author | smarks |
Tue, 06 Dec 2011 10:14:02 -0800 | |
changeset 11139 | db0c2ff5e1ea |
parent 9504 | a61398ab96e0 |
child 11279 | d9dab5ec5044 |
permissions | -rw-r--r-- |
2 | 1 |
/* |
9035
1255eb81cc2f
7033660: Update copyright year to 2011 on any files changed in 2011
ohair
parents:
8544
diff
changeset
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* Copyright (c) 2003, 2011, 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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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group. Adapted and released, under explicit permission, |
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* from JDK ArrayList.java which carries the following copyright: |
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* |
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* Copyright 1997 by Sun Microsystems, Inc., |
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* 901 San Antonio Road, Palo Alto, California, 94303, U.S.A. |
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* All rights reserved. |
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*/ |
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package java.util.concurrent; |
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import java.util.*; |
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import java.util.concurrent.locks.*; |
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import sun.misc.Unsafe; |
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/** |
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* A thread-safe variant of {@link java.util.ArrayList} in which all mutative |
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* operations (<tt>add</tt>, <tt>set</tt>, and so on) are implemented by |
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* making a fresh copy of the underlying array. |
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* |
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* <p> This is ordinarily too costly, but may be <em>more</em> efficient |
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* than alternatives when traversal operations vastly outnumber |
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* mutations, and is useful when you cannot or don't want to |
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* synchronize traversals, yet need to preclude interference among |
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* concurrent threads. The "snapshot" style iterator method uses a |
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* reference to the state of the array at the point that the iterator |
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* was created. This array never changes during the lifetime of the |
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* iterator, so interference is impossible and the iterator is |
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* guaranteed not to throw <tt>ConcurrentModificationException</tt>. |
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* The iterator will not reflect additions, removals, or changes to |
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* the list since the iterator was created. Element-changing |
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* operations on iterators themselves (<tt>remove</tt>, <tt>set</tt>, and |
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* <tt>add</tt>) are not supported. These methods throw |
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* <tt>UnsupportedOperationException</tt>. |
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* |
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* <p>All elements are permitted, including <tt>null</tt>. |
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* |
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* <p>Memory consistency effects: As with other concurrent |
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* collections, actions in a thread prior to placing an object into a |
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* {@code CopyOnWriteArrayList} |
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* <a href="package-summary.html#MemoryVisibility"><i>happen-before</i></a> |
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* actions subsequent to the access or removal of that element from |
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* the {@code CopyOnWriteArrayList} in another thread. |
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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 CopyOnWriteArrayList<E> |
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implements List<E>, RandomAccess, Cloneable, java.io.Serializable { |
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private static final long serialVersionUID = 8673264195747942595L; |
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/** The lock protecting all mutators */ |
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transient final ReentrantLock lock = new ReentrantLock(); |
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/** The array, accessed only via getArray/setArray. */ |
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private volatile transient Object[] array; |
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/** |
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* Gets the array. Non-private so as to also be accessible |
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* from CopyOnWriteArraySet class. |
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*/ |
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final Object[] getArray() { |
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return array; |
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} |
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/** |
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* Sets the array. |
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*/ |
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final void setArray(Object[] a) { |
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array = a; |
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} |
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/** |
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* Creates an empty list. |
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*/ |
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public CopyOnWriteArrayList() { |
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setArray(new Object[0]); |
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} |
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/** |
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* Creates a list containing the elements of the specified |
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* collection, in the order they are returned by the collection's |
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* iterator. |
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* |
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* @param c the collection of initially held elements |
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* @throws NullPointerException if the specified collection is null |
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*/ |
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public CopyOnWriteArrayList(Collection<? extends E> c) { |
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Object[] elements = c.toArray(); |
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// c.toArray might (incorrectly) not return Object[] (see 6260652) |
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if (elements.getClass() != Object[].class) |
