1 |
|
/* |
2 |
< |
* %W% %E% |
2 |
> |
* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved. |
3 |
> |
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 |
|
* |
5 |
< |
* Copyright 2006 Sun Microsystems, Inc. All rights reserved. |
6 |
< |
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
5 |
> |
* This code is free software; you can redistribute it and/or modify it |
6 |
> |
* under the terms of the GNU General Public License version 2 only, as |
7 |
> |
* published by the Free Software Foundation. Oracle designates this |
8 |
> |
* particular file as subject to the "Classpath" exception as provided |
9 |
> |
* by Oracle in the LICENSE file that accompanied this code. |
10 |
> |
* |
11 |
> |
* This code is distributed in the hope that it will be useful, but WITHOUT |
12 |
> |
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
13 |
> |
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
14 |
> |
* version 2 for more details (a copy is included in the LICENSE file that |
15 |
> |
* accompanied this code). |
16 |
> |
* |
17 |
> |
* You should have received a copy of the GNU General Public License version |
18 |
> |
* 2 along with this work; if not, write to the Free Software Foundation, |
19 |
> |
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
20 |
> |
* |
21 |
> |
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
22 |
> |
* or visit www.oracle.com if you need additional information or have any |
23 |
> |
* questions. |
24 |
|
*/ |
25 |
|
|
26 |
|
package java.util; |
27 |
< |
import java.util.*; // for javadoc (till 6280605 is fixed) |
27 |
> |
|
28 |
> |
import java.util.function.Consumer; |
29 |
> |
import java.util.function.Predicate; |
30 |
> |
import java.util.function.UnaryOperator; |
31 |
|
|
32 |
|
/** |
33 |
< |
* Resizable-array implementation of the <tt>List</tt> interface. Implements |
33 |
> |
* Resizable-array implementation of the {@code List} interface. Implements |
34 |
|
* all optional list operations, and permits all elements, including |
35 |
< |
* <tt>null</tt>. In addition to implementing the <tt>List</tt> interface, |
35 |
> |
* {@code null}. In addition to implementing the {@code List} interface, |
36 |
|
* this class provides methods to manipulate the size of the array that is |
37 |
|
* used internally to store the list. (This class is roughly equivalent to |
38 |
< |
* <tt>Vector</tt>, except that it is unsynchronized.)<p> |
38 |
> |
* {@code Vector}, except that it is unsynchronized.) |
39 |
|
* |
40 |
< |
* The <tt>size</tt>, <tt>isEmpty</tt>, <tt>get</tt>, <tt>set</tt>, |
41 |
< |
* <tt>iterator</tt>, and <tt>listIterator</tt> operations run in constant |
42 |
< |
* time. The <tt>add</tt> operation runs in <i>amortized constant time</i>, |
40 |
> |
* <p>The {@code size}, {@code isEmpty}, {@code get}, {@code set}, |
41 |
> |
* {@code iterator}, and {@code listIterator} operations run in constant |
42 |
> |
* time. The {@code add} operation runs in <i>amortized constant time</i>, |
43 |
|
* that is, adding n elements requires O(n) time. All of the other operations |
44 |
|
* run in linear time (roughly speaking). The constant factor is low compared |
45 |
< |
* to that for the <tt>LinkedList</tt> implementation.<p> |
45 |
> |
* to that for the {@code LinkedList} implementation. |
46 |
|
* |
47 |
< |
* Each <tt>ArrayList</tt> instance has a <i>capacity</i>. The capacity is |
47 |
> |
* <p>Each {@code ArrayList} instance has a <i>capacity</i>. The capacity is |
48 |
|
* the size of the array used to store the elements in the list. It is always |
49 |
|
* at least as large as the list size. As elements are added to an ArrayList, |
50 |
|
* its capacity grows automatically. The details of the growth policy are not |
51 |
|
* specified beyond the fact that adding an element has constant amortized |
52 |
< |
* time cost.<p> |
52 |
> |
* time cost. |
53 |
|
* |
54 |
< |
* An application can increase the capacity of an <tt>ArrayList</tt> instance |
55 |
< |
* before adding a large number of elements using the <tt>ensureCapacity</tt> |
54 |
> |
* <p>An application can increase the capacity of an {@code ArrayList} instance |
55 |
> |
* before adding a large number of elements using the {@code ensureCapacity} |
56 |
|
* operation. This may reduce the amount of incremental reallocation. |
57 |
|
* |
58 |
|
* <p><strong>Note that this implementation is not synchronized.</strong> |
59 |
< |
* If multiple threads access an <tt>ArrayList</tt> instance concurrently, |
59 |
> |
* If multiple threads access an {@code ArrayList} instance concurrently, |
60 |
|
* and at least one of the threads modifies the list structurally, it |
61 |
|
* <i>must</i> be synchronized externally. (A structural modification is |
62 |
|
* any operation that adds or deletes one or more elements, or explicitly |
70 |
|
* unsynchronized access to the list:<pre> |
71 |
|
* List list = Collections.synchronizedList(new ArrayList(...));</pre> |
72 |
|
* |
73 |
< |
* <p>The iterators returned by this class's <tt>iterator</tt> and |
74 |
< |
* <tt>listIterator</tt> methods are <i>fail-fast</i>: if the list is |
75 |
< |
* structurally modified at any time after the iterator is created, in any way |
76 |
< |
* except through the iterator's own <tt>remove</tt> or <tt>add</tt> methods, |
77 |
< |
* the iterator will throw a {@link ConcurrentModificationException}. Thus, in |
78 |
< |
* the face of concurrent modification, the iterator fails quickly and cleanly, |
79 |
< |
* rather than risking arbitrary, non-deterministic behavior at an undetermined |
80 |
< |
* time in the future.<p> |
73 |
> |
* <p id="fail-fast"> |
74 |
> |
* The iterators returned by this class's {@link #iterator() iterator} and |
75 |
> |
* {@link #listIterator(int) listIterator} methods are <em>fail-fast</em>: |
76 |
> |
* if the list is structurally modified at any time after the iterator is |
77 |
> |
* created, in any way except through the iterator's own |
78 |
> |
* {@link ListIterator#remove() remove} or |
79 |
> |
* {@link ListIterator#add(Object) add} methods, the iterator will throw a |
80 |
> |
* {@link ConcurrentModificationException}. Thus, in the face of |
81 |
> |
* concurrent modification, the iterator fails quickly and cleanly, rather |
82 |
> |
* than risking arbitrary, non-deterministic behavior at an undetermined |
83 |
> |
* time in the future. |
84 |
|
* |
85 |
< |
* Note that the fail-fast behavior of an iterator cannot be guaranteed |
85 |
> |
* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed |
86 |
|
* as it is, generally speaking, impossible to make any hard guarantees in the |
87 |
|
* presence of unsynchronized concurrent modification. Fail-fast iterators |
88 |
< |
* throw <tt>ConcurrentModificationException</tt> on a best-effort basis. |
88 |
> |
* throw {@code ConcurrentModificationException} on a best-effort basis. |
89 |
|
* Therefore, it would be wrong to write a program that depended on this |
90 |
< |
* exception for its correctness: <i>the fail-fast behavior of iterators |
91 |
< |
* should be used only to detect bugs.</i><p> |
90 |
> |
* exception for its correctness: <i>the fail-fast behavior of iterators |
91 |
> |
* should be used only to detect bugs.</i> |
92 |
|
* |
93 |
< |
* This class is a member of the |
94 |
< |
* <a href="{@docRoot}/../guide/collections/index.html"> |
93 |
> |
* <p>This class is a member of the |
94 |
> |
* <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
95 |
|
* Java Collections Framework</a>. |
96 |
|
* |
97 |
