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dl |
1.2 |
/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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tim |
1.7 |
* Expert Group. Adapted and released under explicit permission |
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dl |
1.3 |
* from JDK1.2 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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* This software is the confidential and proprietary information |
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* of Sun Microsystems, Inc. ("Confidential Information"). You |
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* shall not disclose such Confidential Information and shall use |
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* it only in accordance with the terms of the license agreement |
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* you entered into with Sun. |
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dl |
1.2 |
*/ |
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tim |
1.1 |
package java.util.concurrent; |
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import java.util.*; |
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/** |
21 |
dl |
1.4 |
* A variant of {@link java.util.ArrayList} in which all mutative |
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* operations (add, set, and so on) are implemented by making a fresh |
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* copy of the underlying array. <p> |
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tim |
1.1 |
* |
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* This is ordinarily too costly, but it becomes attractive when |
26 |
brian |
1.5 |
* traversal operations vastly outnumber mutations, and, especially |
27 |
tim |
1.1 |
* when you cannot or don't want to synchronize traversals, yet need |
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* to preclude interference among concurrent threads. The iterator |
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* method uses a reference to the state of the array at the point that |
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* the iterator was created. This array never changes during the |
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dl |
1.6 |
* lifetime of the iterator, so interference is impossible and the |
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* iterator is guaranteed not to throw |
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* <tt>ConcurrentModificationException</tt>. The iterator will not |
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* reflect additions, removals, or changes to the List since the |
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* iterator was created. <p> |
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tim |
1.1 |
* |
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* Because of the copy-on-write policy, some one-by-one mutative |
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* operations in the java.util.Arrays and java.util.Collections |
39 |
dl |
1.2 |
* classes are so time/space intensive as to never be worth calling. |
40 |
dl |
1.4 |
* Also, due to their strict read-only nature, element-changing |
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* operations on iterators (remove, set, and add) are not |
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* supported. These are the only methods throwing |
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* UnsupportedOperationException. <p> |
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dl |
1.6 |
* @since 1.5 |
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* @author Doug Lea |
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*/ |
47 |
tim |
1.1 |
public class CopyOnWriteArrayList<E> |
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implements List<E>, RandomAccess, Cloneable, java.io.Serializable { |
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dl |
1.11 |
private static final long serialVersionUID = 8673264195747942595L; |
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tim |
1.1 |
|
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/** |
52 |
dl |
1.6 |
* The held array. Directly accessed only within synchronized |
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tim |
1.1 |
* methods |
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*/ |
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dl |
1.2 |
private volatile transient E[] array_; |
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tim |
1.1 |
|
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/** |
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* Accessor to the array intended to be called from |
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* within unsynchronized read-only methods |
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**/ |
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dl |
1.2 |
private E[] array() { return array_; } |
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tim |
1.1 |
|
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/** |
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tim |
1.9 |
* Constructs an empty list. |
65 |
tim |
1.1 |
*/ |
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public CopyOnWriteArrayList() { |
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tim |
1.7 |
array_ = (E[]) new Object[0]; |
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tim |
1.1 |
} |
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/** |
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* Constructs an 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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dl |
1.6 |
* @param c the collection of initially held elements |
75 |
tim |
1.1 |
*/ |
76 |
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public CopyOnWriteArrayList(Collection<E> c) { |
77 |
tim |
1.7 |
array_ = (E[]) new Object[c.size()]; |
78 |
tim |
1.1 |
Iterator<E> i = c.iterator(); |
79 |
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int size = 0; |
80 |
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while (i.hasNext()) |
81 |
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array_[size++] = i.next(); |
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} |
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/** |
85 |
tim |
1.9 |
* Create a new CopyOnWriteArrayList holding a copy of given array. |
86 |
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* |
87 |
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* @param toCopyIn the array (a copy of this array is used as the |
88 |
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* internal array) |
89 |
tim |
1.1 |
**/ |
90 |
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public CopyOnWriteArrayList(E[] toCopyIn) { |
91 |
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copyIn(toCopyIn, 0, toCopyIn.length); |
92 |
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} |
93 |
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94 |
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/** |
95 |
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* Replace the held array with a copy of the <code>n</code> |
96 |
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* elements of the provided array, starting at position <code>first</code>. |
97 |
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* To copy an entire array, call with arguments (array, 0, array.length). |
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* @param toCopyIn the array. A copy of the indicated elements of |
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* this array is used as the |
100 |
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* internal array. |
101 |