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elements = Arrays.copyOf(elements, elements.length, Object[].class); |
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setArray(elements); |
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} |
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/** |
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* Creates a list holding a copy of the given array. |
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* |
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* @param toCopyIn the array (a copy of this array is used as the |
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* internal array) |
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* @throws NullPointerException if the specified array is null |
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*/ |
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public CopyOnWriteArrayList(E[] toCopyIn) { |
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setArray(Arrays.copyOf(toCopyIn, toCopyIn.length, Object[].class)); |
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} |
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/** |
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* Returns the number of elements in this list. |
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* |
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* @return the number of elements in this list |
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*/ |
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public int size() { |
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return getArray().length; |
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} |
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/** |
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* Returns <tt>true</tt> if this list contains no elements. |
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* |
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* @return <tt>true</tt> if this list contains no elements |
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*/ |
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public boolean isEmpty() { |
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return size() == 0; |
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} |
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/** |
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* Test for equality, coping with nulls. |
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*/ |
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private static boolean eq(Object o1, Object o2) { |
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return (o1 == null ? o2 == null : o1.equals(o2)); |
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} |
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||
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/** |
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* static version of indexOf, to allow repeated calls without |
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* needing to re-acquire array each time. |
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* @param o element to search for |
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* @param elements the array |
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* @param index first index to search |
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* @param fence one past last index to search |
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* @return index of element, or -1 if absent |
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*/ |
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private static int indexOf(Object o, Object[] elements, |
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int index, int fence) { |
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if (o == null) { |
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for (int i = index; i < fence; i++) |
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if (elements[i] == null) |
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return i; |
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} else { |
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for (int i = index; i < fence; i++) |
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if (o.equals(elements[i])) |
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return i; |
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} |
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return -1; |
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} |
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||
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/** |
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* static version of lastIndexOf. |
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* @param o element to search for |
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* @param elements the array |
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* @param index first index to search |
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* @return index of element, or -1 if absent |
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*/ |
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private static int lastIndexOf(Object o, Object[] elements, int index) { |
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if (o == null) { |
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for (int i = index; i >= 0; i--) |
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if (elements[i] == null) |
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return i; |
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} else { |
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for (int i = index; i >= 0; i--) |
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if (o.equals(elements[i])) |
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return i; |
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} |
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return -1; |
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} |
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/** |
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* Returns <tt>true</tt> if this list contains the specified element. |
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* More formally, returns <tt>true</tt> if and only if this list contains |
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* at least one element <tt>e</tt> such that |
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* <tt>(o==null ? e==null : o.equals(e))</tt>. |
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* |
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* @param o element whose presence in this list is to be tested |
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* @return <tt>true</tt> if this list contains the specified element |
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*/ |
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public boolean contains(Object o) { |
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Object[] elements = getArray(); |
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return indexOf(o, elements, 0, elements.length) >= 0; |
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} |
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/** |
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* {@inheritDoc} |
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*/ |
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public int indexOf(Object o) { |
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Object[] elements = getArray(); |