+ |
* @param <E> the type of elements in this list |
98 |
+ |
* |
99 |
|
* @author Josh Bloch |
100 |
|
* @author Neal Gafter |
101 |
< |
* @version %I%, %G% |
102 |
< |
* @see Collection |
103 |
< |
* @see List |
104 |
< |
* @see LinkedList |
79 |
< |
* @see Vector |
101 |
> |
* @see Collection |
102 |
> |
* @see List |
103 |
> |
* @see LinkedList |
104 |
> |
* @see Vector |
105 |
|
* @since 1.2 |
106 |
|
*/ |
82 |
– |
|
107 |
|
public class ArrayList<E> extends AbstractList<E> |
108 |
|
implements List<E>, RandomAccess, Cloneable, java.io.Serializable |
109 |
|
{ |
110 |
|
private static final long serialVersionUID = 8683452581122892189L; |
111 |
|
|
112 |
|
/** |
113 |
+ |
* Default initial capacity. |
114 |
+ |
*/ |
115 |
+ |
private static final int DEFAULT_CAPACITY = 10; |
116 |
+ |
|
117 |
+ |
/** |
118 |
+ |
* Shared empty array instance used for empty instances. |
119 |
+ |
*/ |
120 |
+ |
private static final Object[] EMPTY_ELEMENTDATA = {}; |
121 |
+ |
|
122 |
+ |
/** |
123 |
+ |
* Shared empty array instance used for default sized empty instances. We |
124 |
+ |
* distinguish this from EMPTY_ELEMENTDATA to know how much to inflate when |
125 |
+ |
* first element is added. |
126 |
+ |
*/ |
127 |
+ |
private static final Object[] DEFAULTCAPACITY_EMPTY_ELEMENTDATA = {}; |
128 |
+ |
|
129 |
+ |
/** |
130 |
|
* The array buffer into which the elements of the ArrayList are stored. |
131 |
< |
* The capacity of the ArrayList is the length of this array buffer. |
131 |
> |
* The capacity of the ArrayList is the length of this array buffer. Any |
132 |
> |
* empty ArrayList with elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA |
133 |
> |
* will be expanded to DEFAULT_CAPACITY when the first element is added. |
134 |
|
*/ |
135 |
< |
private transient Object[] elementData; |
135 |
> |
transient Object[] elementData; // non-private to simplify nested class access |
136 |
|
|
137 |
|
/** |
138 |
|
* The size of the ArrayList (the number of elements it contains). |
144 |
|
/** |
145 |
|
* Constructs an empty list with the specified initial capacity. |
146 |
|
* |
147 |
< |
* @param initialCapacity the initial capacity of the list |
147 |
> |
* @param initialCapacity the initial capacity of the list |
148 |
|
* @throws IllegalArgumentException if the specified initial capacity |
149 |
|
* is negative |
150 |
|
*/ |
151 |
|
public ArrayList(int initialCapacity) { |
152 |
< |
super(); |
153 |
< |
if (initialCapacity < 0) |
152 |
> |
if (initialCapacity > 0) { |
153 |
> |
this.elementData = new Object[initialCapacity]; |
154 |
> |
} else if (initialCapacity == 0) { |
155 |
> |
this.elementData = EMPTY_ELEMENTDATA; |
156 |
> |
} else { |
157 |
|
throw new IllegalArgumentException("Illegal Capacity: "+ |
158 |
|
initialCapacity); |
159 |
< |
this.elementData = new Object[initialCapacity]; |
159 |
> |
} |
160 |
|
} |
161 |
|
|
162 |
|
/** |
163 |
|
* Constructs an empty list with an initial capacity of ten. |
164 |
|
*/ |
165 |
|
public ArrayList() { |
166 |
< |
this(10); |
166 |
> |
this.elementData = DEFAULTCAPACITY_EMPTY_ELEMENTDATA; |
167 |
|
} |
168 |
|
|
169 |
|
/** |
170 |
|
* Constructs a list containing the elements of the specified |
171 |
|
* collection, in the order they are returned by the collection's |
172 |
< |
* iterator. The <tt>ArrayList</tt> instance has an initial capacity of |
127 |
< |
* 110% the size of the specified collection. |
172 |
> |
* iterator. |
173 |
|
* |
174 |
|
* @param c the collection whose elements are to be placed into this list |
175 |
|
* @throws NullPointerException if the specified collection is null |
176 |
|
*/ |
177 |
|
public ArrayList(Collection<? extends E> c) { |
178 |
< |
int size = c.size(); |
179 |
< |
// 10% for growth |
180 |
< |
int cap = ((size/10)+1)*11; |
181 |
< |
if (cap > 0) { |
182 |
< |
Object[] a = new Object[cap]; |
183 |
< |
a[size] = a[size+1] = UNALLOCATED; |
184 |
< |
Object[] b = c.toArray(a); |
185 |
< |
if (b[size] == null && b[size+1] == UNALLOCATED) { |
186 |
< |
b[size+1] = null; |
187 |
< |
elementData = b; |
143 |
< |
this.size = size; |
144 |
< |
return; |
145 |
< |
} |
146 |
< |
} |
147 |
< |
initFromConcurrentlyMutating(c); |
148 |
< |
} |
149 |
< |
|
150 |
< |
private void initFromConcurrentlyMutating(Collection<? extends E> c) { |
151 |
< |
elementData = c.toArray(); |
152 |
< |
size = elementData.length; |
153 |
< |
// c.toArray might (incorrectly) not return Object[] (see 6260652) |
154 |
< |
if (elementData.getClass() != Object[].class) |
155 |
< |
elementData = Arrays.copyOf(elementData, size, Object[].class); |
178 |
> |
elementData = c.toArray(); |
179 |
> |
if ((size = elementData.length) != 0) { |
180 |
> |
// defend against c.toArray (incorrectly) not returning Object[] |
181 |
> |
// (see e.g. https://bugs.openjdk.java.net/browse/JDK-6260652) |
182 |
> |
if (elementData.getClass() != Object[].class) |
183 |
> |
elementData = Arrays.copyOf(elementData, size, Object[].class); |
184 |
> |
} else { |
185 |
> |
// replace with empty array. |
186 |
> |
this.elementData = EMPTY_ELEMENTDATA; |
187 |
> |
} |
188 |
|
} |
189 |
|
|
158 |
– |
private final static Object UNALLOCATED = new Object(); |
159 |
– |
|
190 |
|
/** |
191 |
< |
* Trims the capacity of this <tt>ArrayList</tt> instance to be the |
191 |
> |
* Trims the capacity of this {@code ArrayList} instance to be the |
192 |
|
* list's current size. An application can use this operation to minimize |
193 |
< |
* the storage of an <tt>ArrayList</tt> instance. |
193 |
> |
* the storage of an {@code ArrayList} instance. |
194 |
|
*/ |
195 |
|
public void trimToSize() { |
196 |
< |
modCount++; |
197 |
< |
int oldCapacity = elementData.length; |
198 |
< |
if (size < oldCapacity) { |
199 |
< |
elementData = Arrays.copyOf(elementData, size); |
200 |
< |
} |
196 |
> |
modCount++; |
197 |
> |
if (size < elementData.length) { |
198 |
> |
elementData = (size == 0) |
199 |
> |
? EMPTY_ELEMENTDATA |
200 |
> |
: Arrays.copyOf(elementData, size); |
201 |
> |
} |
202 |
|
} |
203 |
|
|
204 |
|
/** |
205 |
< |
* Increases the capacity of this <tt>ArrayList</tt> instance, if |
205 |
> |
* Increases the capacity of this {@code ArrayList} instance, if |
206 |
|
* necessary, to ensure that it can hold at least the number of elements |
207 |
|
* specified by the minimum capacity argument. |
208 |
|
* |
209 |
|
* @param minCapacity the desired minimum capacity |
210 |
|
*/ |
211 |
|
public void ensureCapacity(int minCapacity) { |
212 |
< |
modCount++; |
213 |
< |
if (minCapacity > elementData.length) |
214 |
< |
growArray(minCapacity); |
212 |
> |
if (minCapacity > elementData.length |
213 |
> |
&& !(elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA |
214 |
> |
&& minCapacity <= DEFAULT_CAPACITY)) { |
215 |
> |
modCount++; |
216 |
> |
grow(minCapacity); |
217 |
> |
} |
218 |
|
} |
219 |
|
|
220 |
|
/** |
221 |
< |
* Increases the capacity of the array. |
221 |
> |
* The maximum size of array to allocate (unless necessary). |
222 |
> |
* Some VMs reserve some header words in an array. |
223 |
> |
* Attempts to allocate larger arrays may result in |
224 |
> |
* OutOfMemoryError: Requested array size exceeds VM limit |
225 |
> |
*/ |
226 |
> |
private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; |
227 |
> |
|
228 |
> |
/** |
229 |
> |
* Increases the capacity to ensure that it can hold at least the |
230 |
> |
* number of elements specified by the minimum capacity argument. |
231 |
|
* |
232 |
|
* @param minCapacity the desired minimum capacity |