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* @param first The index of first position of the array to |
102 |
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* start copying from. |
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* @param n the number of elements to copy. This will be the new size of |
104 |
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* the list. |
105 |
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**/ |
106 |
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private synchronized void copyIn(E[] toCopyIn, int first, int n) { |
107 |
tim |
1.7 |
array_ = (E[]) new Object[n]; |
108 |
tim |
1.1 |
System.arraycopy(toCopyIn, first, array_, 0, n); |
109 |
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} |
110 |
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111 |
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/** |
112 |
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* Returns the number of components in this list. |
113 |
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* |
114 |
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* @return the number of components in this list. |
115 |
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*/ |
116 |
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public int size() { |
117 |
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return array().length; |
118 |
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} |
119 |
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120 |
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/** |
121 |
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* Tests if this list has no components. |
122 |
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* |
123 |
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* @return <code>true</code> if this list has no components; |
124 |
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* <code>false</code> otherwise. |
125 |
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*/ |
126 |
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public boolean isEmpty() { |
127 |
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return size() == 0; |
128 |
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} |
129 |
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130 |
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/** |
131 |
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* Returns true if this list contains the specified element. |
132 |
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* |
133 |
dl |
1.6 |
* @param elem element whose presence in this List is to be tested. |
134 |
tim |
1.1 |
*/ |
135 |
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public boolean contains(Object elem) { |
136 |
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E[] elementData = array(); |
137 |
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int len = elementData.length; |
138 |
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return indexOf(elem, elementData, len) >= 0; |
139 |
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} |
140 |
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141 |
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/** |
142 |
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* Searches for the first occurence of the given argument, testing |
143 |
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* for equality using the <code>equals</code> method. |
144 |
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* |
145 |
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* @param elem an object. |
146 |
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* @return the index of the first occurrence of the argument in this |
147 |
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* list; returns <code>-1</code> if the object is not found. |
148 |
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* @see Object#equals(Object) |
149 |
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*/ |
150 |
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public int indexOf(Object elem) { |
151 |
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E[] elementData = array(); |
152 |
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int len = elementData.length; |
153 |
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return indexOf(elem, elementData, len); |
154 |
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} |
155 |
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156 |
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157 |
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/** |
158 |
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* static version allows repeated call without needed |
159 |
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* to grab lock for array each time |
160 |
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**/ |
161 |
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private static int indexOf(Object elem, Object[] elementData, int len) { |
162 |
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if (elem == null) { |
163 |
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for (int i = 0; i < len; i++) |
164 |
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if (elementData[i]==null) |
165 |
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return i; |
166 |
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} else { |
167 |
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for (int i = 0; i < len; i++) |
168 |
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if (elem.equals(elementData[i])) |
169 |
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return i; |
170 |
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} |
171 |
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return -1; |
172 |
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} |
173 |
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174 |
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/** |
175 |
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* Searches for the first occurence of the given argument, beginning |
176 |
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* the search at <code>index</code>, and testing for equality using |
177 |
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* the <code>equals</code> method. |
178 |
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* |
179 |
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* @param elem an object. |
180 |
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* @param index the index to start searching from. |
181 |
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* @return the index of the first occurrence of the object argument in |
182 |
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* this List at position <code>index</code> or later in the |
183 |
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* List; returns <code>-1</code> if the object is not found. |
184 |
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* @see Object#equals(Object) |
185 |
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*/ |
186 |
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public int indexOf(E elem, int index) { |
187 |
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E[] elementData = array(); |
188 |
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int elementCount = elementData.length; |
189 |
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190 |
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if (elem == null) { |
191 |
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for (int i = index ; i < elementCount ; i++) |
192 |
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if (elementData[i]==null) |
193 |
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return i; |
194 |