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return indexOf(o, elements, 0, elements.length); |
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} |
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227 |
/** |
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* Returns the index of the first occurrence of the specified element in |
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* this list, searching forwards from <tt>index</tt>, or returns -1 if |
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* the element is not found. |
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* More formally, returns the lowest index <tt>i</tt> such that |
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* <tt>(i >= index && (e==null ? get(i)==null : e.equals(get(i))))</tt>, |
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* or -1 if there is no such index. |
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* |
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* @param e element to search for |
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* @param index index to start searching from |
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* @return the index of the first occurrence of the element in |
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* this list at position <tt>index</tt> or later in the list; |
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* <tt>-1</tt> if the element is not found. |
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* @throws IndexOutOfBoundsException if the specified index is negative |
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*/ |
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242 |
public int indexOf(E e, int index) { |
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Object[] elements = getArray(); |
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return indexOf(e, elements, index, elements.length); |
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} |
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246 |
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247 |
/** |
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248 |
* {@inheritDoc} |
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*/ |
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250 |
public int lastIndexOf(Object o) { |
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251 |
Object[] elements = getArray(); |
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return lastIndexOf(o, elements, elements.length - 1); |
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253 |
} |
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254 |
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255 |
/** |
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256 |
* Returns the index of the last occurrence of the specified element in |
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257 |
* this list, searching backwards from <tt>index</tt>, or returns -1 if |
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258 |
* the element is not found. |
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259 |
* More formally, returns the highest index <tt>i</tt> such that |
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260 |
* <tt>(i <= index && (e==null ? get(i)==null : e.equals(get(i))))</tt>, |
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261 |
* or -1 if there is no such index. |
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262 |
* |
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263 |
* @param e element to search for |
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264 |
* @param index index to start searching backwards from |
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265 |
* @return the index of the last occurrence of the element at position |
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266 |
* less than or equal to <tt>index</tt> in this list; |
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267 |
* -1 if the element is not found. |
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268 |
* @throws IndexOutOfBoundsException if the specified index is greater |
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269 |
* than or equal to the current size of this list |
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270 |
*/ |
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271 |
public int lastIndexOf(E e, int index) { |
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272 |
Object[] elements = getArray(); |
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273 |
return lastIndexOf(e, elements, index); |
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274 |
} |
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275 |
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276 |
/** |
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277 |
* Returns a shallow copy of this list. (The elements themselves |
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278 |
* are not copied.) |
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279 |
* |
|
280 |
* @return a clone of this list |
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281 |
*/ |
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282 |
public Object clone() { |
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283 |
try { |
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284 |
CopyOnWriteArrayList c = (CopyOnWriteArrayList)(super.clone()); |
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c.resetLock(); |
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return c; |
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287 |
} catch (CloneNotSupportedException e) { |
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288 |
// this shouldn't happen, since we are Cloneable |
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289 |
throw new InternalError(); |
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290 |
} |
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291 |
} |
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292 |
||
293 |
/** |
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294 |
* Returns an array containing all of the elements in this list |
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295 |
* in proper sequence (from first to last element). |
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296 |
* |
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297 |
* <p>The returned array will be "safe" in that no references to it are |
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298 |
* maintained by this list. (In other words, this method must allocate |
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299 |
* a new array). The caller is thus free to modify the returned array. |
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300 |
* |
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301 |
* <p>This method acts as bridge between array-based and collection-based |
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302 |
* APIs. |
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303 |
* |
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304 |
* @return an array containing all the elements in this list |
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305 |
*/ |
|
306 |
public Object[] toArray() { |
|
307 |
Object[] elements = getArray(); |
|
308 |
return Arrays.copyOf(elements, elements.length); |
|
309 |
} |
|
310 |
||
311 |
/** |
|
312 |
* Returns an array containing all of the elements in this list in |
|
313 |
* proper sequence (from first to last element); the runtime type of |
|
314 |
* the returned array is that of the specified array. If the list fits |