233 |
+ |
* @throws OutOfMemoryError if minCapacity is less than zero |
234 |
|
*/ |
235 |
< |
private void growArray(int minCapacity) { |
235 |
> |
private Object[] grow(int minCapacity) { |
236 |
> |
return elementData = Arrays.copyOf(elementData, |
237 |
> |
newCapacity(minCapacity)); |
238 |
> |
} |
239 |
> |
|
240 |
> |
private Object[] grow() { |
241 |
> |
return grow(size + 1); |
242 |
> |
} |
243 |
> |
|
244 |
> |
/** |
245 |
> |
* Returns a capacity at least as large as the given minimum capacity. |
246 |
> |
* Returns the current capacity increased by 50% if that suffices. |
247 |
> |
* Will not return a capacity greater than MAX_ARRAY_SIZE unless |
248 |
> |
* the given minimum capacity is greater than MAX_ARRAY_SIZE. |
249 |
> |
* |
250 |
> |
* @param minCapacity the desired minimum capacity |
251 |
> |
* @throws OutOfMemoryError if minCapacity is less than zero |
252 |
> |
*/ |
253 |
> |
private int newCapacity(int minCapacity) { |
254 |
> |
// overflow-conscious code |
255 |
> |
int oldCapacity = elementData.length; |
256 |
> |
int newCapacity = oldCapacity + (oldCapacity >> 1); |
257 |
> |
if (newCapacity - minCapacity <= 0) { |
258 |
> |
if (elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA) |
259 |
> |
return Math.max(DEFAULT_CAPACITY, minCapacity); |
260 |
> |
if (minCapacity < 0) // overflow |
261 |
> |
throw new OutOfMemoryError(); |
262 |
> |
return minCapacity; |
263 |
> |
} |
264 |
> |
return (newCapacity - MAX_ARRAY_SIZE <= 0) |
265 |
> |
? newCapacity |
266 |
> |
: hugeCapacity(minCapacity); |
267 |
> |
} |
268 |
> |
|
269 |
> |
private static int hugeCapacity(int minCapacity) { |
270 |
|
if (minCapacity < 0) // overflow |
271 |
|
throw new OutOfMemoryError(); |
272 |
< |
int oldCapacity = elementData.length; |
273 |
< |
// Double size if small; else grow by 50% |
274 |
< |
int newCapacity = ((oldCapacity < 64)? |
197 |
< |
((oldCapacity + 1) * 2): |
198 |
< |
((oldCapacity / 2) * 3)); |
199 |
< |
if (newCapacity < 0) // overflow |
200 |
< |
newCapacity = Integer.MAX_VALUE; |
201 |
< |
if (newCapacity < minCapacity) |
202 |
< |
newCapacity = minCapacity; |
203 |
< |
elementData = Arrays.copyOf(elementData, newCapacity); |
272 |
> |
return (minCapacity > MAX_ARRAY_SIZE) |
273 |
> |
? Integer.MAX_VALUE |
274 |
> |
: MAX_ARRAY_SIZE; |
275 |
|
} |
276 |
|
|
277 |
|
/** |
280 |
|
* @return the number of elements in this list |
281 |
|
*/ |
282 |
|
public int size() { |
283 |
< |
return size; |
283 |
> |
return size; |
284 |
|
} |
285 |
|
|
286 |
|
/** |
287 |
< |
* Returns <tt>true</tt> if this list contains no elements. |
287 |
> |
* Returns {@code true} if this list contains no elements. |
288 |
|
* |
289 |
< |
* @return <tt>true</tt> if this list contains no elements |
289 |
> |
* @return {@code true} if this list contains no elements |
290 |
|
*/ |
291 |
|
public boolean isEmpty() { |
292 |
< |
return size == 0; |
292 |
> |
return size == 0; |
293 |
|
} |
294 |
|
|
295 |
|
/** |
296 |
< |
* Returns <tt>true</tt> if this list contains the specified element. |
297 |
< |
* More formally, returns <tt>true</tt> if and only if this list contains |
298 |
< |
* at least one element <tt>e</tt> such that |
299 |
< |
* <tt>(o==null ? e==null : o.equals(e))</tt>. |
296 |
> |
* Returns {@code true} if this list contains the specified element. |
297 |
> |
* More formally, returns {@code true} if and only if this list contains |
298 |
> |
* at least one element {@code e} such that |
299 |
> |
* {@code Objects.equals(o, e)}. |
300 |
|
* |
301 |
|
* @param o element whose presence in this list is to be tested |
302 |
< |
* @return <tt>true</tt> if this list contains the specified element |
302 |
> |
* @return {@code true} if this list contains the specified element |
303 |
|
*/ |
304 |
|
public boolean contains(Object o) { |
305 |
< |
return indexOf(o) >= 0; |
305 |
> |
return indexOf(o) >= 0; |
306 |
|
} |
307 |
|
|
308 |
|
/** |
309 |
|
* Returns the index of the first occurrence of the specified element |
310 |
|
* in this list, or -1 if this list does not contain the element. |
311 |
< |
* More formally, returns the lowest index <tt>i</tt> such that |
312 |
< |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
311 |
> |
* More formally, returns the lowest index {@code i} such that |
312 |
> |
* {@code Objects.equals(o, get(i))}, |
313 |
|
* or -1 if there is no such index. |
314 |
|
*/ |
315 |
|
public int indexOf(Object o) { |
316 |
< |
if (o == null) { |
317 |
< |
for (int i = 0; i < size; i++) |
318 |
< |
if (elementData[i]==null) |
319 |
< |
return i; |
320 |
< |
} else { |
321 |
< |
for (int i = 0; i < size; i++) |
322 |
< |
if (o.equals(elementData[i])) |
323 |
< |
return i; |
324 |
< |
} |
325 |
< |
return -1; |
316 |
> |
if (o == null) { |
317 |
> |
for (int i = 0; i < size; i++) |
318 |
> |
if (elementData[i]==null) |
319 |
> |
return i; |
320 |
> |
} else { |
321 |
> |
for (int i = 0; i < size; i++) |
322 |
> |
if (o.equals(elementData[i])) |
323 |
> |
return i; |
324 |
> |
} |
325 |
> |
return -1; |
326 |
|
} |
327 |
|
|
328 |
|
/** |
329 |
|
* Returns the index of the last occurrence of the specified element |
330 |
|
* in this list, or -1 if this list does not contain the element. |
331 |
< |
* More formally, returns the highest index <tt>i</tt> such that |
332 |
< |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, |
331 |
> |
* More formally, returns the highest index {@code i} such that |
332 |
> |
* {@code Objects.equals(o, get(i))}, |
333 |
|
* or -1 if there is no such index. |
334 |
|
*/ |
335 |
|
public int lastIndexOf(Object o) { |
336 |
< |
if (o == null) { |
337 |
< |
for (int i = size-1; i >= 0; i--) |
338 |
< |
if (elementData[i]==null) |
339 |
< |
return i; |
340 |
< |
} else { |
341 |
< |
for (int i = size-1; i >= 0; i--) |
342 |
< |
if (o.equals(elementData[i])) |
343 |
< |
return i; |
344 |
< |
} |
345 |
< |
return -1; |
336 |
> |
if (o == null) { |
337 |
> |
for (int i = size-1; i >= 0; i--) |
338 |
> |
if (elementData[i]==null) |
339 |
> |
return i; |
340 |
> |
} else { |
341 |
> |
for (int i = size-1; i >= 0; i--) |
342 |
> |
if (o.equals(elementData[i])) |
343 |
> |
return i; |
344 |
> |
} |
345 |
> |
return -1; |
346 |
|
} |
347 |
|
|
348 |
|
/** |
349 |
< |
* Returns a shallow copy of this <tt>ArrayList</tt> instance. (The |
349 |
> |
* Returns a shallow copy of this {@code ArrayList} instance. (The |
350 |
|
* elements themselves are not copied.) |
351 |
|
* |
352 |
< |
* @return a clone of this <tt>ArrayList</tt> instance |
352 |
> |
* @return a clone of this {@code ArrayList} instance |
353 |
|
*/ |
354 |
|
public Object clone() { |
355 |
< |
try { |
356 |
< |
ArrayList<E> v = (ArrayList<E>) super.clone(); |
357 |
< |
v.elementData = Arrays.copyOf(elementData, size); |
358 |
< |
v.modCount = 0; |
359 |
< |
return v; |
360 |
< |
} catch (CloneNotSupportedException e) { |
361 |
< |
// this shouldn't happen, since we are Cloneable |
362 |
< |
throw new InternalError(); |
363 |
< |
} |
355 |
> |
try { |
356 |
> |
ArrayList<?> v = (ArrayList<?>) super.clone(); |
357 |
> |
v.elementData = Arrays.copyOf(elementData, size); |
358 |
> |
v.modCount = 0; |
359 |
> |
return v; |
360 |
> |
} catch (CloneNotSupportedException e) { |
361 |
> |
// this shouldn't happen, since we are Cloneable |
362 |
> |
throw new InternalError(e); |
363 |
> |
} |
364 |
|
} |
365 |
|
|
366 |
|
/** |
392 |
|
* <p>If the list fits in the specified array with room to spare |
393 |
|
* (i.e., the array has more elements than the list), the element in |