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} else { |
195 |
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for (int i = index ; i < elementCount ; i++) |
196 |
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if (elem.equals(elementData[i])) |
197 |
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return i; |
198 |
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} |
199 |
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return -1; |
200 |
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} |
201 |
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202 |
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/** |
203 |
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* Returns the index of the last occurrence of the specified object in |
204 |
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* this list. |
205 |
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* |
206 |
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* @param elem the desired component. |
207 |
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* @return the index of the last occurrence of the specified object in |
208 |
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* this list; returns -1 if the object is not found. |
209 |
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*/ |
210 |
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public int lastIndexOf(Object elem) { |
211 |
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E[] elementData = array(); |
212 |
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int len = elementData.length; |
213 |
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return lastIndexOf(elem, elementData, len); |
214 |
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} |
215 |
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216 |
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private static int lastIndexOf(Object elem, Object[] elementData, int len) { |
217 |
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if (elem == null) { |
218 |
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for (int i = len-1; i >= 0; i--) |
219 |
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if (elementData[i]==null) |
220 |
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return i; |
221 |
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} else { |
222 |
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for (int i = len-1; i >= 0; i--) |
223 |
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if (elem.equals(elementData[i])) |
224 |
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return i; |
225 |
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} |
226 |
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return -1; |
227 |
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} |
228 |
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229 |
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/** |
230 |
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* Searches backwards for the specified object, starting from the |
231 |
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* specified index, and returns an index to it. |
232 |
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* |
233 |
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* @param elem the desired component. |
234 |
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* @param index the index to start searching from. |
235 |
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* @return the index of the last occurrence of the specified object in this |
236 |
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* List at position less than index in the List; |
237 |
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* -1 if the object is not found. |
238 |
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*/ |
239 |
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public int lastIndexOf(E elem, int index) { |
240 |
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// needed in order to compile on 1.2b3 |
241 |
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E[] elementData = array(); |
242 |
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if (elem == null) { |
243 |
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for (int i = index; i >= 0; i--) |
244 |
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if (elementData[i]==null) |
245 |
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return i; |
246 |
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} else { |
247 |
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for (int i = index; i >= 0; i--) |
248 |
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if (elem.equals(elementData[i])) |
249 |
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return i; |
250 |
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} |
251 |
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return -1; |
252 |
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} |
253 |
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254 |
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/** |
255 |
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* Returns a shallow copy of this list. (The elements themselves |
256 |
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* are not copied.) |
257 |
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* |
258 |
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* @return a clone of this list. |
259 |
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*/ |
260 |
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public Object clone() { |
261 |
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try { |
262 |
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E[] elementData = array(); |
263 |
tim |
1.8 |
CopyOnWriteArrayList<E> v = (CopyOnWriteArrayList<E>)super.clone(); |
264 |
tim |
1.7 |
v.array_ = (E[]) new Object[elementData.length]; |
265 |
tim |
1.1 |
System.arraycopy(elementData, 0, v.array_, 0, elementData.length); |
266 |
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return v; |
267 |
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} catch (CloneNotSupportedException e) { |
268 |
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// this shouldn't happen, since we are Cloneable |
269 |
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throw new InternalError(); |
270 |
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} |
271 |
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} |
272 |
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273 |
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/** |
274 |
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* Returns an array containing all of the elements in this list |
275 |
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* in the correct order. |
276 |
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*/ |
277 |
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public Object[] toArray() { |
278 |
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Object[] elementData = array(); |
279 |
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Object[] result = new Object[elementData.length]; |
280 |
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System.arraycopy(elementData, 0, result, 0, elementData.length); |
281 |
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return result; |
282 |
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} |
283 |
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284 |
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/** |
285 |
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* Returns an array containing all of the elements in this list in the |
286 |
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* correct order. The runtime type of the returned array is that of the |
287 |