|
315 |
* in the specified array, it is returned therein. Otherwise, a new |
|
316 |
* array is allocated with the runtime type of the specified array and |
|
317 |
* the size of this list. |
|
318 |
* |
|
319 |
* <p>If this list fits in the specified array with room to spare |
|
320 |
* (i.e., the array has more elements than this list), the element in |
|
321 |
* the array immediately following the end of the list is set to |
|
322 |
* <tt>null</tt>. (This is useful in determining the length of this |
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323 |
* list <i>only</i> if the caller knows that this list does not contain |
|
324 |
* any null elements.) |
|
325 |
* |
|
326 |
* <p>Like the {@link #toArray()} method, this method acts as bridge between |
|
327 |
* array-based and collection-based APIs. Further, this method allows |
|
328 |
* precise control over the runtime type of the output array, and may, |
|
329 |
* under certain circumstances, be used to save allocation costs. |
|
330 |
* |
|
331 |
* <p>Suppose <tt>x</tt> is a list known to contain only strings. |
|
332 |
* The following code can be used to dump the list into a newly |
|
333 |
* allocated array of <tt>String</tt>: |
|
334 |
* |
|
335 |
* <pre> |
|
336 |
* String[] y = x.toArray(new String[0]);</pre> |
|
337 |
* |
|
338 |
* Note that <tt>toArray(new Object[0])</tt> is identical in function to |
|
339 |
* <tt>toArray()</tt>. |
|
340 |
* |
|
341 |
* @param a the array into which the elements of the list are to |
|
342 |
* be stored, if it is big enough; otherwise, a new array of the |
|
343 |
* same runtime type is allocated for this purpose. |
|
344 |
* @return an array containing all the elements in this list |
|
345 |
* @throws ArrayStoreException if the runtime type of the specified array |
|
346 |
* is not a supertype of the runtime type of every element in |
|
347 |
* this list |
|
348 |
* @throws NullPointerException if the specified array is null |
|
349 |
*/ |
|
350 |
@SuppressWarnings("unchecked") |
|
351 |
public <T> T[] toArray(T a[]) { |
|
352 |
Object[] elements = getArray(); |
|
353 |
int len = elements.length; |
|
354 |
if (a.length < len) |
|
355 |
return (T[]) Arrays.copyOf(elements, len, a.getClass()); |
|
356 |
else { |
|
357 |
System.arraycopy(elements, 0, a, 0, len); |
|
358 |
if (a.length > len) |
|
359 |
a[len] = null; |
|
360 |
return a; |
|
361 |
} |
|
362 |
} |
|
363 |
||
364 |
// Positional Access Operations |
|
365 |
||
366 |
@SuppressWarnings("unchecked") |
|
367 |
private E get(Object[] a, int index) { |
|
368 |
return (E) a[index]; |
|
369 |
} |
|
370 |
||
371 |
/** |
|
372 |
* {@inheritDoc} |
|
373 |
* |
|
374 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
375 |
*/ |
|
376 |
public E get(int index) { |
|
377 |
return get(getArray(), index); |
|
378 |
} |
|
379 |
||
380 |
/** |
|
381 |
* Replaces the element at the specified position in this list with the |
|
382 |
* specified element. |
|
383 |
* |
|
384 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
385 |
*/ |
|
386 |
public E set(int index, E element) { |
|
387 |
final ReentrantLock lock = this.lock; |
|
388 |
lock.lock(); |
|
389 |
try { |
|
390 |
Object[] elements = getArray(); |
|
391 |
E oldValue = get(elements, index); |
|
392 |
||
393 |
if (oldValue != element) { |
|
394 |
int len = elements.length; |
|
395 |
Object[] newElements = Arrays.copyOf(elements, len); |
|
396 |
newElements[index] = element; |
|
397 |
setArray(newElements); |
|
398 |
} else { |
|
399 |
// Not quite a no-op; ensures volatile write semantics |
|
400 |
setArray(elements); |
|
401 |
} |
|
402 |
return oldValue; |
|
403 |
} finally { |
|
404 |
lock.unlock(); |
|
405 |
} |
|
406 |
} |
|
407 |
||
408 |
/** |
|
409 |
* Appends the specified element to the end of this list. |
|
410 |
* |
|
411 |
* @param e element to be appended to this list |
|
412 |
* @return <tt>true</tt> (as specified by {@link Collection#add}) |
|
413 |
*/ |
|
414 |
public boolean add(E e) { |
|
415 |
final ReentrantLock lock = this.lock; |
|
416 |
lock.lock(); |
|
417 |
try { |
|
418 |
Object[] elements = getArray(); |
|
419 |
int len = elements.length; |
|
420 |
Object[] newElements = Arrays.copyOf(elements, len + 1); |
|
421 |
newElements[len] = e; |
|
422 |
setArray(newElements); |
|
423 |
return true; |
|
424 |
} finally { |
|
425 |
lock.unlock(); |
|
426 |
} |
|
427 |
} |
|
428 |
||
429 |
/** |
|
430 |
* Inserts the specified element at the specified position in this |
|
431 |
* list. Shifts the element currently at that position (if any) and |
|
432 |
* any subsequent elements to the right (adds one to their indices). |
|
433 |
* |
|
434 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
435 |
*/ |
|
436 |
public void add(int index, E element) { |
|
437 |
final ReentrantLock lock = this.lock; |
|
438 |
lock.lock(); |
|
439 |
try { |
|
440 |
Object[] elements = getArray(); |
|
441 |
int len = elements.length; |
|
442 |
if (index > len || index < 0) |
|
443 |
throw new IndexOutOfBoundsException("Index: "+index+ |
|
444 |
", Size: "+len); |
|
445 |
Object[] newElements; |
|
446 |
int numMoved = len - index; |
|
447 |
if (numMoved == 0) |
|
448 |
newElements = Arrays.copyOf(elements, len + 1); |
|
449 |
else { |
|
450 |
newElements = new Object[len + 1]; |
|
451 |
System.arraycopy(elements, 0, newElements, 0, index); |
|
452 |
System.arraycopy(elements, index, newElements, index + 1, |
|
453 |
numMoved); |
|
454 |
} |
|
455 |
newElements[index] = element; |
|
456 |
setArray(newElements); |
|
457 |
} finally { |
|
458 |
lock.unlock(); |
|
459 |
} |
|
460 |
} |
|
461 |
||
462 |
/** |
|
463 |
* Removes the element at the specified position in this list. |
|
464 |
* Shifts any subsequent elements to the left (subtracts one from their |
|
465 |
* indices). Returns the element that was removed from the list. |
|
466 |
* |
|
467 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
468 |
*/ |
|
469 |
public E remove(int index) { |
|
470 |
final ReentrantLock lock = this.lock; |
|
471 |
lock.lock(); |
|
472 |
try { |
|
473 |
Object[] elements = getArray(); |
|
474 |
int len = elements.length; |
|
475 |
E oldValue = get(elements, index); |
|
476 |
int numMoved = len - index - 1; |
|
477 |
if (numMoved == 0) |
|
478 |
setArray(Arrays.copyOf(elements, len - 1)); |
|
479 |
else { |
|
480 |
Object[] newElements = new Object[len - 1]; |
|
481 |
System.arraycopy(elements, 0, newElements, 0, index); |
|
482 |
System.arraycopy(elements, index + 1, newElements, index, |
|
483 |
numMoved); |
|
484 |
setArray(newElements); |
|
485 |
} |
|
486 |
return oldValue; |
|
487 |
} finally { |
|
488 |
lock.unlock(); |
|
489 |
} |
|
490 |
} |
|
491 |
||
492 |
/** |
|
493 |
* Removes the first occurrence of the specified element from this list, |
|
494 |
* if it is present. If this list does not contain the element, it is |
|
495 |
* unchanged. More formally, removes the element with the lowest index |
|
496 |
* <tt>i</tt> such that |
|
497 |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> |
|
498 |
* (if such an element exists). Returns <tt>true</tt> if this list |
|
499 |
* contained the specified element (or equivalently, if this list |
|
500 |
* changed as a result of the call). |
|
501 |
* |
|
502 |
* @param o element to be removed from this list, if present |
|
503 |
* @return <tt>true</tt> if this list contained the specified element |
|
504 |
*/ |
|
505 |
public boolean remove(Object o) { |
|
506 |
final ReentrantLock lock = this.lock; |
|
507 |
lock.lock(); |
|
508 |
try { |
|
509 |
Object[] elements = getArray(); |
|
510 |
int len = elements.length; |
|
511 |
if (len != 0) { |
|
512 |
// Copy while searching for element to remove |
|
513 |
// This wins in the normal case of element being present |