394 |
|
* the array immediately following the end of the collection is set to |
395 |
< |
* <tt>null</tt>. (This is useful in determining the length of the |
395 |
> |
* {@code null}. (This is useful in determining the length of the |
396 |
|
* list <i>only</i> if the caller knows that the list does not contain |
397 |
|
* any null elements.) |
398 |
|
* |
405 |
|
* this list |
406 |
|
* @throws NullPointerException if the specified array is null |
407 |
|
*/ |
408 |
+ |
@SuppressWarnings("unchecked") |
409 |
|
public <T> T[] toArray(T[] a) { |
410 |
|
if (a.length < size) |
411 |
|
// Make a new array of a's runtime type, but my contents: |
412 |
|
return (T[]) Arrays.copyOf(elementData, size, a.getClass()); |
413 |
< |
System.arraycopy(elementData, 0, a, 0, size); |
413 |
> |
System.arraycopy(elementData, 0, a, 0, size); |
414 |
|
if (a.length > size) |
415 |
|
a[size] = null; |
416 |
|
return a; |
418 |
|
|
419 |
|
// Positional Access Operations |
420 |
|
|
421 |
< |
/** |
422 |
< |
* Returns error message string for IndexOutOfBoundsExceptions |
423 |
< |
*/ |
352 |
< |
private String ioobe(int index) { |
353 |
< |
return "Index: " + index + ", Size: " + size; |
421 |
> |
@SuppressWarnings("unchecked") |
422 |
> |
E elementData(int index) { |
423 |
> |
return (E) elementData[index]; |
424 |
|
} |
425 |
|
|
426 |
|
/** |
431 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
432 |
|
*/ |
433 |
|
public E get(int index) { |
434 |
< |
if (index >= size) |
435 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
366 |
< |
return (E)elementData[index]; |
434 |
> |
Objects.checkIndex(index, size); |
435 |
> |
return elementData(index); |
436 |
|
} |
437 |
|
|
438 |
|
/** |
445 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
446 |
|
*/ |
447 |
|
public E set(int index, E element) { |
448 |
< |
if (index >= size) |
449 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
448 |
> |
Objects.checkIndex(index, size); |
449 |
> |
E oldValue = elementData(index); |
450 |
> |
elementData[index] = element; |
451 |
> |
return oldValue; |
452 |
> |
} |
453 |
|
|
454 |
< |
E oldValue = (E) elementData[index]; |
455 |
< |
elementData[index] = element; |
456 |
< |
return oldValue; |
454 |
> |
/** |
455 |
> |
* This helper method split out from add(E) to keep method |
456 |
> |
* bytecode size under 35 (the -XX:MaxInlineSize default value), |
457 |
> |
* which helps when add(E) is called in a C1-compiled loop. |
458 |
> |
*/ |
459 |
> |
private void add(E e, Object[] elementData, int s) { |
460 |
> |
if (s == elementData.length) |
461 |
> |
elementData = grow(); |
462 |
> |
elementData[s] = e; |
463 |
> |
size = s + 1; |
464 |
|
} |
465 |
|
|
466 |
|
/** |
467 |
|
* Appends the specified element to the end of this list. |
468 |
|
* |
469 |
|
* @param e element to be appended to this list |
470 |
< |
* @return <tt>true</tt> (as specified by {@link Collection#add}) |
470 |
> |
* @return {@code true} (as specified by {@link Collection#add}) |
471 |
|
*/ |
472 |
|
public boolean add(E e) { |
473 |
|
modCount++; |
474 |
< |
int s = size; |
475 |
< |
if (s >= elementData.length) |
397 |
< |
growArray(s + 1); |
398 |
< |
elementData[s] = e; |
399 |
< |
size = s + 1; |
400 |
< |
return true; |
474 |
> |
add(e, elementData, size); |
475 |
> |
return true; |
476 |
|
} |
477 |
|
|
478 |
|
/** |
485 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
486 |
|
*/ |
487 |
|
public void add(int index, E element) { |
488 |
< |
int s = size; |
489 |
< |
if (index > s || index < 0) |
490 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
491 |
< |
modCount++; |
492 |
< |
if (s >= elementData.length) |
493 |
< |
growArray(s + 1); |
494 |
< |
System.arraycopy(elementData, index, |
495 |
< |
elementData, index + 1, s - index); |
496 |
< |
elementData[index] = element; |
488 |
> |
rangeCheckForAdd(index); |
489 |
> |
modCount++; |
490 |
> |
final int s; |
491 |
> |
Object[] elementData; |
492 |
> |
if ((s = size) == (elementData = this.elementData).length) |
493 |
> |
elementData = grow(); |
494 |
> |
System.arraycopy(elementData, index, |
495 |
> |
elementData, index + 1, |
496 |
> |
s - index); |
497 |
> |
elementData[index] = element; |
498 |
|
size = s + 1; |
499 |
|
} |
500 |
|
|
508 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
509 |
|
*/ |
510 |
|
public E remove(int index) { |
511 |
< |
int s = size - 1; |
512 |
< |
if (index > s) |
513 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
514 |
< |
modCount++; |
515 |
< |
E oldValue = (E)elementData[index]; |
516 |
< |
int numMoved = s - index; |
517 |
< |
if (numMoved > 0) |
518 |
< |
System.arraycopy(elementData, index + 1, |
519 |
< |
elementData, index, numMoved); |
520 |
< |
elementData[s] = null; |
521 |
< |
size = s; |
522 |
< |
return oldValue; |
511 |
> |
Objects.checkIndex(index, size); |
512 |
> |
|
513 |
> |
modCount++; |
514 |
> |
E oldValue = elementData(index); |
515 |
> |
|
516 |
> |
int numMoved = size - index - 1; |
517 |
> |
if (numMoved > 0) |
518 |
> |
System.arraycopy(elementData, index+1, elementData, index, |
519 |
> |
numMoved); |
520 |
> |
elementData[--size] = null; // clear to let GC do its work |
521 |
> |
|
522 |
> |
return oldValue; |
523 |
|
} |
524 |
|
|
525 |
|
/** |
526 |
|
* Removes the first occurrence of the specified element from this list, |
527 |
|
* if it is present. If the list does not contain the element, it is |
528 |
|
* unchanged. More formally, removes the element with the lowest index |
529 |
< |
* <tt>i</tt> such that |
530 |
< |
* <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt> |
531 |
< |
* (if such an element exists). Returns <tt>true</tt> if this list |
529 |
> |
* {@code i} such that |
530 |
> |
* {@code Objects.equals(o, get(i))} |
531 |
> |
* (if such an element exists). Returns {@code true} if this list |
532 |
|
* contained the specified element (or equivalently, if this list |
533 |
|
* changed as a result of the call). |
534 |
|
* |
535 |
|
* @param o element to be removed from this list, if present |
536 |
< |
* @return <tt>true</tt> if this list contained the specified element |
536 |
> |
* @return {@code true} if this list contained the specified element |
537 |
|
*/ |
538 |
|
public boolean remove(Object o) { |
539 |
< |
if (o == null) { |
539 |
> |
if (o == null) { |
540 |
|
for (int index = 0; index < size; index++) |
541 |
< |
if (elementData[index] == null) { |
542 |
< |
fastRemove(index); |
543 |
< |
return true; |
544 |
< |
} |
545 |
< |
} else { |
546 |
< |
for (int index = 0; index < size; index++) |
547 |
< |
if (o.equals(elementData[index])) { |
548 |
< |
fastRemove(index); |
549 |
< |
return true; |
550 |
< |
} |
541 |
> |
if (elementData[index] == null) { |
542 |
> |
fastRemove(index); |
543 |
> |
return true; |
544 |
> |
} |
545 |
> |
} else { |
546 |
> |
for (int index = 0; index < size; index++) |
547 |
> |
if (o.equals(elementData[index])) { |
548 |
> |
fastRemove(index); |
549 |
> |
return true; |
550 |
> |
} |
551 |
|
} |
552 |
< |
return false; |
552 |
> |
return false; |
553 |
|
} |
554 |
|
|
555 |
|
/* |
562 |
|
if (numMoved > 0) |
563 |
|
System.arraycopy(elementData, index+1, elementData, index, |
564 |
|
numMoved); |
565 |
< |
elementData[--size] = null; // Let gc do its work |
565 |
> |
elementData[--size] = null; // clear to let GC do its work |
566 |
|
} |
567 |
|
|
568 |
|
/** |
570 |
|
* be empty after this call returns. |
571 |
|
*/ |
572 |
|
public void clear() { |
573 |
< |
modCount++; |