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* specified array. If the list fits in the specified array, it is |
288 |
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* returned therein. Otherwise, a new array is allocated with the runtime |
289 |
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* type of the specified array and the size of this list. |
290 |
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* <p> |
291 |
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* If the list fits in the specified array with room to spare |
292 |
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* (i.e., the array has more elements than the list), |
293 |
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* the element in the array immediately following the end of the |
294 |
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* collection is set to null. This is useful in determining the length |
295 |
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* of the list <em>only</em> if the caller knows that the list |
296 |
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* does not contain any null elements. |
297 |
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* |
298 |
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* @param a the array into which the elements of the list are to |
299 |
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* be stored, if it is big enough; otherwise, a new array of the |
300 |
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* same runtime type is allocated for this purpose. |
301 |
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* @return an array containing the elements of the list. |
302 |
dl |
1.6 |
* @throws ArrayStoreException the runtime type of a is not a supertype |
303 |
tim |
1.1 |
* of the runtime type of every element in this list. |
304 |
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*/ |
305 |
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public <T> T[] toArray(T a[]) { |
306 |
|
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E[] elementData = array(); |
307 |
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|
308 |
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if (a.length < elementData.length) |
309 |
|
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a = (T[]) |
310 |
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java.lang.reflect.Array.newInstance(a.getClass().getComponentType(), |
311 |
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elementData.length); |
312 |
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313 |
|
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System.arraycopy(elementData, 0, a, 0, elementData.length); |
314 |
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|
315 |
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if (a.length > elementData.length) |
316 |
|
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a[elementData.length] = null; |
317 |
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318 |
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return a; |
319 |
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} |
320 |
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|
321 |
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// Positional Access Operations |
322 |
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|
323 |
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/** |
324 |
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* Returns the element at the specified position in this list. |
325 |
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* |
326 |
|
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* @param index index of element to return. |
327 |
dl |
1.6 |
* @return the element |
328 |
|
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* @throws IndexOutOfBoundsException index is out of range (index |
329 |
tim |
1.1 |
* < 0 || index >= size()). |
330 |
|
|
*/ |
331 |
|
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public E get(int index) { |
332 |
|
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E[] elementData = array(); |
333 |
|
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rangeCheck(index, elementData.length); |
334 |
|
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return elementData[index]; |
335 |
|
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} |
336 |
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|
337 |
|
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/** |
338 |
|
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* Replaces the element at the specified position in this list with |
339 |
|
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* the specified element. |
340 |
|
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* |
341 |
|
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* @param index index of element to replace. |
342 |
|
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* @param element element to be stored at the specified position. |
343 |
|
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* @return the element previously at the specified position. |
344 |
dl |
1.6 |
* @throws IndexOutOfBoundsException index out of range |
345 |
tim |
1.1 |
* (index < 0 || index >= size()). |
346 |
|
|
*/ |
347 |
|
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public synchronized E set(int index, E element) { |
348 |
|
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int len = array_.length; |
349 |
|
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rangeCheck(index, len); |
350 |
|
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E oldValue = array_[index]; |
351 |
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|
352 |
|
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boolean same = (oldValue == element || |
353 |
|
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(element != null && element.equals(oldValue))); |
354 |
|
|
if (!same) { |
355 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len]; |
356 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, len); |
357 |
|
|
newArray[index] = element; |
358 |
|
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array_ = newArray; |
359 |
|
|
} |
360 |
|
|
return oldValue; |
361 |
|
|
} |
362 |
|
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|
363 |
|
|
/** |
364 |
|
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* Appends the specified element to the end of this list. |
365 |
|
|
* |
366 |
|
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* @param element element to be appended to this list. |
367 |
|
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* @return true (as per the general contract of Collection.add). |
368 |
|
|
*/ |
369 |
|
|
public synchronized boolean add(E element) { |
370 |
|
|
int len = array_.length; |
371 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len+1]; |
372 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, len); |
373 |
|
|
newArray[len] = element; |
374 |
|
|
array_ = newArray; |
375 |
|
|
return true; |
376 |
|
|
} |
377 |
|
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|
378 |
|
|
/** |
379 |
|
|
* Inserts the specified element at the specified position in this |
380 |
|
|
* list. Shifts the element currently at that position (if any) and |
381 |
|
|
* any subsequent elements to the right (adds one to their indices). |
382 |
|
|
* |
383 |
|
|
* @param index index at which the specified element is to be inserted. |
384 |
|
|
* @param element element to be inserted. |
385 |
dl |
1.6 |
* @throws IndexOutOfBoundsException index is out of range |
386 |
tim |
1.1 |
* (index < 0 || index > size()). |
387 |
|
|
*/ |
388 |
|
|
public synchronized void add(int index, E element) { |
389 |
|
|
int len = array_.length; |
390 |
|
|
if (index > len || index < 0) |