|
514 |
int newlen = len - 1; |
|
515 |
Object[] newElements = new Object[newlen]; |
|
516 |
||
517 |
for (int i = 0; i < newlen; ++i) { |
|
518 |
if (eq(o, elements[i])) { |
|
519 |
// found one; copy remaining and exit |
|
520 |
for (int k = i + 1; k < len; ++k) |
|
521 |
newElements[k-1] = elements[k]; |
|
522 |
setArray(newElements); |
|
523 |
return true; |
|
524 |
} else |
|
525 |
newElements[i] = elements[i]; |
|
526 |
} |
|
527 |
||
528 |
// special handling for last cell |
|
529 |
if (eq(o, elements[newlen])) { |
|
530 |
setArray(newElements); |
|
531 |
return true; |
|
532 |
} |
|
533 |
} |
|
534 |
return false; |
|
535 |
} finally { |
|
536 |
lock.unlock(); |
|
537 |
} |
|
538 |
} |
|
539 |
||
540 |
/** |
|
541 |
* Removes from this list all of the elements whose index is between |
|
542 |
* <tt>fromIndex</tt>, inclusive, and <tt>toIndex</tt>, exclusive. |
|
543 |
* Shifts any succeeding elements to the left (reduces their index). |
|
544 |
* This call shortens the list by <tt>(toIndex - fromIndex)</tt> elements. |
|
545 |
* (If <tt>toIndex==fromIndex</tt>, this operation has no effect.) |
|
546 |
* |
|
547 |
* @param fromIndex index of first element to be removed |
|
548 |
* @param toIndex index after last element to be removed |
|
549 |
* @throws IndexOutOfBoundsException if fromIndex or toIndex out of range |
|
7518 | 550 |
* ({@code{fromIndex < 0 || toIndex > size() || toIndex < fromIndex}) |
2 | 551 |
*/ |
552 |
private void removeRange(int fromIndex, int toIndex) { |
|
553 |
final ReentrantLock lock = this.lock; |
|
554 |
lock.lock(); |
|
555 |
try { |
|
556 |
Object[] elements = getArray(); |
|
557 |
int len = elements.length; |
|
558 |
||
559 |
if (fromIndex < 0 || toIndex > len || toIndex < fromIndex) |
|
560 |
throw new IndexOutOfBoundsException(); |
|
561 |
int newlen = len - (toIndex - fromIndex); |
|
562 |
int numMoved = len - toIndex; |
|
563 |
if (numMoved == 0) |
|
564 |
setArray(Arrays.copyOf(elements, newlen)); |
|
565 |
else { |
|
566 |
Object[] newElements = new Object[newlen]; |
|
567 |
System.arraycopy(elements, 0, newElements, 0, fromIndex); |
|
568 |
System.arraycopy(elements, toIndex, newElements, |
|
569 |
fromIndex, numMoved); |
|
570 |
setArray(newElements); |
|
571 |
} |
|
572 |
} finally { |
|
573 |
lock.unlock(); |
|
574 |
} |
|
575 |
} |
|
576 |
||
577 |
/** |
|
578 |
* Append the element if not present. |
|
579 |
* |
|
580 |
* @param e element to be added to this list, if absent |
|
581 |
* @return <tt>true</tt> if the element was added |
|
582 |
*/ |
|
583 |
public boolean addIfAbsent(E e) { |
|
584 |
final ReentrantLock lock = this.lock; |
|
585 |
lock.lock(); |
|
586 |
try { |
|
587 |
// Copy while checking if already present. |
|
588 |
// This wins in the most common case where it is not present |
|
589 |
Object[] elements = getArray(); |
|
590 |
int len = elements.length; |
|
591 |
Object[] newElements = new Object[len + 1]; |
|
592 |
for (int i = 0; i < len; ++i) { |
|
593 |
if (eq(e, elements[i])) |
|
594 |
return false; // exit, throwing away copy |
|
595 |
else |
|
596 |
newElements[i] = elements[i]; |
|
597 |
} |
|
598 |
newElements[len] = e; |
|
599 |
setArray(newElements); |
|
600 |
return true; |
|
601 |
} finally { |
|
602 |
lock.unlock(); |
|
603 |
} |
|
604 |
} |
|
605 |
||
606 |
/** |
|
607 |
* Returns <tt>true</tt> if this list contains all of the elements of the |
|
608 |
* specified collection. |
|
609 |
* |
|
610 |
* @param c collection to be checked for containment in this list |
|
611 |
* @return <tt>true</tt> if this list contains all of the elements of the |
|
612 |
* specified collection |
|
613 |
* @throws NullPointerException if the specified collection is null |
|
614 |
* @see #contains(Object) |
|
615 |
*/ |
|
616 |
public boolean containsAll(Collection<?> c) { |
|
617 |
Object[] elements = getArray(); |
|
618 |
int len = elements.length; |
|
619 |
for (Object e : c) { |
|
620 |
if (indexOf(e, elements, 0, len) < 0) |
|
621 |
return false; |
|
622 |
} |
|
623 |
return true; |
|
624 |
} |
|
625 |
||
626 |
/** |
|
627 |
* Removes from this list all of its elements that are contained in |
|
628 |
* the specified collection. This is a particularly expensive operation |
|
629 |
* in this class because of the need for an internal temporary array. |
|
630 |
* |
|
631 |
* @param c collection containing elements to be removed from this list |
|
632 |
* @return <tt>true</tt> if this list changed as a result of the call |
|
633 |
* @throws ClassCastException if the class of an element of this list |
|
9504 | 634 |
* is incompatible with the specified collection |
635 |
* (<a href="../Collection.html#optional-restrictions">optional</a>) |
|
2 | 636 |
* @throws NullPointerException if this list contains a null element and the |
9504 | 637 |
* specified collection does not permit null elements |
638 |
* (<a href="../Collection.html#optional-restrictions">optional</a>), |
|
2 | 639 |
* or if the specified collection is null |
640 |
* @see #remove(Object) |
|
641 |
*/ |
|
642 |
public boolean removeAll(Collection<?> c) { |
|
643 |
final ReentrantLock lock = this.lock; |
|
644 |
lock.lock(); |
|
645 |
try { |
|
646 |
Object[] elements = getArray(); |
|
647 |
int len = elements.length; |
|
648 |
if (len != 0) { |
|
649 |
// temp array holds those elements we know we want to keep |
|
650 |
int newlen = 0; |
|
651 |
Object[] temp = new Object[len]; |
|
652 |
for (int i = 0; i < len; ++i) { |
|
653 |
Object element = elements[i]; |
|
654 |
if (!c.contains(element)) |
|
655 |
temp[newlen++] = element; |
|
656 |
} |
|
657 |
if (newlen != len) { |
|
658 |
setArray(Arrays.copyOf(temp, newlen)); |
|
659 |
return true; |
|
660 |
} |
|
661 |
} |
|
662 |
return false; |
|
663 |
} finally { |
|
664 |
lock.unlock(); |
|
665 |
} |
|
666 |
} |
|
667 |
||
668 |
/** |
|
669 |
* Retains only the elements in this list that are contained in the |
|
670 |
* specified collection. In other words, removes from this list all of |
|
671 |
* its elements that are not contained in the specified collection. |
|
672 |
* |
|
673 |
* @param c collection containing elements to be retained in this list |
|
674 |
* @return <tt>true</tt> if this list changed as a result of the call |
|
675 |
* @throws ClassCastException if the class of an element of this list |
|
9504 | 676 |
* is incompatible with the specified collection |
677 |
* (<a href="../Collection.html#optional-restrictions">optional</a>) |
|
2 | 678 |
* @throws NullPointerException if this list contains a null element and the |
9504 | 679 |
* specified collection does not permit null elements |
680 |
* (<a href="../Collection.html#optional-restrictions">optional</a>), |
|
2 | 681 |
* or if the specified collection is null |
682 |
* @see #remove(Object) |
|
683 |
*/ |
|
684 |
public boolean retainAll(Collection<?> c) { |
|
685 |
final ReentrantLock lock = this.lock; |
|
686 |
lock.lock(); |
|
687 |
try { |
|
688 |
Object[] elements = getArray(); |
|
689 |
int len = elements.length; |
|
690 |
if (len != 0) { |
|
691 |
// temp array holds those elements we know we want to keep |
|
692 |
int newlen = 0; |
|
693 |
Object[] temp = new Object[len]; |
|
694 |
for (int i = 0; i < len; ++i) { |
|
695 |
Object element = elements[i]; |
|
696 |
if (c.contains(element)) |
|
697 |
temp[newlen++] = element; |
|
698 |
} |
|
699 |
if (newlen != len) { |
|
700 |
setArray(Arrays.copyOf(temp, newlen)); |
|
701 |
return true; |
|
702 |
} |
|
703 |
} |
|
704 |
return false; |
|
705 |
} finally { |
|
706 |
lock.unlock(); |
|
707 |
} |
|
708 |
} |
|
709 |
||
710 |
/** |
|
711 |
* Appends all of the elements in the specified collection that |
|
712 |
* are not already contained in this list, to the end of |
|
713 |