573 |
> |
modCount++; |
574 |
|
|
575 |
< |
// Let gc do its work |
576 |
< |
for (int i = 0; i < size; i++) |
577 |
< |
elementData[i] = null; |
575 |
> |
// clear to let GC do its work |
576 |
> |
for (int i = 0; i < size; i++) |
577 |
> |
elementData[i] = null; |
578 |
|
|
579 |
< |
size = 0; |
579 |
> |
size = 0; |
580 |
|
} |
581 |
|
|
582 |
|
/** |
589 |
|
* list is nonempty.) |
590 |
|
* |
591 |
|
* @param c collection containing elements to be added to this list |
592 |
< |
* @return <tt>true</tt> if this list changed as a result of the call |
592 |
> |
* @return {@code true} if this list changed as a result of the call |
593 |
|
* @throws NullPointerException if the specified collection is null |
594 |
|
*/ |
595 |
|
public boolean addAll(Collection<? extends E> c) { |
596 |
< |
Object[] a = c.toArray(); |
596 |
> |
Object[] a = c.toArray(); |
597 |
> |
modCount++; |
598 |
|
int numNew = a.length; |
599 |
< |
ensureCapacity(size + numNew); // Increments modCount |
600 |
< |
System.arraycopy(a, 0, elementData, size, numNew); |
601 |
< |
size += numNew; |
602 |
< |
return numNew != 0; |
599 |
> |
if (numNew == 0) |
600 |
> |
return false; |
601 |
> |
Object[] elementData; |
602 |
> |
final int s; |
603 |
> |
if (numNew > (elementData = this.elementData).length - (s = size)) |
604 |
> |
elementData = grow(s + numNew); |
605 |
> |
System.arraycopy(a, 0, elementData, s, numNew); |
606 |
> |
size = s + numNew; |
607 |
> |
return true; |
608 |
|
} |
609 |
|
|
610 |
|
/** |
618 |
|
* @param index index at which to insert the first element from the |
619 |
|
* specified collection |
620 |
|
* @param c collection containing elements to be added to this list |
621 |
< |
* @return <tt>true</tt> if this list changed as a result of the call |
621 |
> |
* @return {@code true} if this list changed as a result of the call |
622 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
623 |
|
* @throws NullPointerException if the specified collection is null |
624 |
|
*/ |
625 |
|
public boolean addAll(int index, Collection<? extends E> c) { |
626 |
< |
if (index > size || index < 0) |
545 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
626 |
> |
rangeCheckForAdd(index); |
627 |
|
|
628 |
< |
Object[] a = c.toArray(); |
629 |
< |
int numNew = a.length; |
630 |
< |
ensureCapacity(size + numNew); // Increments modCount |
631 |
< |
|
632 |
< |
int numMoved = size - index; |
633 |
< |
if (numMoved > 0) |
634 |
< |
System.arraycopy(elementData, index, elementData, index + numNew, |
635 |
< |
numMoved); |
628 |
> |
Object[] a = c.toArray(); |
629 |
> |
modCount++; |
630 |
> |
int numNew = a.length; |
631 |
> |
if (numNew == 0) |
632 |
> |
return false; |
633 |
> |
Object[] elementData; |
634 |
> |
final int s; |
635 |
> |
if (numNew > (elementData = this.elementData).length - (s = size)) |
636 |
> |
elementData = grow(s + numNew); |
637 |
|
|
638 |
+ |
int numMoved = s - index; |
639 |
+ |
if (numMoved > 0) |
640 |
+ |
System.arraycopy(elementData, index, |
641 |
+ |
elementData, index + numNew, |
642 |
+ |
numMoved); |
643 |
|
System.arraycopy(a, 0, elementData, index, numNew); |
644 |
< |
size += numNew; |
645 |
< |
return numNew != 0; |
644 |
> |
size = s + numNew; |
645 |
> |
return true; |
646 |
|
} |
647 |
|
|
648 |
|
/** |
649 |
|
* Removes from this list all of the elements whose index is between |
650 |
< |
* <tt>fromIndex</tt>, inclusive, and <tt>toIndex</tt>, exclusive. |
650 |
> |
* {@code fromIndex}, inclusive, and {@code toIndex}, exclusive. |
651 |
|
* Shifts any succeeding elements to the left (reduces their index). |
652 |
< |
* This call shortens the list by <tt>(toIndex - fromIndex)</tt> elements. |
653 |
< |
* (If <tt>toIndex==fromIndex</tt>, this operation has no effect.) |
652 |
> |
* This call shortens the list by {@code (toIndex - fromIndex)} elements. |
653 |
> |
* (If {@code toIndex==fromIndex}, this operation has no effect.) |
654 |
|
* |
655 |
< |
* @param fromIndex index of first element to be removed |
656 |
< |
* @param toIndex index after last element to be removed |
657 |
< |
* @throws IndexOutOfBoundsException if fromIndex or toIndex out of |
658 |
< |
* range (fromIndex < 0 || fromIndex >= size() || toIndex |
659 |
< |
* > size() || toIndex < fromIndex) |
655 |
> |
* @throws IndexOutOfBoundsException if {@code fromIndex} or |
656 |
> |
* {@code toIndex} is out of range |
657 |
> |
* ({@code fromIndex < 0 || |
658 |
> |
* toIndex > size() || |
659 |
> |
* toIndex < fromIndex}) |
660 |
|
*/ |
661 |
|
protected void removeRange(int fromIndex, int toIndex) { |
662 |
< |
modCount++; |
663 |
< |
int numMoved = size - toIndex; |
662 |
> |
if (fromIndex > toIndex) { |
663 |
> |
throw new IndexOutOfBoundsException( |
664 |
> |
outOfBoundsMsg(fromIndex, toIndex)); |
665 |
> |
} |
666 |
> |
modCount++; |
667 |
> |
int numMoved = size - toIndex; |
668 |
|
System.arraycopy(elementData, toIndex, elementData, fromIndex, |
669 |
|
numMoved); |
670 |
|
|
671 |
< |
// Let gc do its work |
672 |
< |
int newSize = size - (toIndex-fromIndex); |
673 |
< |
while (size != newSize) |
674 |
< |
elementData[--size] = null; |
671 |
> |
// clear to let GC do its work |
672 |
> |
int newSize = size - (toIndex-fromIndex); |
673 |
> |
for (int i = newSize; i < size; i++) { |
674 |
> |
elementData[i] = null; |
675 |
> |
} |
676 |
> |
size = newSize; |
677 |
> |
} |
678 |
> |
|
679 |
> |
/** |
680 |
> |
* A version of rangeCheck used by add and addAll. |
681 |
> |
*/ |
682 |
> |
private void rangeCheckForAdd(int index) { |
683 |
> |
if (index > size || index < 0) |
684 |
> |
throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); |
685 |
> |
} |
686 |
> |
|
687 |
> |
/** |
688 |
> |
* Constructs an IndexOutOfBoundsException detail message. |
689 |
> |
* Of the many possible refactorings of the error handling code, |
690 |
> |
* this "outlining" performs best with both server and client VMs. |
691 |
> |
*/ |
692 |
> |
private String outOfBoundsMsg(int index) { |
693 |
> |
return "Index: "+index+", Size: "+size; |
694 |
> |
} |
695 |
> |
|
696 |
> |
/** |
697 |
> |
* A version used in checking (fromIndex > toIndex) condition |
698 |
> |
*/ |
699 |
> |
private static String outOfBoundsMsg(int fromIndex, int toIndex) { |
700 |
> |
return "From Index: " + fromIndex + " > To Index: " + toIndex; |
701 |
> |
} |
702 |
> |
|
703 |
> |
/** |
704 |
> |
* Removes from this list all of its elements that are contained in the |
705 |
> |
* specified collection. |
706 |
> |
* |
707 |
> |
* @param c collection containing elements to be removed from this list |
708 |
> |
* @return {@code true} if this list changed as a result of the call |
709 |
> |
* @throws ClassCastException if the class of an element of this list |
710 |
> |
* is incompatible with the specified collection |
711 |
> |
* (<a href="Collection.html#optional-restrictions">optional</a>) |
712 |
> |
* @throws NullPointerException if this list contains a null element and the |
713 |
> |
* specified collection does not permit null elements |
714 |
> |
* (<a href="Collection.html#optional-restrictions">optional</a>), |
715 |
> |
* or if the specified collection is null |
716 |
> |
* @see Collection#contains(Object) |
717 |
> |
*/ |
718 |
> |
public boolean removeAll(Collection<?> c) { |
719 |
> |
Objects.requireNonNull(c); |
720 |
> |
return batchRemove(c, false); |
721 |
> |
} |
722 |
> |
|
723 |
> |
/** |
724 |
> |
* Retains only the elements in this list that are contained in the |
725 |
> |