391 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+", Size: "+len); |
392 |
|
|
|
393 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len+1]; |
394 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, index); |
395 |
|
|
newArray[index] = element; |
396 |
|
|
System.arraycopy(array_, index, newArray, index+1, len - index); |
397 |
|
|
array_ = newArray; |
398 |
|
|
} |
399 |
|
|
|
400 |
|
|
/** |
401 |
|
|
* Removes the element at the specified position in this list. |
402 |
|
|
* Shifts any subsequent elements to the left (subtracts one from their |
403 |
|
|
* indices). Returns the element that was removed from the list. |
404 |
|
|
* |
405 |
dl |
1.6 |
* @throws IndexOutOfBoundsException index out of range (index |
406 |
tim |
1.1 |
* < 0 || index >= size()). |
407 |
|
|
* @param index the index of the element to removed. |
408 |
|
|
*/ |
409 |
|
|
public synchronized E remove(int index) { |
410 |
|
|
int len = array_.length; |
411 |
|
|
rangeCheck(index, len); |
412 |
|
|
E oldValue = array_[index]; |
413 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len-1]; |
414 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, index); |
415 |
|
|
int numMoved = len - index - 1; |
416 |
|
|
if (numMoved > 0) |
417 |
|
|
System.arraycopy(array_, index+1, newArray, index, numMoved); |
418 |
|
|
array_ = newArray; |
419 |
|
|
return oldValue; |
420 |
|
|
} |
421 |
|
|
|
422 |
|
|
/** |
423 |
|
|
* Removes a single instance of the specified element from this Collection, |
424 |
|
|
* if it is present (optional operation). More formally, removes an |
425 |
|
|
* element <code>e</code> such that <code>(o==null ? e==null : |
426 |
|
|
* o.equals(e))</code>, if the Collection contains one or more such |
427 |
|
|
* elements. Returns true if the Collection contained the specified |
428 |
|
|
* element (or equivalently, if the Collection changed as a result of the |
429 |
|
|
* call). |
430 |
|
|
* |
431 |
|
|
* @param element element to be removed from this Collection, if present. |
432 |
|
|
* @return true if the Collection changed as a result of the call. |
433 |
|
|
*/ |
434 |
|
|
public synchronized boolean remove(Object element) { |
435 |
|
|
int len = array_.length; |
436 |
|
|
if (len == 0) return false; |
437 |
|
|
|
438 |
|
|
// Copy while searching for element to remove |
439 |
|
|
// This wins in the normal case of element being present |
440 |
|
|
|
441 |
|
|
int newlen = len-1; |
442 |
tim |
1.7 |
E[] newArray = (E[]) new Object[newlen]; |
443 |
tim |
1.1 |
|
444 |
|
|
for (int i = 0; i < newlen; ++i) { |
445 |
|
|
if (element == array_[i] || |
446 |
|
|
(element != null && element.equals(array_[i]))) { |
447 |
|
|
// found one; copy remaining and exit |
448 |
|
|
for (int k = i + 1; k < len; ++k) newArray[k-1] = array_[k]; |
449 |
|
|
array_ = newArray; |
450 |
|
|
return true; |
451 |
tim |
1.10 |
} else |
452 |
tim |
1.1 |
newArray[i] = array_[i]; |
453 |
|
|
} |
454 |
|
|
// special handling for last cell |
455 |
|
|
|
456 |
|
|
if (element == array_[newlen] || |
457 |
|
|
(element != null && element.equals(array_[newlen]))) { |
458 |
|
|
array_ = newArray; |
459 |
|
|
return true; |
460 |
tim |
1.10 |
} else |
461 |
tim |
1.1 |
return false; // throw away copy |
462 |
|
|
|
463 |
|
|
} |
464 |
|
|
|
465 |
|
|
|
466 |
|
|
/** |
467 |
|
|
* Removes from this List all of the elements whose index is between |
468 |
|
|
* fromIndex, inclusive and toIndex, exclusive. Shifts any succeeding |
469 |
|
|
* elements to the left (reduces their index). |
470 |
|
|
* This call shortens the List by (toIndex - fromIndex) elements. (If |
471 |
|
|
* toIndex==fromIndex, this operation has no effect.) |
472 |
|
|
* |
473 |
|
|
* @param fromIndex index of first element to be removed. |
474 |
dl |
1.6 |
* @param toIndex index after last element to be removed. |
475 |
|
|
* @throws IndexOutOfBoundsException fromIndex or toIndex out of |
476 |
tim |
1.1 |
* range (fromIndex < 0 || fromIndex >= size() || toIndex |
477 |
|
|
* > size() || toIndex < fromIndex). |
478 |
|
|
*/ |
479 |
|
|
private synchronized void removeRange(int fromIndex, int toIndex) { |
480 |
|
|
int len = array_.length; |
481 |
|
|
|
482 |
|
|
if (fromIndex < 0 || fromIndex >= len || |
483 |
|
|
toIndex > len || toIndex < fromIndex) |
484 |
|
|
throw new IndexOutOfBoundsException(); |
485 |
|
|
|
486 |
|
|
int numMoved = len - toIndex; |
487 |
|
|
int newlen = len - (toIndex-fromIndex); |
488 |
tim |
1.7 |
E[] newArray = (E[]) new Object[newlen]; |
489 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, fromIndex); |
490 |
|
|
System.arraycopy(array_, toIndex, newArray, fromIndex, numMoved); |
491 |
|
|
array_ = newArray; |
492 |
|
|
} |
493 |
|
|
|
494 |
|
|
|
495 |
|
|
/** |
496 |
|
|
* Append the element if not present. |
497 |
|
|
* This operation can be used to obtain Set semantics |
498 |
|
|
* for lists. |
499 |
|
|
* @param element element to be added to this Collection, if absent. |
500 |
|
|
* @return true if added |
501 |
|
|
**/ |
502 |
|
|
public synchronized boolean addIfAbsent(E element) { |
503 |
|
|
// Copy while checking if already present. |
504 |
|
|
// This wins in the most common case where it is not present |
505 |
|
|
int len = array_.length; |
506 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len + 1]; |
507 |
tim |
1.1 |
for (int i = 0; i < len; ++i) { |
508 |
|
|
if (element == array_[i] || |
509 |
|
|
(element != null && element.equals(array_[i]))) |
510 |
|
|
return false; // exit, throwing away copy |
511 |
|
|
else |
512 |
|
|
newArray[i] = array_[i]; |
513 |
|
|
} |
514 |
|
|
newArray[len] = element; |
515 |
|
|
array_ = newArray; |
516 |
|
|
return true; |
517 |
|
|
} |
518 |
|
|
|
519 |
|
|
/** |
520 |
|
|
* Returns true if this Collection contains all of the elements in the |
521 |
|
|
* specified Collection. |
522 |
|
|
* <p> |
523 |
|
|
* This implementation iterates over the specified Collection, checking |
524 |
|
|
* each element returned by the Iterator in turn to see if it's |
525 |
|
|
* contained in this Collection. If all elements are so contained |
526 |
|
|
* true is returned, otherwise false. |
527 |
dl |
1.6 |
* @param c the collection |
528 |
|
|
* @return true if all elements are contained |
529 |
tim |
1.1 |
*/ |
530 |
tim |
1.7 |
public boolean containsAll(Collection<?> c) { |
531 |
tim |
1.1 |
E[] elementData = array(); |
532 |
|
|
int len = elementData.length; |
533 |
tim |
1.7 |
Iterator e = c.iterator(); |
534 |
tim |
1.1 |
while (e.hasNext()) |
535 |
tim |
1.7 |
if (indexOf((E) e.next(), elementData, len) < 0) |
536 |
tim |
1.1 |
return false; |
537 |
|
|
|
538 |
|
|
return true; |
539 |
|
|
} |
540 |
|
|
|
541 |
|
|
|
542 |
|
|
/** |
543 |
|
|
* Removes from this Collection all of its elements that are contained in |
544 |
|
|
* the specified Collection. This is a particularly expensive operation |
545 |
|
|
* in this class because of the need for an internal temporary array. |
546 |
|
|
* <p> |
547 |
|
|
* |
548 |
dl |
1.6 |
* @param c the collection |
549 |
tim |
1.1 |
* @return true if this Collection changed as a result of the call. |
550 |
|
|
*/ |
551 |
tim |
1.7 |
public synchronized boolean removeAll(Collection<?> c) { |
552 |
tim |
1.1 |
E[] elementData = array_; |
553 |
|
|
int len = elementData.length; |
554 |
|
|
if (len == 0) return false; |
555 |
|
|
|
556 |
|
|
// temp array holds those elements we know we want to keep |
557 |
tim |
1.7 |
E[] temp = (E[]) new Object[len]; |
558 |
tim |
1.1 |
int newlen = 0; |
559 |
|
|
for (int i = 0; i < len; ++i) { |
560 |
|
|
E element = elementData[i]; |
561 |
|
|
if (!c.contains(element)) { |
562 |
|
|
temp[newlen++] = element; |
563 |
|
|
} |
564 |
|
|
} |
565 |
|
|
|
566 |
|
|
if (newlen == len) return false; |
567 |
|
|
|
568 |
|
|
// copy temp as new array |
569 |
tim |
1.7 |
E[] newArray = (E[]) new Object[newlen]; |
570 |
tim |
1.1 |
System.arraycopy(temp, 0, newArray, 0, newlen); |