* this list, in the order that they are returned by the |
|
714 |
* specified collection's iterator. |
|
715 |
* |
|
716 |
* @param c collection containing elements to be added to this list |
|
717 |
* @return the number of elements added |
|
718 |
* @throws NullPointerException if the specified collection is null |
|
719 |
* @see #addIfAbsent(Object) |
|
720 |
*/ |
|
721 |
public int addAllAbsent(Collection<? extends E> c) { |
|
722 |
Object[] cs = c.toArray(); |
|
723 |
if (cs.length == 0) |
|
724 |
return 0; |
|
725 |
Object[] uniq = new Object[cs.length]; |
|
726 |
final ReentrantLock lock = this.lock; |
|
727 |
lock.lock(); |
|
728 |
try { |
|
729 |
Object[] elements = getArray(); |
|
730 |
int len = elements.length; |
|
731 |
int added = 0; |
|
732 |
for (int i = 0; i < cs.length; ++i) { // scan for duplicates |
|
733 |
Object e = cs[i]; |
|
734 |
if (indexOf(e, elements, 0, len) < 0 && |
|
735 |
indexOf(e, uniq, 0, added) < 0) |
|
736 |
uniq[added++] = e; |
|
737 |
} |
|
738 |
if (added > 0) { |
|
739 |
Object[] newElements = Arrays.copyOf(elements, len + added); |
|
740 |
System.arraycopy(uniq, 0, newElements, len, added); |
|
741 |
setArray(newElements); |
|
742 |
} |
|
743 |
return added; |
|
744 |
} finally { |
|
745 |
lock.unlock(); |
|
746 |
} |
|
747 |
} |
|
748 |
||
749 |
/** |
|
750 |
* Removes all of the elements from this list. |
|
751 |
* The list will be empty after this call returns. |
|
752 |
*/ |
|
753 |
public void clear() { |
|
754 |
final ReentrantLock lock = this.lock; |
|
755 |
lock.lock(); |
|
756 |
try { |
|
757 |
setArray(new Object[0]); |
|
758 |
} finally { |
|
759 |
lock.unlock(); |
|
760 |
} |
|
761 |
} |
|
762 |
||
763 |
/** |
|
764 |
* Appends all of the elements in the specified collection to the end |
|
765 |
* of this list, in the order that they are returned by the specified |
|
766 |
* collection's iterator. |
|
767 |
* |
|
768 |
* @param c collection containing elements to be added to this list |
|
769 |
* @return <tt>true</tt> if this list changed as a result of the call |
|
770 |
* @throws NullPointerException if the specified collection is null |
|
771 |
* @see #add(Object) |
|
772 |
*/ |
|
773 |
public boolean addAll(Collection<? extends E> c) { |
|
774 |
Object[] cs = c.toArray(); |
|
775 |
if (cs.length == 0) |
|
776 |
return false; |
|
777 |
final ReentrantLock lock = this.lock; |
|
778 |
lock.lock(); |
|
779 |
try { |
|
780 |
Object[] elements = getArray(); |
|
781 |
int len = elements.length; |
|
782 |
Object[] newElements = Arrays.copyOf(elements, len + cs.length); |
|
783 |
System.arraycopy(cs, 0, newElements, len, cs.length); |
|
784 |
setArray(newElements); |
|
785 |
return true; |
|
786 |
} finally { |
|
787 |
lock.unlock(); |
|
788 |
} |
|
789 |
} |
|
790 |
||
791 |
/** |
|
792 |
* Inserts all of the elements in the specified collection into this |
|
793 |
* list, starting at the specified position. Shifts the element |
|
794 |
* currently at that position (if any) and any subsequent elements to |
|
795 |
* the right (increases their indices). The new elements will appear |
|
796 |
* in this list in the order that they are returned by the |
|
797 |
* specified collection's iterator. |
|
798 |
* |
|
799 |
* @param index index at which to insert the first element |
|
800 |
* from the specified collection |
|
801 |
* @param c collection containing elements to be added to this list |
|
802 |
* @return <tt>true</tt> if this list changed as a result of the call |
|
803 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
804 |
* @throws NullPointerException if the specified collection is null |
|
805 |
* @see #add(int,Object) |
|
806 |
*/ |
|
807 |
public boolean addAll(int index, Collection<? extends E> c) { |
|
808 |
Object[] cs = c.toArray(); |
|
809 |
final ReentrantLock lock = this.lock; |
|
810 |
lock.lock(); |
|
811 |
try { |
|
812 |
Object[] elements = getArray(); |
|
813 |
int len = elements.length; |
|
814 |
if (index > len || index < 0) |
|
815 |
throw new IndexOutOfBoundsException("Index: "+index+ |
|
816 |
", Size: "+len); |
|
817 |
if (cs.length == 0) |
|
818 |
return false; |
|
819 |
int numMoved = len - index; |
|
820 |
Object[] newElements; |
|
821 |
if (numMoved == 0) |
|
822 |
newElements = Arrays.copyOf(elements, len + cs.length); |
|
823 |
else { |
|
824 |
newElements = new Object[len + cs.length]; |
|
825 |
System.arraycopy(elements, 0, newElements, 0, index); |
|
826 |
System.arraycopy(elements, index, |
|
827 |
newElements, index + cs.length, |
|
828 |
numMoved); |
|
829 |
} |
|
830 |
System.arraycopy(cs, 0, newElements, index, cs.length); |
|
831 |
setArray(newElements); |
|
832 |
return true; |
|
833 |
} finally { |
|
834 |
lock.unlock(); |
|
835 |
} |
|
836 |
} |
|
837 |
||
838 |
/** |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
839 |
* Saves the state of the list to a stream (that is, serializes it). |
2 | 840 |
* |
841 |
* @serialData The length of the array backing the list is emitted |
|
842 |
* (int), followed by all of its elements (each an Object) |
|
843 |
* in the proper order. |
|
844 |
* @param s the stream |
|
845 |
*/ |
|
846 |
private void writeObject(java.io.ObjectOutputStream s) |
|
847 |
throws java.io.IOException{ |
|
848 |
||
849 |
s.defaultWriteObject(); |
|
850 |
||
851 |
Object[] elements = getArray(); |
|
852 |
// Write out array length |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
853 |
s.writeInt(elements.length); |
2 | 854 |
|
855 |
// Write out all elements in the proper order. |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
856 |
for (Object element : elements) |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
857 |
s.writeObject(element); |
2 | 858 |
} |
859 |
||
860 |
/** |
|
7976
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
861 |
* Reconstitutes the list from a stream (that is, deserializes it). |
f273c0d04215
7005424: Resync java.util.concurrent classes with Dougs CVS - Jan 2011
dl
parents:
7668
diff
changeset
|
862 |
* |
2 | 863 |
* @param s the stream |
864 |
*/ |
|
865 |
private void readObject(java.io.ObjectInputStream s) |
|
866 |
throws java.io.IOException, ClassNotFoundException { |
|
867 |
||
868 |
s.defaultReadObject(); |
|
869 |
||
870 |
// bind to new lock |
|
871 |
resetLock(); |
|
872 |
||
873 |
// Read in array length and allocate array |
|
874 |
int len = s.readInt(); |
|
875 |
Object[] elements = new Object[len]; |
|
876 |
||
877 |
// Read in all elements in the proper order. |
|
878 |
for (int i = 0; i < len; i++) |
|
879 |
elements[i] = s.readObject(); |
|
880 |
setArray(elements); |
|
881 |
} |
|
882 |
||
883 |
/** |
|
884 |
* Returns a string representation of this list. The string |
|
885 |
* representation consists of the string representations of the list's |
|
886 |
* elements in the order they are returned by its iterator, enclosed in |
|
887 |
* square brackets (<tt>"[]"</tt>). Adjacent elements are separated by |
|
888 |
* the characters <tt>", "</tt> (comma and space). Elements are |
|
889 |
* converted to strings as by {@link String#valueOf(Object)}. |
|
890 |
* |
|
891 |
* @return a string representation of this list |
|
892 |
*/ |
|
893 |
public String toString() { |
|
894 |
return Arrays.toString(getArray()); |
|
895 |
} |
|
896 |
||
897 |
/** |
|
898 |
* Compares the specified object with this list for equality. |
|
899 |
* Returns {@code true} if the specified object is the same object |
|
900 |
* as this object, or if it is also a {@link List} and the sequence |
|
901 |
* of elements returned by an {@linkplain List#iterator() iterator} |
|
902 |
* over the specified list is the same as the sequence returned by |
|
903 |
* an iterator over this list. The two sequences are considered to |
|
904 |
* be the same if they have the same length and corresponding |
