
E e; |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
796 |
while (n < maxElements && (e = extract()) != null) { |
2 | 797 |
c.add(e); |
798 |
++n; |
|
799 |
} |
|
800 |
return n; |
|
801 |
} finally { |
|
802 |
lock.unlock(); |
|
803 |
} |
|
804 |
} |
|
805 |
||
806 |
/** |
|
807 |
* Atomically removes all of the elements from this queue. |
|
808 |
* The queue will be empty after this call returns. |
|
809 |
*/ |
|
810 |
public void clear() { |
|
811 |
final ReentrantLock lock = this.lock; |
|
812 |
lock.lock(); |
|
813 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
5506
diff
changeset
|
814 |
Object[] array = queue; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
815 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
816 |
size = 0; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
817 |
for (int i = 0; i < n; i++) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
818 |
array[i] = null; |
2 | 819 |
} finally { |
820 |
lock.unlock(); |
|
821 |
} |
|
822 |
} |
|
823 |
||
824 |
/** |
|
825 |
* Returns an array containing all of the elements in this queue; the |
|
826 |
* runtime type of the returned array is that of the specified array. |
|
827 |
* The returned array elements are in no particular order. |
|
828 |
* If the queue fits in the specified array, it is returned therein. |
|
829 |
* Otherwise, a new array is allocated with the runtime type of the |
|
830 |
* specified array and the size of this queue. |
|
831 |
* |
|
832 |
* <p>If this queue fits in the specified array with room to spare |
|
833 |
* (i.e., the array has more elements than this queue), the element in |
|
834 |
* the array immediately following the end of the queue is set to |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
835 |
* {@code null}. |
2 | 836 |
* |
837 |
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
|
838 |
* array-based and collection-based APIs. Further, this method allows |
|
839 |
* precise control over the runtime type of the output array, and may, |
|
840 |
* under certain circumstances, be used to save allocation costs. |
|
841 |
* |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
842 |
* <p>Suppose {@code x} is a queue known to contain only strings. |
2 | 843 |
* The following code can be used to dump the queue into a newly |
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
844 |
* allocated array of {@code String}: |
2 | 845 |
* |
846 |
* <pre> |
|
847 |
* String[] y = x.toArray(new String[0]);</pre> |
|
848 |
* |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
849 |
* Note that {@code toArray(new Object[0])} is identical in function to |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
850 |
* {@code toArray()}. |
2 | 851 |
* |
852 |
* @param a the array into which the elements of the queue are to |
|
853 |
* be stored, if it is big enough; otherwise, a new array of the |
|
854 |
* same runtime type is allocated for this purpose |
|
855 |
* @return an array containing all of the elements in this queue |
|
856 |
* @throws ArrayStoreException if the runtime type of the specified array |
|
857 |
* is not a supertype of the runtime type of every element in |
|
858 |
* this queue |
|
859 |
* @throws NullPointerException if the specified array is null |
|
860 |
*/ |
|
861 |
public <T> T[] toArray(T[] a) { |
|
862 |
final ReentrantLock lock = this.lock; |
|
863 |
lock.lock(); |
|
864 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
865 |
int n = size; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
866 |
if (a.length < n) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
867 |
// Make a new array of a's runtime type, but my contents: |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
868 |
return (T[]) Arrays.copyOf(queue, size, a.getClass()); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
869 |
System.arraycopy(queue, 0, a, 0, n); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
870 |
if (a.length > n) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
871 |
a[n] = null; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
872 |
return a; |
2 | 873 |
} finally { |
874 |
lock.unlock(); |
|
875 |
} |
|
876 |
} |
|
877 |
||
878 |
/** |
|
879 |
* Returns an iterator over the elements in this queue. The |
|
880 |
* iterator does not return the elements in any particular order. |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
881 |
* |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
882 |
* <p>The returned iterator is a "weakly consistent" iterator that |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
883 |
* will never throw {@link java.util.ConcurrentModificationException |
2 | 884 |
* ConcurrentModificationException}, and guarantees to traverse |
885 |
* elements as they existed upon construction of the iterator, and |
|
886 |
* may (but is not guaranteed to) reflect any modifications |
|
887 |
* subsequent to construction. |
|
888 |
* |
|
889 |
* @return an iterator over the elements in this queue |
|
890 |
*/ |
|
891 |
public Iterator<E> iterator() { |
|
892 |
return new Itr(toArray()); |
|
893 |
} |
|
894 |
||
895 |
/** |
|
896 |