571 |
|
|
array_ = newArray; |
572 |
|
|
return true; |
573 |
|
|
} |
574 |
|
|
|
575 |
|
|
/** |
576 |
|
|
* Retains only the elements in this Collection that are contained in the |
577 |
|
|
* specified Collection (optional operation). In other words, removes from |
578 |
|
|
* this Collection all of its elements that are not contained in the |
579 |
|
|
* specified Collection. |
580 |
dl |
1.6 |
* @param c the collection |
581 |
tim |
1.1 |
* @return true if this Collection changed as a result of the call. |
582 |
|
|
*/ |
583 |
tim |
1.7 |
public synchronized boolean retainAll(Collection<?> c) { |
584 |
tim |
1.1 |
E[] elementData = array_; |
585 |
|
|
int len = elementData.length; |
586 |
|
|
if (len == 0) return false; |
587 |
|
|
|
588 |
tim |
1.7 |
E[] temp = (E[]) new Object[len]; |
589 |
tim |
1.1 |
int newlen = 0; |
590 |
|
|
for (int i = 0; i < len; ++i) { |
591 |
|
|
E element = elementData[i]; |
592 |
|
|
if (c.contains(element)) { |
593 |
|
|
temp[newlen++] = element; |
594 |
|
|
} |
595 |
|
|
} |
596 |
|
|
|
597 |
|
|
if (newlen == len) return false; |
598 |
|
|
|
599 |
tim |
1.7 |
E[] newArray = (E[]) new Object[newlen]; |
600 |
tim |
1.1 |
System.arraycopy(temp, 0, newArray, 0, newlen); |
601 |
|
|
array_ = newArray; |
602 |
|
|
return true; |
603 |
|
|
} |
604 |
|
|
|
605 |
|
|
/** |
606 |
|
|
* Appends all of the elements in the specified Collection that |
607 |
|
|
* are not already contained in this list, to the end of |
608 |
|
|
* this list, in the order that they are returned by the |
609 |
|
|
* specified Collection's Iterator. |
610 |
|
|
* |
611 |
|
|
* @param c elements to be added into this list. |
612 |
|
|
* @return the number of elements added |
613 |
|
|
*/ |
614 |
tim |
1.7 |
public synchronized int addAllAbsent(Collection<? extends E> c) { |
615 |
tim |
1.1 |
int numNew = c.size(); |
616 |
|
|
if (numNew == 0) return 0; |
617 |
|
|
|
618 |
|
|
E[] elementData = array_; |
619 |
|
|
int len = elementData.length; |
620 |
|
|
|
621 |
tim |
1.7 |
E[] temp = (E[]) new Object[numNew]; |
622 |
tim |
1.1 |
int added = 0; |
623 |
tim |
1.7 |
Iterator e = c.iterator(); |
624 |
tim |
1.1 |
while (e.hasNext()) { |
625 |
tim |
1.7 |
E element = (E) e.next(); |
626 |
tim |
1.1 |
if (indexOf(element, elementData, len) < 0) { |
627 |
|
|
if (indexOf(element, temp, added) < 0) { |
628 |
|
|
temp[added++] = element; |
629 |
|
|
} |
630 |
|
|
} |
631 |
|
|
} |
632 |
|
|
|
633 |
|
|
if (added == 0) return 0; |
634 |
|
|
|
635 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len+added]; |
636 |
tim |
1.1 |
System.arraycopy(elementData, 0, newArray, 0, len); |
637 |
|
|
System.arraycopy(temp, 0, newArray, len, added); |
638 |
|
|
array_ = newArray; |
639 |
|
|
return added; |
640 |
|
|
} |
641 |
|
|
|
642 |
|
|
/** |
643 |
|
|
* Removes all of the elements from this list. |
644 |
|
|
* |
645 |
|
|
*/ |
646 |
|
|
public synchronized void clear() { |
647 |
tim |
1.7 |
array_ = (E[]) new Object[0]; |
648 |
tim |
1.1 |
} |
649 |
|
|
|
650 |
|
|
/** |
651 |
|
|
* Appends all of the elements in the specified Collection to the end of |
652 |
|
|
* this list, in the order that they are returned by the |
653 |
|
|
* specified Collection's Iterator. |
654 |
|
|
* |
655 |
|
|
* @param c elements to be inserted into this list. |
656 |
dl |
1.6 |
* @return true if any elements are added |
657 |
tim |
1.1 |
*/ |
658 |
tim |
1.7 |
public synchronized boolean addAll(Collection<? extends E> c) { |
659 |
tim |
1.1 |
int numNew = c.size(); |
660 |
|
|
if (numNew == 0) return false; |
661 |
|
|
|
662 |
|
|
int len = array_.length; |
663 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len+numNew]; |
664 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, len); |
665 |
tim |
1.7 |
Iterator e = c.iterator(); |
666 |
tim |
1.1 |
for (int i=0; i<numNew; i++) |
667 |
tim |
1.7 |
newArray[len++] = (E) e.next(); |
668 |
tim |
1.1 |
array_ = newArray; |
669 |
|
|
|
670 |
|
|
return true; |
671 |
|
|
} |
672 |
|
|
|
673 |
|
|
/** |
674 |
|
|
* Inserts all of the elements in the specified Collection into this |
675 |
|
|
* list, starting at the specified position. Shifts the element |
676 |
|
|
* currently at that position (if any) and any subsequent elements to |
677 |
|
|
* the right (increases their indices). The new elements will appear |
678 |
|
|
* in the list in the order that they are returned by the |
679 |
|
|
* specified Collection's iterator. |
680 |
|
|
* |
681 |
|
|
* @param index index at which to insert first element |
682 |
|
|
* from the specified collection. |
683 |
|
|
* @param c elements to be inserted into this list. |
684 |
dl |
1.6 |
* @throws IndexOutOfBoundsException index out of range (index |
685 |
tim |
1.1 |
* < 0 || index > size()). |
686 |
dl |
1.6 |
* @return true if any elements are added |
687 |
tim |
1.1 |
*/ |
688 |
tim |
1.7 |
public synchronized boolean addAll(int index, Collection<? extends E> c) { |
689 |
tim |
1.1 |
int len = array_.length; |
690 |
|
|
if (index > len || index < 0) |
691 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+", Size: "+len); |
692 |
|
|
|
693 |
|
|
int numNew = c.size(); |
694 |
|
|
if (numNew == 0) return false; |
695 |
|
|
|
696 |
tim |
1.7 |
E[] newArray = (E[]) new Object[len+numNew]; |
697 |
tim |
1.1 |
System.arraycopy(array_, 0, newArray, 0, len); |
698 |
|
|
int numMoved = len - index; |
699 |
|
|
if (numMoved > 0) |
700 |
|
|
System.arraycopy(array_, index, newArray, index + numNew, numMoved); |
701 |
tim |
1.7 |
Iterator e = c.iterator(); |
702 |
tim |
1.1 |
for (int i=0; i<numNew; i++) |
703 |
tim |
1.7 |
newArray[index++] = (E) e.next(); |
704 |
tim |
1.1 |
array_ = newArray; |
705 |
|
|
|
706 |
|
|
return true; |
707 |
|
|
} |
708 |
|
|
|
709 |
|
|
/** |
710 |
|
|
* Check if the given index is in range. If not, throw an appropriate |
711 |
|
|
* runtime exception. |
712 |
|
|
*/ |
713 |
|
|
private void rangeCheck(int index, int length) { |
714 |
|
|
if (index >= length || index < 0) |
715 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+", Size: "+ length); |
716 |
|
|
} |
717 |
|
|
|
718 |
|
|
/** |
719 |
|
|
* Save the state of the list to a stream (i.e., serialize it). |
720 |
|
|
* |
721 |
|
|
* @serialData The length of the array backing the list is emitted |
722 |
|
|
* (int), followed by all of its elements (each an Object) |
723 |
|
|
* in the proper order. |
724 |
dl |
1.6 |
* @param s the stream |
725 |
tim |
1.1 |
*/ |
726 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
727 |
|
|
throws java.io.IOException{ |
728 |
|
|
|
729 |
|
|
// Write out element count, and any hidden stuff |
730 |
|
|
s.defaultWriteObject(); |
731 |
|
|
|
732 |
|
|
E[] elementData = array(); |
733 |
|
|
// Write out array length |
734 |
|
|
s.writeInt(elementData.length); |
735 |
|
|
|
736 |
|
|
// Write out all elements in the proper order. |
737 |
|
|
for (int i=0; i<elementData.length; i++) |
738 |
|
|
s.writeObject(elementData[i]); |
739 |
|
|
} |
740 |
|
|
|
741 |
|
|
/** |
742 |
|
|
* Reconstitute the list from a stream (i.e., deserialize it). |
743 |
dl |
1.6 |
* @param s the stream |
744 |
tim |
1.1 |
*/ |
745 |
|
|
private synchronized void readObject(java.io.ObjectInputStream s) |
746 |
|
|
throws java.io.IOException, ClassNotFoundException { |
747 |
|
|
|
748 |
|
|
// Read in size, and any hidden stuff |
749 |
|
|
s.defaultReadObject(); |
750 |
|
|
|
751 |
|
|
// Read in array length and allocate array |
752 |
|
|
int arrayLength = s.readInt(); |
753 |
tim |
1.7 |
E[] elementData = (E[]) new Object[arrayLength]; |
754 |
tim |
1.1 |
|
755 |
|
|
// Read in all elements in the proper order. |
756 |
|
|
for (int i=0; i<elementData.length; i++) |
757 |
|
|
elementData[i] = (E) s.readObject(); |
758 |
|
|
array_ = elementData; |
759 |
|
|
} |
760 |
|
|
|
761 |
|
|
/** |
762 |
|
|
* Returns a string representation of this Collection, containing |