|
905 |
* elements at the same position in the sequence are <em>equal</em>. |
|
906 |
* Two elements {@code e1} and {@code e2} are considered |
|
907 |
* <em>equal</em> if {@code (e1==null ? e2==null : e1.equals(e2))}. |
|
908 |
* |
|
909 |
* @param o the object to be compared for equality with this list |
|
910 |
* @return {@code true} if the specified object is equal to this list |
|
911 |
*/ |
|
912 |
public boolean equals(Object o) { |
|
913 |
if (o == this) |
|
914 |
return true; |
|
915 |
if (!(o instanceof List)) |
|
916 |
return false; |
|
917 |
||
918 |
List<?> list = (List<?>)(o); |
|
919 |
Iterator<?> it = list.iterator(); |
|
920 |
Object[] elements = getArray(); |
|
921 |
int len = elements.length; |
|
922 |
for (int i = 0; i < len; ++i) |
|
923 |
if (!it.hasNext() || !eq(elements[i], it.next())) |
|
924 |
return false; |
|
925 |
if (it.hasNext()) |
|
926 |
return false; |
|
927 |
return true; |
|
928 |
} |
|
929 |
||
930 |
/** |
|
931 |
* Returns the hash code value for this list. |
|
932 |
* |
|
933 |
* <p>This implementation uses the definition in {@link List#hashCode}. |
|
934 |
* |
|
935 |
* @return the hash code value for this list |
|
936 |
*/ |
|
937 |
public int hashCode() { |
|
938 |
int hashCode = 1; |
|
939 |
Object[] elements = getArray(); |
|
940 |
int len = elements.length; |
|
941 |
for (int i = 0; i < len; ++i) { |
|
942 |
Object obj = elements[i]; |
|
943 |
hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); |
|
944 |
} |
|
945 |
return hashCode; |
|
946 |
} |
|
947 |
||
948 |
/** |
|
949 |
* Returns an iterator over the elements in this list in proper sequence. |
|
950 |
* |
|
951 |
* <p>The returned iterator provides a snapshot of the state of the list |
|
952 |
* when the iterator was constructed. No synchronization is needed while |
|
953 |
* traversing the iterator. The iterator does <em>NOT</em> support the |
|
954 |
* <tt>remove</tt> method. |
|
955 |
* |
|
956 |
* @return an iterator over the elements in this list in proper sequence |
|
957 |
*/ |
|
958 |
public Iterator<E> iterator() { |
|
959 |
return new COWIterator<E>(getArray(), 0); |
|
960 |
} |
|
961 |
||
962 |
/** |
|
963 |
* {@inheritDoc} |
|
964 |
* |
|
965 |
* <p>The returned iterator provides a snapshot of the state of the list |
|
966 |
* when the iterator was constructed. No synchronization is needed while |
|
967 |
* traversing the iterator. The iterator does <em>NOT</em> support the |
|
968 |
* <tt>remove</tt>, <tt>set</tt> or <tt>add</tt> methods. |
|
969 |
*/ |
|
970 |
public ListIterator<E> listIterator() { |
|
971 |
return new COWIterator<E>(getArray(), 0); |
|
972 |
} |
|
973 |
||
974 |
/** |
|
975 |
* {@inheritDoc} |
|
976 |
* |
|
977 |
* <p>The returned iterator provides a snapshot of the state of the list |
|
978 |
* when the iterator was constructed. No synchronization is needed while |
|
979 |
* traversing the iterator. The iterator does <em>NOT</em> support the |
|
980 |
* <tt>remove</tt>, <tt>set</tt> or <tt>add</tt> methods. |
|
981 |
* |
|
982 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
983 |
*/ |
|
984 |
public ListIterator<E> listIterator(final int index) { |
|
985 |
Object[] elements = getArray(); |
|
986 |
int len = elements.length; |
|
987 |
if (index<0 || index>len) |
|
988 |
throw new IndexOutOfBoundsException("Index: "+index); |
|
989 |
||
990 |
return new COWIterator<E>(elements, index); |
|
991 |
} |
|
992 |
||
993 |
private static class COWIterator<E> implements ListIterator<E> { |
|
7518 | 994 |
/** Snapshot of the array */ |
2 | 995 |
private final Object[] snapshot; |
996 |
/** Index of element to be returned by subsequent call to next. */ |
|
997 |
private int cursor; |
|
998 |
||
999 |
private COWIterator(Object[] elements, int initialCursor) { |
|
1000 |
cursor = initialCursor; |
|
1001 |
snapshot = elements; |
|
1002 |
} |
|
1003 |
||
1004 |
public boolean hasNext() { |
|
1005 |
return cursor < snapshot.length; |
|
1006 |
} |
|
1007 |
||
1008 |
public boolean hasPrevious() { |
|
1009 |
return cursor > 0; |
|
1010 |
} |
|
1011 |
||
1012 |
@SuppressWarnings("unchecked") |
|
1013 |
public E next() { |
|
1014 |
if (! hasNext()) |
|
1015 |
throw new NoSuchElementException(); |
|
1016 |
return (E) snapshot[cursor++]; |
|
1017 |
} |
|
1018 |
||
1019 |
@SuppressWarnings("unchecked") |
|
1020 |
public E previous() { |
|
1021 |
if (! hasPrevious()) |
|
1022 |
throw new NoSuchElementException(); |
|
1023 |
return (E) snapshot[--cursor]; |
|
1024 |
} |
|
1025 |
||
1026 |
public int nextIndex() { |
|
1027 |
return cursor; |
|
1028 |
} |
|
1029 |
||
1030 |
public int previousIndex() { |
|
1031 |
return cursor-1; |
|
1032 |
} |
|
1033 |
||
1034 |
/** |
|
1035 |
* Not supported. Always throws UnsupportedOperationException. |
|
1036 |
* @throws UnsupportedOperationException always; <tt>remove</tt> |
|
1037 |
* is not supported by this iterator. |
|
1038 |
*/ |
|
1039 |
public void remove() { |
|
1040 |
throw new UnsupportedOperationException(); |
|
1041 |
} |
|
1042 |
||
1043 |
/** |
|
1044 |
* Not supported. Always throws UnsupportedOperationException. |
|
1045 |
* @throws UnsupportedOperationException always; <tt>set</tt> |
|
1046 |
* is not supported by this iterator. |
|
1047 |
*/ |
|
1048 |
public void set(E e) { |
|
1049 |
throw new UnsupportedOperationException(); |
|
1050 |
} |
|
1051 |
||
1052 |
/** |
|
1053 |
* Not supported. Always throws UnsupportedOperationException. |
|
1054 |
* @throws UnsupportedOperationException always; <tt>add</tt> |
|
1055 |
* is not supported by this iterator. |
|
1056 |
*/ |
|
1057 |
public void add(E e) { |
|
1058 |
throw new UnsupportedOperationException(); |
|
1059 |
} |
|
1060 |
} |
|
1061 |
||
1062 |
/** |
|
1063 |
* Returns a view of the portion of this list between |
|
1064 |
* <tt>fromIndex</tt>, inclusive, and <tt>toIndex</tt>, exclusive. |
|
1065 |
* The returned list is backed by this list, so changes in the |
|
1066 |
* returned list are reflected in this list. |
|
1067 |
* |
|
1068 |
* <p>The semantics of the list returned by this method become |
|
1069 |
* undefined if the backing list (i.e., this list) is modified in |
|
1070 |
* any way other than via the returned list. |
|
1071 |
* |
|
1072 |
* @param fromIndex low endpoint (inclusive) of the subList |
|
1073 |
* @param toIndex high endpoint (exclusive) of the subList |
|
1074 |
* @return a view of the specified range within this list |
|
1075 |
* @throws IndexOutOfBoundsException {@inheritDoc} |
|
1076 |
*/ |
|
1077 |
public List<E> subList(int fromIndex, int toIndex) { |
|
1078 |
final ReentrantLock lock = this.lock; |
|
1079 |
lock.lock(); |
|
1080 |
try { |
|
1081 |
Object[] elements = getArray(); |
|
1082 |
int len = elements.length; |
|
1083 |
if (fromIndex < 0 || toIndex > len || fromIndex > toIndex) |
|
1084 |
throw new IndexOutOfBoundsException(); |
|
1085 |
return new COWSubList<E>(this, fromIndex, toIndex); |
|
1086 |
} finally { |
|
1087 |
lock.unlock(); |
|
1088 |
} |
|
1089 |
} |
|
1090 |
||
1091 |
/** |
|
1092 |
* Sublist for CopyOnWriteArrayList. |
|
1093 |
* This class extends AbstractList merely for convenience, to |
|
1094 |
* avoid having to define addAll, etc. This doesn't hurt, but |
|
1095 |
* is wasteful. This class does not need or use modCount |
|
1096 |
* mechanics in AbstractList, but does need to check for |
|
1097 |
* concurrent modification using similar mechanics. On each |
|
1098 |
* operation, the array that we expect the backing list to use |
|
1099 |
* is checked and updated. Since we do this for all of the |
|
1100 |
* base operations invoked by those defined in AbstractList, |
|
1101 |
* all is well. While inefficient, this is not worth |
|
1102 |
* improving. The kinds of list operations inherited from |
|
1103 |