* Snapshot iterator that works off copy of underlying q array. |
|
897 |
*/ |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
898 |
final class Itr implements Iterator<E> { |
2 | 899 |
final Object[] array; // Array of all elements |
900 |
int cursor; // index of next element to return; |
|
901 |
int lastRet; // index of last element, or -1 if no such |
|
902 |
||
903 |
Itr(Object[] array) { |
|
904 |
lastRet = -1; |
|
905 |
this.array = array; |
|
906 |
} |
|
907 |
||
908 |
public boolean hasNext() { |
|
909 |
return cursor < array.length; |
|
910 |
} |
|
911 |
||
912 |
public E next() { |
|
913 |
if (cursor >= array.length) |
|
914 |
throw new NoSuchElementException(); |
|
915 |
lastRet = cursor; |
|
916 |
return (E)array[cursor++]; |
|
917 |
} |
|
918 |
||
919 |
public void remove() { |
|
920 |
if (lastRet < 0) |
|
921 |
throw new IllegalStateException(); |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
922 |
removeEQ(array[lastRet]); |
2 | 923 |
lastRet = -1; |
924 |
} |
|
925 |
} |
|
926 |
||
927 |
/** |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
928 |
* Saves the state to a stream (that is, serializes it). For |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
929 |
* compatibility with previous version of this class, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
930 |
* elements are first copied to a java.util.PriorityQueue, |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
931 |
* which is then serialized. |
2 | 932 |
*/ |
933 |
private void writeObject(java.io.ObjectOutputStream s) |
|
934 |
throws java.io.IOException { |
|
935 |
lock.lock(); |
|
936 |
try { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
937 |
int n = size; // avoid zero capacity argument |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
938 |
q = new PriorityQueue<E>(n == 0 ? 1 : n, comparator); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
939 |
q.addAll(this); |
2 | 940 |
s.defaultWriteObject(); |
941 |
} finally { |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
942 |
q = null; |
2 | 943 |
lock.unlock(); |
944 |
} |
|
945 |
} |
|
946 |
||
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
947 |
/** |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
948 |
* Reconstitutes the {@code PriorityBlockingQueue} instance from a stream |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
949 |
* (that is, deserializes it). |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
950 |
* |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
951 |
* @param s the stream |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
952 |
*/ |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
953 |
private void readObject(java.io.ObjectInputStream s) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
954 |
throws java.io.IOException, ClassNotFoundException { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
955 |
try { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
956 |
s.defaultReadObject(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
957 |
this.queue = new Object[q.size()]; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
958 |
comparator = q.comparator(); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
959 |
addAll(q); |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
960 |
} finally { |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
961 |
q = null; |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
962 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
963 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
5506
diff
changeset
|
964 |
|
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
965 |
// Unsafe mechanics |
8544
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
966 |
private static final sun.misc.Unsafe UNSAFE; |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
967 |
private static final long allocationSpinLockOffset; |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
968 |
static { |
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7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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diff
changeset
|
969 |
try { |
8544
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
970 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
971 |
Class k = PriorityBlockingQueue.class; |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
972 |
allocationSpinLockOffset = UNSAFE.objectFieldOffset |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
973 |
(k.getDeclaredField("allocationSpinLock")); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
974 |
} catch (Exception e) { |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
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diff
changeset
|
975 |
throw new Error(e); |
7976
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7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
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diff
changeset
|
976 |
} |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
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parents:
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diff
changeset
|
977 |
} |
2 | 978 |
} |