763 |
|
|
* the String representation of each element. |
764 |
|
|
*/ |
765 |
|
|
public String toString() { |
766 |
|
|
StringBuffer buf = new StringBuffer(); |
767 |
|
|
Iterator e = iterator(); |
768 |
|
|
buf.append("["); |
769 |
|
|
int maxIndex = size() - 1; |
770 |
|
|
for (int i = 0; i <= maxIndex; i++) { |
771 |
|
|
buf.append(String.valueOf(e.next())); |
772 |
|
|
if (i < maxIndex) |
773 |
|
|
buf.append(", "); |
774 |
|
|
} |
775 |
|
|
buf.append("]"); |
776 |
|
|
return buf.toString(); |
777 |
|
|
} |
778 |
|
|
|
779 |
|
|
|
780 |
|
|
/** |
781 |
|
|
* Compares the specified Object with this List for equality. Returns true |
782 |
|
|
* if and only if the specified Object is also a List, both Lists have the |
783 |
|
|
* same size, and all corresponding pairs of elements in the two Lists are |
784 |
|
|
* <em>equal</em>. (Two elements <code>e1</code> and <code>e2</code> are |
785 |
|
|
* <em>equal</em> if <code>(e1==null ? e2==null : e1.equals(e2))</code>.) |
786 |
|
|
* In other words, two Lists are defined to be equal if they contain the |
787 |
|
|
* same elements in the same order. |
788 |
|
|
* <p> |
789 |
|
|
* This implementation first checks if the specified object is this |
790 |
|
|
* List. If so, it returns true; if not, it checks if the specified |
791 |
|
|
* object is a List. If not, it returns false; if so, it iterates over |
792 |
|
|
* both lists, comparing corresponding pairs of elements. If any |
793 |
|
|
* comparison returns false, this method returns false. If either |
794 |
|
|
* Iterator runs out of elements before before the other it returns false |
795 |
|
|
* (as the Lists are of unequal length); otherwise it returns true when |
796 |
|
|
* the iterations complete. |
797 |
|
|
* |
798 |
|
|
* @param o the Object to be compared for equality with this List. |
799 |
|
|
* @return true if the specified Object is equal to this List. |
800 |
|
|
*/ |
801 |
|
|
public boolean equals(Object o) { |
802 |
|
|
if (o == this) |
803 |
|
|
return true; |
804 |
|
|
if (!(o instanceof List)) |
805 |
|
|
return false; |
806 |
|
|
|
807 |
tim |
1.8 |
List<E> l2 = (List<E>)(o); |
808 |
tim |
1.1 |
if (size() != l2.size()) |
809 |
|
|
return false; |
810 |
|
|
|
811 |
|
|
ListIterator<E> e1 = listIterator(); |
812 |
|
|
ListIterator<E> e2 = l2.listIterator(); |
813 |
|
|
while(e1.hasNext()) { |
814 |
|
|
E o1 = e1.next(); |
815 |
|
|
E o2 = e2.next(); |
816 |
|
|
if (!(o1==null ? o2==null : o1.equals(o2))) |
817 |
|
|
return false; |
818 |
|
|
} |
819 |
|
|
return true; |
820 |
|
|
} |
821 |
|
|
|
822 |
|
|
/** |
823 |
|
|
* Returns the hash code value for this List. |
824 |
|
|
* <p> |
825 |
|
|
* This implementation uses exactly the code that is used to define |
826 |
|
|
* the List hash function in the documentation for List.hashCode. |
827 |
|
|
*/ |
828 |
|
|
public int hashCode() { |
829 |
|
|
int hashCode = 1; |
830 |
|
|
Iterator<E> i = iterator(); |
831 |
|
|
while (i.hasNext()) { |
832 |
|
|
E obj = i.next(); |
833 |
|
|
hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); |
834 |
|
|
} |
835 |
|
|
return hashCode; |
836 |
|
|
} |
837 |
|
|
|
838 |
|
|
/** |
839 |
|
|
* Returns an Iterator over the elements contained in this collection. |
840 |
|
|
* The iterator provides a snapshot of the state of the list |
841 |
|
|
* when the iterator was constructed. No synchronization is |
842 |
|
|
* needed while traversing the iterator. The iterator does |
843 |
|
|
* <em>NOT</em> support the <code>remove</code> method. |
844 |
|
|
*/ |
845 |
|
|
public Iterator<E> iterator() { |
846 |
|
|
return new COWIterator<E>(array(), 0); |
847 |
|
|
} |
848 |
|
|
|
849 |
|
|
/** |
850 |
|
|
* Returns an Iterator of the elements in this List (in proper sequence). |
851 |
|
|
* The iterator provides a snapshot of the state of the list |
852 |
|
|
* when the iterator was constructed. No synchronization is |
853 |
|
|
* needed while traversing the iterator. The iterator does |
854 |
|
|
* <em>NOT</em> support the <code>remove</code>, <code>set</code>, |
855 |
|
|
* or <code>add</code> methods. |
856 |
|
|
* |
857 |
|
|
*/ |
858 |
|
|
public ListIterator<E> listIterator() { |
859 |
|
|
return new COWIterator<E>(array(), 0); |
860 |
|
|
} |
861 |
|
|
|
862 |
|
|
/** |
863 |
|
|
* Returns a ListIterator of the elements in this List (in proper |
864 |
|
|
* sequence), starting at the specified position in the List. The |
865 |
|
|
* specified index indicates the first element that would be returned by |
866 |
|
|
* an initial call to nextElement. An initial call to previousElement |
867 |
|
|
* would return the element with the specified index minus one. |
868 |
|
|
* The ListIterator returned by this implementation will throw |
869 |
|
|
* an UnsupportedOperationException in its remove, set and |
870 |
|
|
* add methods. |
871 |
|
|
* |
872 |
|
|
* @param index index of first element to be returned from the |
873 |
|
|
* ListIterator (by a call to getNext). |
874 |
dl |
1.6 |
* @throws IndexOutOfBoundsException index is out of range |
875 |
tim |
1.1 |
* (index < 0 || index > size()). |
876 |
|
|
*/ |
877 |
|
|
public ListIterator<E> listIterator(final int index) { |
878 |
|
|
E[] elementData = array(); |
879 |
|
|
int len = elementData.length; |
880 |
|
|
if (index<0 || index>len) |
881 |
|
|
throw new IndexOutOfBoundsException("Index: "+index); |
882 |
|
|
|
883 |
|
|
return new COWIterator<E>(array(), index); |
884 |
|
|
} |
885 |
|
|
|
886 |
|
|
private static class COWIterator<E> implements ListIterator<E> { |
887 |
|
|
|
888 |
|
|
/** Snapshot of the array **/ |
889 |
|
|
private final E[] array; |
890 |
|
|
|
891 |
|
|
/** |
892 |
|
|
* Index of element to be returned by subsequent call to next. |
893 |
|
|
*/ |
894 |
|
|
private int cursor; |
895 |
|
|
|
896 |
|
|
private COWIterator(E[] elementArray, int initialCursor) { |
897 |
|
|
array = elementArray; |
898 |
|
|
cursor = initialCursor; |
899 |
|
|
} |
900 |
|
|
|
901 |
|
|
public boolean hasNext() { |
902 |
|
|
return cursor < array.length; |
903 |
|
|
} |
904 |
|
|
|
905 |
|
|
public boolean hasPrevious() { |
906 |
|
|
return cursor > 0; |
907 |
|
|
} |
908 |
|
|
|
909 |
|
|
public E next() { |
910 |
|
|
try { |
911 |
|
|
return array[cursor++]; |
912 |
tim |
1.10 |
} catch (IndexOutOfBoundsException ex) { |
913 |
tim |
1.1 |
throw new NoSuchElementException(); |
914 |
|
|
} |
915 |
|
|
} |
916 |
|
|
|
917 |
|
|
public E previous() { |
918 |
|
|
try { |
919 |
|
|
return array[--cursor]; |
920 |
|
|
} catch(IndexOutOfBoundsException e) { |
921 |
|
|
throw new NoSuchElementException(); |
922 |
|
|
} |
923 |
|
|
} |
924 |
|
|
|
925 |
|
|
public int nextIndex() { |
926 |
|
|
return cursor; |
927 |
|
|
} |
928 |
|
|
|
929 |
|
|
public int previousIndex() { |
930 |
|
|
return cursor-1; |
931 |
|
|
} |
932 |
|
|
|
933 |
|
|
/** |
934 |
|
|
* Not supported. Always throws UnsupportedOperationException. |
935 |
dl |
1.6 |
* @throws UnsupportedOperationException remove is not supported |
936 |
tim |
1.1 |
* by this Iterator. |
937 |
|
|
*/ |
938 |
|
|
|
939 |
|
|
public void remove() { |
940 |
|
|
throw new UnsupportedOperationException(); |
941 |
|
|
} |
942 |
|
|
|
943 |
|
|
/** |
944 |
|
|
* Not supported. Always throws UnsupportedOperationException. |
945 |
dl |
1.6 |
* @throws UnsupportedOperationException set is not supported |
946 |
tim |
1.1 |
* by this Iterator. |
947 |
|
|
*/ |
948 |
|
|
public void set(E o) { |
949 |
|
|
throw new UnsupportedOperationException(); |
950 |
|
|
} |
951 |
|
|
|
952 |
|
|
/** |
953 |
|
|
* Not supported. Always throws UnsupportedOperationException. |
954 |
dl |
1.6 |
* @throws UnsupportedOperationException add is not supported |
955 |
tim |
1.1 |
* by this Iterator. |
956 |
|
|
*/ |
957 |
|
|
public void add(E o) { |
958 |
|
|
throw new UnsupportedOperationException(); |
959 |
|
|
} |
960 |
|
|
} |
961 |
|
|
|
962 |
|
|
|
963 |
|
|
/** |
964 |