* AbstractList are already so slow on COW sublists that |
|
1104 |
* adding a bit more space/time doesn't seem even noticeable. |
|
1105 |
*/ |
|
1106 |
private static class COWSubList<E> |
|
1107 |
extends AbstractList<E> |
|
1108 |
implements RandomAccess |
|
1109 |
{ |
|
1110 |
private final CopyOnWriteArrayList<E> l; |
|
1111 |
private final int offset; |
|
1112 |
private int size; |
|
1113 |
private Object[] expectedArray; |
|
1114 |
||
1115 |
// only call this holding l's lock |
|
1116 |
COWSubList(CopyOnWriteArrayList<E> list, |
|
1117 |
int fromIndex, int toIndex) { |
|
1118 |
l = list; |
|
1119 |
expectedArray = l.getArray(); |
|
1120 |
offset = fromIndex; |
|
1121 |
size = toIndex - fromIndex; |
|
1122 |
} |
|
1123 |
||
1124 |
// only call this holding l's lock |
|
1125 |
private void checkForComodification() { |
|
1126 |
if (l.getArray() != expectedArray) |
|
1127 |
throw new ConcurrentModificationException(); |
|
1128 |
} |
|
1129 |
||
1130 |
// only call this holding l's lock |
|
1131 |
private void rangeCheck(int index) { |
|
1132 |
if (index<0 || index>=size) |
|
1133 |
throw new IndexOutOfBoundsException("Index: "+index+ |
|
1134 |
",Size: "+size); |
|
1135 |
} |
|
1136 |
||
1137 |
public E set(int index, E element) { |
|
1138 |
final ReentrantLock lock = l.lock; |
|
1139 |
lock.lock(); |
|
1140 |
try { |
|
1141 |
rangeCheck(index); |
|
1142 |
checkForComodification(); |
|
1143 |
E x = l.set(index+offset, element); |
|
1144 |
expectedArray = l.getArray(); |
|
1145 |
return x; |
|
1146 |
} finally { |
|
1147 |
lock.unlock(); |
|
1148 |
} |
|
1149 |
} |
|
1150 |
||
1151 |
public E get(int index) { |
|
1152 |
final ReentrantLock lock = l.lock; |
|
1153 |
lock.lock(); |
|
1154 |
try { |
|
1155 |
rangeCheck(index); |
|
1156 |
checkForComodification(); |
|
1157 |
return l.get(index+offset); |
|
1158 |
} finally { |
|
1159 |
lock.unlock(); |
|
1160 |
} |
|
1161 |
} |
|
1162 |
||
1163 |
public int size() { |
|
1164 |
final ReentrantLock lock = l.lock; |
|
1165 |
lock.lock(); |
|
1166 |
try { |
|
1167 |
checkForComodification(); |
|
1168 |
return size; |
|
1169 |
} finally { |
|
1170 |
lock.unlock(); |
|
1171 |
} |
|
1172 |
} |
|
1173 |
||
1174 |
public void add(int index, E element) { |
|
1175 |
final ReentrantLock lock = l.lock; |
|
1176 |
lock.lock(); |
|
1177 |
try { |
|
1178 |
checkForComodification(); |
|
1179 |
if (index<0 || index>size) |
|
1180 |
throw new IndexOutOfBoundsException(); |
|
1181 |
l.add(index+offset, element); |
|
1182 |
expectedArray = l.getArray(); |
|
1183 |
size++; |
|
1184 |
} finally { |
|
1185 |
lock.unlock(); |
|
1186 |
} |
|
1187 |
} |
|
1188 |
||
1189 |
public void clear() { |
|
1190 |
final ReentrantLock lock = l.lock; |
|
1191 |
lock.lock(); |
|
1192 |
try { |
|
1193 |
checkForComodification(); |
|
1194 |
l.removeRange(offset, offset+size); |
|
1195 |
expectedArray = l.getArray(); |
|
1196 |
size = 0; |
|
1197 |
} finally { |
|
1198 |
lock.unlock(); |
|
1199 |
} |
|
1200 |
} |
|
1201 |
||
1202 |
public E remove(int index) { |
|
1203 |
final ReentrantLock lock = l.lock; |
|
1204 |
lock.lock(); |
|
1205 |
try { |
|
1206 |
rangeCheck(index); |
|
1207 |
checkForComodification(); |
|
1208 |
E result = l.remove(index+offset); |
|
1209 |
expectedArray = l.getArray(); |
|
1210 |
size--; |
|
1211 |
return result; |
|
1212 |
} finally { |
|
1213 |
lock.unlock(); |
|
1214 |
} |
|
1215 |
} |
|
1216 |
||
1217 |
public boolean remove(Object o) { |
|
1218 |
int index = indexOf(o); |
|
1219 |
if (index == -1) |
|
1220 |
return false; |
|
1221 |
remove(index); |
|
1222 |
return true; |
|
1223 |
} |
|
1224 |
||
1225 |
public Iterator<E> iterator() { |
|
1226 |
final ReentrantLock lock = l.lock; |
|
1227 |
lock.lock(); |
|
1228 |
try { |
|
1229 |
checkForComodification(); |
|
1230 |
return new COWSubListIterator<E>(l, 0, offset, size); |
|
1231 |
} finally { |
|
1232 |
lock.unlock(); |
|
1233 |
} |
|
1234 |
} |
|
1235 |
||
1236 |
public ListIterator<E> listIterator(final int index) { |
|
1237 |
final ReentrantLock lock = l.lock; |
|
1238 |
lock.lock(); |
|
1239 |
try { |
|
1240 |
checkForComodification(); |
|
1241 |
if (index<0 || index>size) |
|
1242 |
throw new IndexOutOfBoundsException("Index: "+index+ |
|
1243 |
", Size: "+size); |
|
1244 |
return new COWSubListIterator<E>(l, index, offset, size); |
|
1245 |
} finally { |
|
1246 |
lock.unlock(); |
|
1247 |
} |
|
1248 |
} |
|
1249 |
||
1250 |
public List<E> subList(int fromIndex, int toIndex) { |
|
1251 |
final ReentrantLock lock = l.lock; |
|
1252 |
lock.lock(); |
|
1253 |
try { |
|
1254 |
checkForComodification(); |
|
1255 |
if (fromIndex<0 || toIndex>size) |
|
1256 |
throw new IndexOutOfBoundsException(); |
|
1257 |
return new COWSubList<E>(l, fromIndex + offset, |
|
1258 |
toIndex + offset); |
|
1259 |
} finally { |
|
1260 |
lock.unlock(); |
|
1261 |
} |
|
1262 |
} |
|
1263 |
||
1264 |
} |
|
1265 |
||
1266 |
||
1267 |
private static class COWSubListIterator<E> implements ListIterator<E> { |
|
1268 |
private final ListIterator<E> i; |
|
1269 |
private final int index; |
|
1270 |
private final int offset; |
|
1271 |
private final int size; |
|
1272 |
||
1273 |
COWSubListIterator(List<E> l, int index, int offset, |
|
1274 |
int size) { |
|
1275 |
this.index = index; |
|
1276 |
this.offset = offset; |
|
1277 |
this.size = size; |
|
1278 |
i = l.listIterator(index+offset); |
|
1279 |
} |
|
1280 |
||
1281 |
public boolean hasNext() { |
|
1282 |
return nextIndex() < size; |
|
1283 |
} |
|
1284 |
||
1285 |
public E next() { |
|
1286 |
if (hasNext()) |
|
1287 |
return i.next(); |
|
1288 |
else |
|
1289 |
throw new NoSuchElementException(); |
|
1290 |
} |
|
1291 |
||
1292 |
public boolean hasPrevious() { |
|
1293 |
return previousIndex() >= 0; |
|
1294 |
} |
|
1295 |
||
1296 |
public E previous() { |
|
1297 |
if (hasPrevious()) |
|
1298 |
return i.previous(); |
|
1299 |
else |
|
1300 |
throw new NoSuchElementException(); |
|
1301 |
} |
|
1302 |
||
1303 |
public int nextIndex() { |
|
1304 |
return i.nextIndex() - offset; |
|
1305 |
} |
|
1306 |
||
1307 |
public int previousIndex() { |
|
1308 |
return i.previousIndex() - offset; |
|
1309 |
} |
|
1310 |
||
1311 |
public void remove() { |
|
1312 |
throw new UnsupportedOperationException(); |
|
1313 |
} |
|
1314 |
||
1315 |
public void set(E e) { |
|
1316 |
throw new UnsupportedOperationException(); |
|
1317 |
} |
|
1318 |
||
1319 |
public void add(E e) { |
|
1320 |
throw new UnsupportedOperationException(); |
|
1321 |
} |
|
1322 |
} |
|
1323 |
||
1324 |
// Support for resetting lock while deserializing |
|
8544
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1325 |
private void resetLock() { |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1326 |
UNSAFE.putObjectVolatile(this, lockOffset, new ReentrantLock()); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1327 |
} |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1328 |
private static final sun.misc.Unsafe UNSAFE; |
2 | 1329 |
private static final long lockOffset; |
1330 |
static { |
|
1331 |
try { |
|
8544
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1332 |
UNSAFE = sun.misc.Unsafe.getUnsafe(); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1333 |
Class k = CopyOnWriteArrayList.class; |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1334 |
lockOffset = UNSAFE.objectFieldOffset |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1335 |
(k.getDeclaredField("lock")); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1336 |
} catch (Exception e) { |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1337 |
throw new Error(e); |
225896f7b33c
7017493: ConcurrentLinkedDeque: Unexpected initialization order can lead to crash due to use of Unsafe
dl
parents:
7976
diff
changeset
|
1338 |
} |
2 | 1339 |
} |
1340 |
} |