* specified collection. In other words, removes from this list all |
726 |
> |
* of its elements that are not contained in the specified collection. |
727 |
> |
* |
728 |
> |
* @param c collection containing elements to be retained in this list |
729 |
> |
* @return {@code true} if this list changed as a result of the call |
730 |
> |
* @throws ClassCastException if the class of an element of this list |
731 |
> |
* is incompatible with the specified collection |
732 |
> |
* (<a href="Collection.html#optional-restrictions">optional</a>) |
733 |
> |
* @throws NullPointerException if this list contains a null element and the |
734 |
> |
* specified collection does not permit null elements |
735 |
> |
* (<a href="Collection.html#optional-restrictions">optional</a>), |
736 |
> |
* or if the specified collection is null |
737 |
> |
* @see Collection#contains(Object) |
738 |
> |
*/ |
739 |
> |
public boolean retainAll(Collection<?> c) { |
740 |
> |
Objects.requireNonNull(c); |
741 |
> |
return batchRemove(c, true); |
742 |
> |
} |
743 |
> |
|
744 |
> |
private boolean batchRemove(Collection<?> c, boolean complement) { |
745 |
> |
final Object[] elementData = this.elementData; |
746 |
> |
int r = 0, w = 0; |
747 |
> |
boolean modified = false; |
748 |
> |
try { |
749 |
> |
for (; r < size; r++) |
750 |
> |
if (c.contains(elementData[r]) == complement) |
751 |
> |
elementData[w++] = elementData[r]; |
752 |
> |
} finally { |
753 |
> |
// Preserve behavioral compatibility with AbstractCollection, |
754 |
> |
// even if c.contains() throws. |
755 |
> |
if (r != size) { |
756 |
> |
System.arraycopy(elementData, r, |
757 |
> |
elementData, w, |
758 |
> |
size - r); |
759 |
> |
w += size - r; |
760 |
> |
} |
761 |
> |
if (w != size) { |
762 |
> |
// clear to let GC do its work |
763 |
> |
for (int i = w; i < size; i++) |
764 |
> |
elementData[i] = null; |
765 |
> |
modCount += size - w; |
766 |
> |
size = w; |
767 |
> |
modified = true; |
768 |
> |
} |
769 |
> |
} |
770 |
> |
return modified; |
771 |
|
} |
772 |
|
|
773 |
|
/** |
774 |
< |
* Save the state of the <tt>ArrayList</tt> instance to a stream (that |
774 |
> |
* Save the state of the {@code ArrayList} instance to a stream (that |
775 |
|
* is, serialize it). |
776 |
|
* |
777 |
< |
* @serialData The length of the array backing the <tt>ArrayList</tt> |
777 |
> |
* @serialData The length of the array backing the {@code ArrayList} |
778 |
|
* instance is emitted (int), followed by all of its elements |
779 |
< |
* (each an <tt>Object</tt>) in the proper order. |
779 |
> |
* (each an {@code Object}) in the proper order. |
780 |
|
*/ |
781 |
|
private void writeObject(java.io.ObjectOutputStream s) |
782 |
|
throws java.io.IOException{ |
783 |
< |
// Write out element count, and any hidden stuff |
784 |
< |
int expectedModCount = modCount; |
785 |
< |
s.defaultWriteObject(); |
783 |
> |
// Write out element count, and any hidden stuff |
784 |
> |
int expectedModCount = modCount; |
785 |
> |
s.defaultWriteObject(); |
786 |
|
|
787 |
< |
// Write out array length |
788 |
< |
s.writeInt(elementData.length); |
787 |
> |
// Write out size as capacity for behavioural compatibility with clone() |
788 |
> |
s.writeInt(size); |
789 |
|
|
790 |
< |
// Write out all elements in the proper order. |
791 |
< |
for (int i=0; i<size; i++) |
790 |
> |
// Write out all elements in the proper order. |
791 |
> |
for (int i=0; i<size; i++) { |
792 |
|
s.writeObject(elementData[i]); |
793 |
+ |
} |
794 |
|
|
795 |
< |
if (expectedModCount != modCount) { |
795 |
> |
if (modCount != expectedModCount) { |
796 |
|
throw new ConcurrentModificationException(); |
797 |
|
} |
610 |
– |
|
798 |
|
} |
799 |
|
|
800 |
|
/** |
801 |
< |
* Reconstitute the <tt>ArrayList</tt> instance from a stream (that is, |
801 |
> |
* Reconstitute the {@code ArrayList} instance from a stream (that is, |
802 |
|
* deserialize it). |
803 |
|
*/ |
804 |
|
private void readObject(java.io.ObjectInputStream s) |
805 |
|
throws java.io.IOException, ClassNotFoundException { |
619 |
– |
// Read in size, and any hidden stuff |
620 |
– |
s.defaultReadObject(); |
806 |
|
|
807 |
< |
// Read in array length and allocate array |
808 |
< |
int arrayLength = s.readInt(); |
624 |
< |
Object[] a = elementData = new Object[arrayLength]; |
807 |
> |
// Read in size, and any hidden stuff |
808 |
> |
s.defaultReadObject(); |
809 |
|
|
810 |
< |
// Read in all elements in the proper order. |
811 |
< |
for (int i=0; i<size; i++) |
812 |
< |
a[i] = s.readObject(); |
813 |
< |
} |
810 |
> |
// Read in capacity |
811 |
> |
s.readInt(); // ignored |
812 |
> |
|
813 |
> |
if (size > 0) { |
814 |
> |
// like clone(), allocate array based upon size not capacity |
815 |
> |
Object[] elements = new Object[size]; |
816 |
> |
|
817 |
> |
// Read in all elements in the proper order. |
818 |
> |
for (int i = 0; i < size; i++) { |
819 |
> |
elements[i] = s.readObject(); |
820 |
> |
} |
821 |
|
|
822 |
+ |
elementData = elements; |
823 |
+ |
} else if (size == 0) { |
824 |
+ |
elementData = EMPTY_ELEMENTDATA; |
825 |
+ |
} else { |
826 |
+ |
throw new java.io.InvalidObjectException("Invalid size: " + size); |
827 |
+ |
} |
828 |
+ |
} |
829 |
|
|
830 |
|
/** |
831 |
< |
* Returns a list-iterator of the elements in this list (in proper |
831 |
> |
* Returns a list iterator over the elements in this list (in proper |
832 |
|
* sequence), starting at the specified position in the list. |
833 |
< |
* Obeys the general contract of <tt>List.listIterator(int)</tt>.<p> |
833 |
> |
* The specified index indicates the first element that would be |
834 |
> |
* returned by an initial call to {@link ListIterator#next next}. |
835 |
> |
* An initial call to {@link ListIterator#previous previous} would |
836 |
> |
* return the element with the specified index minus one. |
837 |
> |
* |
838 |
> |
* <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>. |
839 |
|
* |
637 |
– |
* The list-iterator is <i>fail-fast</i>: if the list is structurally |
638 |
– |
* modified at any time after the Iterator is created, in any way except |
639 |
– |
* through the list-iterator's own <tt>remove</tt> or <tt>add</tt> |
640 |
– |
* methods, the list-iterator will throw a |
641 |
– |
* <tt>ConcurrentModificationException</tt>. Thus, in the face of |
642 |
– |
* concurrent modification, the iterator fails quickly and cleanly, rather |
643 |
– |
* than risking arbitrary, non-deterministic behavior at an undetermined |
644 |
– |
* time in the future. |
645 |
– |
* |
646 |
– |
* @param index index of the first element to be returned from the |
647 |
– |
* list-iterator (by a call to <tt>next</tt>) |
648 |
– |
* @return a ListIterator of the elements in this list (in proper |
649 |
– |
* sequence), starting at the specified position in the list |
840 |
|
* @throws IndexOutOfBoundsException {@inheritDoc} |
651 |
– |
* @see List#listIterator(int) |
841 |
|
*/ |
842 |
|
public ListIterator<E> listIterator(int index) { |
843 |
< |
if (index < 0 || index > size) |
844 |
< |
throw new IndexOutOfBoundsException(ioobe(index)); |
656 |
< |
return new ArrayListIterator(index); |
843 |
> |
rangeCheckForAdd(index); |
844 |
> |
return new ListItr(index); |
845 |
|
} |
846 |
|
|
847 |
|
/** |
848 |
< |
* {@inheritDoc} |
848 |
> |
* Returns a list iterator over the elements in this list (in proper |
849 |
> |
* sequence). |
850 |
> |
* |
851 |
> |
* <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>. |
852 |
> |
* |
853 |
> |
* @see #listIterator(int) |
854 |
|
*/ |
855 |
|