|
|
* Returns a view of the portion of this List between fromIndex, |
965 |
|
|
* inclusive, and toIndex, exclusive. The returned List is backed by this |
966 |
|
|
* List, so changes in the returned List are reflected in this List, and |
967 |
|
|
* vice-versa. While mutative operations are supported, they are |
968 |
|
|
* probably not very useful for CopyOnWriteArrays. |
969 |
tim |
1.9 |
* <p> |
970 |
tim |
1.1 |
* The semantics of the List returned by this method become undefined if |
971 |
|
|
* the backing list (i.e., this List) is <i>structurally modified</i> in |
972 |
|
|
* any way other than via the returned List. (Structural modifications are |
973 |
|
|
* those that change the size of the List, or otherwise perturb it in such |
974 |
|
|
* a fashion that iterations in progress may yield incorrect results.) |
975 |
|
|
* |
976 |
|
|
* @param fromIndex low endpoint (inclusive) of the subList. |
977 |
dl |
1.6 |
* @param toIndex high endpoint (exclusive) of the subList. |
978 |
tim |
1.1 |
* @return a view of the specified range within this List. |
979 |
dl |
1.6 |
* @throws IndexOutOfBoundsException Illegal endpoint index value |
980 |
tim |
1.1 |
* (fromIndex < 0 || toIndex > size || fromIndex > toIndex). |
981 |
|
|
*/ |
982 |
|
|
public synchronized List<E> subList(int fromIndex, int toIndex) { |
983 |
|
|
// synchronized since sublist ctor depends on it. |
984 |
|
|
int len = array_.length; |
985 |
|
|
if (fromIndex<0 || toIndex>len || fromIndex>toIndex) |
986 |
|
|
throw new IndexOutOfBoundsException(); |
987 |
|
|
return new COWSubList<E>(this, fromIndex, toIndex); |
988 |
|
|
} |
989 |
|
|
|
990 |
|
|
private static class COWSubList<E> extends AbstractList<E> { |
991 |
|
|
|
992 |
|
|
/* |
993 |
dl |
1.2 |
This class extends AbstractList merely for convenience, to |
994 |
|
|
avoid having to define addAll, etc. This doesn't hurt, but |
995 |
|
|
is wasteful. This class does not need or use modCount |
996 |
|
|
mechanics in AbstractList, but does need to check for |
997 |
|
|
concurrent modification using similar mechanics. On each |
998 |
|
|
operation, the array that we expect the backing list to use |
999 |
|
|
is checked and updated. Since we do this for all of the |
1000 |
|
|
base operations invoked by those defined in AbstractList, |
1001 |
|
|
all is well. While inefficient, this is not worth |
1002 |
|
|
improving. The kinds of list operations inherited from |
1003 |
|
|
AbstractList are are already so slow on COW sublists that |
1004 |
|
|
adding a bit more space/time doesn't seem even noticeable. |
1005 |
tim |
1.1 |
*/ |
1006 |
|
|
|
1007 |
|
|
private final CopyOnWriteArrayList<E> l; |
1008 |
|
|
private final int offset; |
1009 |
|
|
private int size; |
1010 |
|
|
private E[] expectedArray; |
1011 |
|
|
|
1012 |
|
|
private COWSubList(CopyOnWriteArrayList<E> list, |
1013 |
|
|
int fromIndex, int toIndex) { |
1014 |
|
|
l = list; |
1015 |
|
|
expectedArray = l.array(); |
1016 |
|
|
offset = fromIndex; |
1017 |
|
|
size = toIndex - fromIndex; |
1018 |
|
|
} |
1019 |
|
|
|
1020 |
|
|
// only call this holding l's lock |
1021 |
|
|
private void checkForComodification() { |
1022 |
|
|
if (l.array_ != expectedArray) |
1023 |
|
|
throw new ConcurrentModificationException(); |
1024 |
|
|
} |
1025 |
|
|
|
1026 |
|
|
// only call this holding l's lock |
1027 |
|
|
private void rangeCheck(int index) { |
1028 |
|
|
if (index<0 || index>=size) |
1029 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+ ",Size: "+size); |
1030 |
|
|
} |
1031 |
|
|
|
1032 |
|
|
|
1033 |
|
|
public E set(int index, E element) { |
1034 |
|
|
synchronized(l) { |
1035 |
|
|
rangeCheck(index); |
1036 |
|
|
checkForComodification(); |
1037 |
|
|
E x = l.set(index+offset, element); |
1038 |
|
|
expectedArray = l.array_; |
1039 |
|
|
return x; |
1040 |
|
|
} |
1041 |
|
|
} |
1042 |
|
|
|
1043 |
|
|
public E get(int index) { |
1044 |
|
|
synchronized(l) { |
1045 |
|
|
rangeCheck(index); |
1046 |
|
|
checkForComodification(); |
1047 |
|
|
return l.get(index+offset); |
1048 |
|
|
} |
1049 |
|
|
} |
1050 |
|
|
|
1051 |
|
|
public int size() { |
1052 |
|
|
synchronized(l) { |
1053 |
|
|
checkForComodification(); |
1054 |
|
|
return size; |
1055 |
|
|
} |
1056 |
|
|
} |
1057 |
|
|
|
1058 |
|
|
public void add(int index, E element) { |
1059 |
|
|
synchronized(l) { |
1060 |
|
|
checkForComodification(); |
1061 |
|
|
if (index<0 || index>size) |
1062 |
|
|
throw new IndexOutOfBoundsException(); |
1063 |
|
|
l.add(index+offset, element); |
1064 |
|
|
expectedArray = l.array_; |
1065 |
|
|
size++; |
1066 |
|
|
} |
1067 |
|
|
} |
1068 |
|
|
|
1069 |
|
|
public E remove(int index) { |
1070 |
|
|
synchronized(l) { |
1071 |
|
|
rangeCheck(index); |
1072 |
|
|
checkForComodification(); |
1073 |
|
|
E result = l.remove(index+offset); |
1074 |
|
|
expectedArray = l.array_; |
1075 |
|
|
size--; |
1076 |
|
|
return result; |
1077 |
|
|
} |
1078 |
|
|
} |
1079 |
|
|
|
1080 |
|
|
public Iterator<E> iterator() { |
1081 |
|
|
synchronized(l) { |
1082 |
|
|
checkForComodification(); |
1083 |
tim |
1.8 |
return new COWSubListIterator<E>(l, 0, offset, size); |
1084 |
tim |
1.1 |
} |
1085 |
|
|
} |
1086 |
|
|
|
1087 |
|
|
public ListIterator<E> listIterator(final int index) { |
1088 |
|
|
synchronized(l) { |
1089 |
|
|
checkForComodification(); |
1090 |
|
|
if (index<0 || index>size) |
1091 |
|
|
throw new IndexOutOfBoundsException("Index: "+index+", Size: "+size); |
1092 |
tim |
1.8 |
return new COWSubListIterator<E>(l, index, offset, size); |
1093 |
tim |
1.1 |
} |
1094 |
|
|
} |
1095 |
|
|
|
1096 |
tim |
1.7 |
public List<E> subList(int fromIndex, int toIndex) { |
1097 |
|
|
synchronized(l) { |
1098 |
|
|
checkForComodification(); |
1099 |
|
|
if (fromIndex<0 || toIndex>size) |
1100 |
|
|
throw new IndexOutOfBoundsException(); |
1101 |
|
|
return new COWSubList<E>(l, fromIndex+offset, toIndex+offset); |
1102 |
tim |
1.1 |
} |
1103 |
tim |
1.7 |
} |
1104 |
tim |
1.1 |
|
1105 |
tim |
1.7 |
} |
1106 |
tim |
1.1 |
|
1107 |
|
|
|
1108 |
tim |
1.7 |
private static class COWSubListIterator<E> implements ListIterator<E> { |
1109 |
|
|
private final ListIterator<E> i; |
1110 |
|
|
private final int index; |
1111 |
|
|
private final int offset; |
1112 |
|
|
private final int size; |
1113 |
|
|
private COWSubListIterator(List<E> l, int index, int offset, int size) { |
1114 |
|
|
this.index = index; |
1115 |
|
|
this.offset = offset; |
1116 |
|
|
this.size = size; |
1117 |
|
|
i = l.listIterator(index+offset); |
1118 |
|
|
} |
1119 |
tim |
1.1 |
|
1120 |
tim |
1.7 |
public boolean hasNext() { |
1121 |
|
|
return nextIndex() < size; |
1122 |
|
|
} |
1123 |
tim |
1.1 |
|
1124 |
tim |
1.7 |
public E next() { |
1125 |
|
|
if (hasNext()) |
1126 |
|
|
return i.next(); |
1127 |
|
|
else |
1128 |
|
|
throw new NoSuchElementException(); |
1129 |
|
|
} |
1130 |
tim |
1.1 |
|
1131 |
tim |
1.7 |
public boolean hasPrevious() { |
1132 |
|
|
return previousIndex() >= 0; |
1133 |
|
|
} |
1134 |
tim |
1.1 |
|
1135 |
tim |
1.7 |
public E previous() { |
1136 |
|
|
if (hasPrevious()) |
1137 |
|
|
return i.previous(); |
1138 |
|
|
else |
1139 |
|
|
throw new NoSuchElementException(); |
1140 |
|
|
} |
1141 |
tim |
1.1 |
|
1142 |
tim |
1.7 |
public int nextIndex() { |
1143 |
|
|
return i.nextIndex() - offset; |
1144 |
|
|
} |
1145 |
tim |
1.1 |
|
1146 |
tim |
1.7 |
public int previousIndex() { |
1147 |
|
|
return i.previousIndex() - offset; |
1148 |
tim |
1.1 |
} |
1149 |
|
|
|
1150 |
tim |
1.7 |
public void remove() { |
1151 |
|
|
throw new UnsupportedOperationException(); |
1152 |
|
|
} |
1153 |
tim |
1.1 |
|
1154 |
tim |
1.7 |
public void set(E o) { |
1155 |
|
|
throw new UnsupportedOperationException(); |
1156 |
tim |
1.1 |
} |
1157 |
|
|
|
1158 |
tim |
1.7 |
public void add(E o) { |
1159 |
|
|
throw new UnsupportedOperationException(); |
1160 |
|
|
} |
1161 |
tim |
1.1 |
} |
1162 |
|
|
|
1163 |
|
|
} |