public ListIterator<E> listIterator() { |
856 |
< |
return new ArrayListIterator(0); |
856 |
> |
return new ListItr(0); |
857 |
|
} |
858 |
|
|
859 |
|
/** |
860 |
|
* Returns an iterator over the elements in this list in proper sequence. |
861 |
|
* |
862 |
+ |
* <p>The returned iterator is <a href="#fail-fast"><i>fail-fast</i></a>. |
863 |
+ |
* |
864 |
|
* @return an iterator over the elements in this list in proper sequence |
865 |
|
*/ |
866 |
|
public Iterator<E> iterator() { |
867 |
< |
return new ArrayListIterator(0); |
867 |
> |
return new Itr(); |
868 |
|
} |
869 |
|
|
870 |
|
/** |
871 |
< |
* A streamlined version of AbstractList.ListItr |
871 |
> |
* An optimized version of AbstractList.Itr |
872 |
|
*/ |
873 |
< |
final class ArrayListIterator implements ListIterator<E> { |
874 |
< |
int cursor; // index of next element to return; |
875 |
< |
int lastRet; // index of last element, or -1 if no such |
876 |
< |
int expectedModCount; // to check for CME |
873 |
> |
private class Itr implements Iterator<E> { |
874 |
> |
int cursor; // index of next element to return |
875 |
> |
int lastRet = -1; // index of last element returned; -1 if no such |
876 |
> |
int expectedModCount = modCount; |
877 |
|
|
878 |
< |
ArrayListIterator(int index) { |
879 |
< |
cursor = index; |
685 |
< |
lastRet = -1; |
686 |
< |
expectedModCount = modCount; |
687 |
< |
} |
878 |
> |
// prevent creating a synthetic constructor |
879 |
> |
Itr() {} |
880 |
|
|
881 |
< |
public boolean hasNext() { |
881 |
> |
public boolean hasNext() { |
882 |
|
return cursor != size; |
883 |
< |
} |
692 |
< |
|
693 |
< |
public boolean hasPrevious() { |
694 |
< |
return cursor != 0; |
695 |
< |
} |
883 |
> |
} |
884 |
|
|
885 |
< |
public int nextIndex() { |
886 |
< |
return cursor; |
887 |
< |
} |
885 |
> |
@SuppressWarnings("unchecked") |
886 |
> |
public E next() { |
887 |
> |
checkForComodification(); |
888 |
> |
int i = cursor; |
889 |
> |
if (i >= size) |
890 |
> |
throw new NoSuchElementException(); |
891 |
> |
Object[] elementData = ArrayList.this.elementData; |
892 |
> |
if (i >= elementData.length) |
893 |
> |
throw new ConcurrentModificationException(); |
894 |
> |
cursor = i + 1; |
895 |
> |
return (E) elementData[lastRet = i]; |
896 |
> |
} |
897 |
|
|
898 |
< |
public int previousIndex() { |
899 |
< |
return cursor - 1; |
900 |
< |
} |
898 |
> |
public void remove() { |
899 |
> |
if (lastRet < 0) |
900 |
> |
throw new IllegalStateException(); |
901 |
> |
checkForComodification(); |
902 |
|
|
705 |
– |
public E next() { |
903 |
|
try { |
904 |
< |
int i = cursor; |
905 |
< |
E next = get(i); |
906 |
< |
lastRet = i; |
907 |
< |
cursor = i + 1; |
711 |
< |
return next; |
904 |
> |
ArrayList.this.remove(lastRet); |
905 |
> |
cursor = lastRet; |
906 |
> |
lastRet = -1; |
907 |
> |
expectedModCount = modCount; |
908 |
|
} catch (IndexOutOfBoundsException ex) { |
909 |
< |
throw new NoSuchElementException(); |
714 |
< |
} finally { |
715 |
< |
if (expectedModCount != modCount) |
716 |
< |
throw new ConcurrentModificationException(); |
909 |
> |
throw new ConcurrentModificationException(); |
910 |
|
} |
911 |
< |
} |
911 |
> |
} |
912 |
|
|
913 |
< |
public E previous() { |
914 |
< |
try { |
915 |
< |
int i = cursor - 1; |
916 |
< |
E prev = get(i); |
917 |
< |
lastRet = i; |
918 |
< |
cursor = i; |
919 |
< |
return prev; |
920 |
< |
} catch (IndexOutOfBoundsException ex) { |
728 |
< |
throw new NoSuchElementException(); |
729 |
< |
} finally { |
730 |
< |
if (expectedModCount != modCount) |
731 |
< |
throw new ConcurrentModificationException(); |
913 |
> |
@Override |
914 |
> |
@SuppressWarnings("unchecked") |
915 |
> |
public void forEachRemaining(Consumer<? super E> consumer) { |
916 |
> |
Objects.requireNonNull(consumer); |
917 |
> |
final int size = ArrayList.this.size; |
918 |
> |
int i = cursor; |
919 |
> |
if (i >= size) { |
920 |
> |
return; |
921 |
|
} |
922 |
+ |
final Object[] elementData = ArrayList.this.elementData; |
923 |
+ |
if (i >= elementData.length) { |
924 |
+ |
throw new ConcurrentModificationException(); |
925 |
+ |
} |
926 |
+ |
while (i != size && modCount == expectedModCount) { |
927 |
+ |
consumer.accept((E) elementData[i++]); |
928 |
+ |
} |
929 |
+ |
// update once at end of iteration to reduce heap write traffic |
930 |
+ |
cursor = i; |
931 |
+ |
lastRet = i - 1; |
932 |
+ |
checkForComodification(); |
933 |
|
} |
934 |
|
|
935 |
< |
public void remove() { |
936 |
< |
if (lastRet < 0) |
737 |
< |
throw new IllegalStateException(); |
738 |
< |
if (expectedModCount != modCount) |
935 |
> |
final void checkForComodification() { |
936 |
> |
if (modCount != expectedModCount) |
937 |
|
throw new ConcurrentModificationException(); |
938 |
< |
ArrayList.this.remove(lastRet); |
939 |
< |
if (lastRet < cursor) |
940 |
< |
cursor--; |
941 |
< |
lastRet = -1; |
942 |
< |
expectedModCount = modCount; |
943 |
< |
} |
944 |
< |
|
945 |
< |
public void set(E e) { |
946 |
< |
if (lastRet < 0) |
947 |
< |
throw new IllegalStateException(); |
948 |
< |
if (expectedModCount != modCount) |
938 |
> |
} |
939 |
> |
} |
940 |
> |
|
941 |
> |
/** |
942 |
> |
* An optimized version of AbstractList.ListItr |
943 |
> |
*/ |
944 |
> |
private class ListItr extends Itr implements ListIterator<E> { |
945 |
> |
ListItr(int index) { |
946 |
> |
super(); |
947 |
> |
cursor = index; |
948 |
> |
} |
949 |
> |
|
950 |
> |
public boolean hasPrevious() { |
951 |
> |
return cursor != 0; |
952 |
> |
} |
953 |
> |
|
954 |
> |
public int nextIndex() { |
955 |
> |
return cursor; |
956 |
> |
} |
957 |
> |
|
958 |
> |
public int previousIndex() { |
959 |
> |
return cursor - 1; |
960 |
> |
} |
961 |
> |
|
962 |
> |
@SuppressWarnings("unchecked") |
963 |
> |
public E previous() { |
964 |
> |
checkForComodification(); |
965 |
> |
int i = cursor - 1; |
966 |
> |
if (i < 0) |
967 |
> |
throw new NoSuchElementException(); |
968 |
> |
Object[] elementData = ArrayList.this.elementData; |
969 |
> |
if (i >= elementData.length) |
970 |
|
throw new ConcurrentModificationException(); |
971 |
< |
ArrayList.this.set(lastRet, e); |
972 |
< |
expectedModCount = modCount; |
973 |
< |
} |
971 |
> |
cursor = i; |
972 |
> |
return (E) elementData[lastRet = i]; |
973 |
> |
} |
974 |
> |
|
975 |
> |
public void set(E e) { |
976 |
> |
if (lastRet < 0) |
977 |
> |
throw new IllegalStateException(); |
978 |
> |
checkForComodification(); |
979 |
|
|
980 |
< |
public void add(E e) { |
981 |
< |
if (expectedModCount != modCount) |
980 |
> |
try { |
981 |
> |
ArrayList.this.set(lastRet, e); |
982 |
> |
} catch (IndexOutOfBoundsException ex) { |
983 |
|
throw new ConcurrentModificationException(); |
984 |
< |
try { |
985 |
< |
ArrayList.this.add(cursor++, e); |
984 |
> |
} |
985 |
> |
} |
986 |
> |
|
987 |
> |
public void add(E e) { |
988 |
> |
checkForComodification(); |
989 |
> |
|
990 |
> |
try { |
991 |
> |
int i = cursor; |
992 |
> |
ArrayList.this.add(i, e); |
993 |
> |
cursor = i + 1; |
994 |
|
lastRet = -1; |
995 |
|
expectedModCount = modCount; |
996 |
< |
} catch (IndexOutOfBoundsException ex) { |
997 |
< |
throw new ConcurrentModificationException(); |
998 |
< |
} |
999 |
< |
} |
996 |
> |
} catch (IndexOutOfBoundsException ex) { |
997 |
> |
throw new ConcurrentModificationException(); |
998 |
> |
} |
999 |
> |
} |
1000 |
> |
} |
1001 |
> |
|
1002 |
> |
/** |
1003 |
> |
* Returns a view of the portion of this list between the specified |
1004 |
> |
* {@code fromIndex}, inclusive, and {@code toIndex}, exclusive. (If |
1005 |
> |
* {@code fromIndex} and {@code toIndex} are equal, the returned list is |
1006 |
> |
* empty.) The returned list is backed by this list, so non-structural |
1007 |
> |
* changes in the returned list are reflected in this list, and vice-versa. |
1008 |
> |
* The returned list supports all of the optional list operations. |
1009 |
> |
* |
1010 |
> |
* <p>This method eliminates the need for explicit range operations (of |
1011 |
> |
* the sort that commonly exist for arrays). Any operation that expects |
1012 |
> |
* a list can be used as a range operation by passing a subList view |
1013 |
> |
* instead of a whole list. For example, the following idiom |
1014 |
> |
* removes a range of elements from a list: |
1015 |
> |
* <pre> |
1016 |
> |
* list.subList(from, to).clear(); |
1017 |
> |
* </pre> |
1018 |
> |
* Similar idioms may be constructed for {@link #indexOf(Object)} and |
1019 |
> |
* {@link #lastIndexOf(Object)}, and all of the algorithms in the |
1020 |
> |
* {@link Collections} class can be applied to a subList. |
1021 |
> |
* |
1022 |
> |
* <p>The semantics of the list returned by this method become undefined if |
1023 |
> |
* the backing list (i.e., this list) is <i>structurally modified</i> in |
1024 |
> |
* any way other than via the returned list. (Structural modifications are |
1025 |
> |
* those that change the size of this list, or otherwise perturb it in such |
1026 |
> |
* a fashion that iterations in progress may yield incorrect results.) |
1027 |
> |
* |
1028 |
> |
* @throws IndexOutOfBoundsException {@inheritDoc} |
1029 |
> |
* @throws IllegalArgumentException {@inheritDoc} |
1030 |
> |
*/ |
1031 |
> |
public List<E> subList(int fromIndex, int toIndex) { |
1032 |
> |
subListRangeCheck(fromIndex, toIndex, size); |
1033 |
> |
return new SubList<>(this, fromIndex, toIndex); |
1034 |
> |
} |
1035 |
> |
|
1036 |
> |
private static class SubList<E> extends AbstractList<E> implements RandomAccess { |
1037 |
> |
private final ArrayList<E> root; |
1038 |
> |
private final SubList<E> parent; |
1039 |
> |
private final int offset; |
1040 |
> |
private int size; |
1041 |
> |
|
1042 |
> |
/** |
1043 |
> |
* Constructs a sublist of an arbitrary ArrayList. |
1044 |
> |
*/ |
1045 |
> |
public SubList(ArrayList<E> root, int fromIndex, int toIndex) { |
1046 |
> |
this.root = root; |
1047 |
> |
this.parent = null; |
1048 |
> |
this.offset = fromIndex; |
1049 |
> |
this.size = toIndex - fromIndex; |
1050 |
> |
this.modCount = root.modCount; |
1051 |
> |
} |
1052 |
> |
|
1053 |
> |
/** |
1054 |
> |
* Constructs a sublist of another SubList. |
1055 |
> |
*/ |
1056 |
> |
private SubList(SubList<E> parent, int fromIndex, int toIndex) { |
1057 |
> |
this.root = parent.root; |
1058 |
> |
this.parent = parent; |
1059 |
> |
this.offset = parent.offset + fromIndex; |
1060 |
> |
this.size = toIndex - fromIndex; |
1061 |
> |
this.modCount = root.modCount; |
1062 |
> |
} |
1063 |
> |
|
1064 |
> |
public E set(int index, E element) { |
1065 |
> |
Objects.checkIndex(index, size); |
1066 |
> |
checkForComodification(); |
1067 |
> |
E oldValue = root.elementData(offset + index); |
1068 |
> |
root.elementData[offset + index] = element; |
1069 |
> |
return oldValue; |
1070 |
> |
} |
1071 |
> |
|
1072 |
> |
public E get(int index) { |
1073 |
> |
Objects.checkIndex(index, size); |
1074 |
> |
checkForComodification(); |
1075 |
> |
return root.elementData(offset + index); |
1076 |
> |
} |
1077 |
> |
|
1078 |
> |
public int size() { |
1079 |
> |
checkForComodification(); |
1080 |
> |
return size; |
1081 |
> |
} |
1082 |
> |
|
1083 |
> |
public void add(int index, E element) { |
1084 |
> |
rangeCheckForAdd(index); |
1085 |
> |
checkForComodification(); |
1086 |
> |
root.add(offset + index, element); |
1087 |
> |
updateSizeAndModCount(1); |
1088 |
> |
} |
1089 |
> |
|
1090 |
> |
public E remove(int index) { |
1091 |
> |
Objects.checkIndex(index, size); |
1092 |
> |
checkForComodification(); |
1093 |
> |
E result = root.remove(offset + index); |
1094 |
> |
updateSizeAndModCount(-1); |
1095 |
> |
return result; |
1096 |
> |
} |
1097 |
> |
|
1098 |
> |
protected void removeRange(int fromIndex, int toIndex) { |
1099 |
> |
checkForComodification(); |
1100 |
> |
root.removeRange(offset + fromIndex, offset + toIndex); |
1101 |
> |
updateSizeAndModCount(fromIndex - toIndex); |
1102 |
> |
} |
1103 |
> |
|
1104 |
> |
public boolean addAll(Collection<? extends E> c) { |
1105 |
> |
return addAll(this.size, c); |
1106 |
> |
} |
1107 |
> |
|
1108 |
> |
public boolean addAll(int index, Collection<? extends E> c) { |
1109 |
> |
rangeCheckForAdd(index); |
1110 |
> |
int cSize = c.size(); |
1111 |
> |
if (cSize==0) |
1112 |
> |
return false; |
1113 |
> |
checkForComodification(); |
1114 |
> |
root.addAll(offset + index, c); |
1115 |
> |
updateSizeAndModCount(cSize); |
1116 |
> |
return true; |
1117 |
> |
} |
1118 |
> |
|
1119 |
> |
public Iterator<E> iterator() { |
1120 |
> |
return listIterator(); |
1121 |
> |
} |
1122 |
> |
|
1123 |
> |
public ListIterator<E> listIterator(int index) { |
1124 |
> |
checkForComodification(); |
1125 |
> |
rangeCheckForAdd(index); |
1126 |
> |
|
1127 |
> |
return new ListIterator<E>() { |
1128 |
> |
int cursor = index; |
1129 |
> |
int lastRet = -1; |
1130 |
> |
int expectedModCount = root.modCount; |
1131 |
> |
|
1132 |
> |
public boolean hasNext() { |
1133 |
> |
return cursor != SubList.this.size; |
1134 |
> |
} |
1135 |
> |
|
1136 |
> |
@SuppressWarnings("unchecked") |
1137 |
> |
public E next() { |
1138 |
> |
checkForComodification(); |
1139 |
> |
int i = cursor; |
1140 |
> |
if (i >= SubList.this.size) |
1141 |
> |
throw new NoSuchElementException(); |
1142 |
> |
Object[] elementData = root.elementData; |
1143 |
> |
if (offset + i >= elementData.length) |
1144 |
> |
throw new ConcurrentModificationException(); |
1145 |
> |
cursor = i + 1; |
1146 |
> |
return (E) elementData[offset + (lastRet = i)]; |
1147 |
> |
} |
1148 |
> |
|
1149 |
> |
public boolean hasPrevious() { |
1150 |
> |
return cursor != 0; |
1151 |
> |
} |
1152 |
> |
|
1153 |
> |
@SuppressWarnings("unchecked") |
1154 |
> |
public E previous() { |
1155 |
> |
checkForComodification(); |
1156 |
> |
int i = cursor - 1; |
1157 |
> |
if (i < 0) |
1158 |
> |
throw new NoSuchElementException(); |
1159 |
> |
Object[] elementData = root.elementData; |
1160 |
> |
if (offset + i >= elementData.length) |
1161 |
> |
throw new ConcurrentModificationException(); |
1162 |
> |
cursor = i; |
1163 |
> |
return (E) elementData[offset + (lastRet = i)]; |
1164 |
> |
} |
1165 |
> |
|
1166 |
> |
@SuppressWarnings("unchecked") |
1167 |
> |
public void forEachRemaining(Consumer<? super E> consumer) { |
1168 |
> |
Objects.requireNonNull(consumer); |
1169 |
> |
final int size = SubList.this.size; |
1170 |
> |
int i = cursor; |
1171 |
> |
if (i >= size) { |
1172 |
> |
return; |
1173 |
> |
} |
1174 |
> |
final Object[] elementData = root.elementData; |
1175 |
> |
if (offset + i >= elementData.length) { |
1176 |
> |
throw new ConcurrentModificationException(); |
1177 |
> |
} |
1178 |
> |
while (i != size && modCount == expectedModCount) { |
1179 |
> |
consumer.accept((E) elementData[offset + (i++)]); |
1180 |
> |
} |
1181 |
> |
// update once at end of iteration to reduce heap write traffic |
1182 |
> |
lastRet = cursor = i; |
1183 |
> |
checkForComodification(); |
1184 |
> |
} |
1185 |
> |
|
1186 |
> |
public int nextIndex() { |
1187 |
> |
return cursor; |
1188 |
> |
} |
1189 |
> |
|
1190 |
> |
public int previousIndex() { |
1191 |
> |
return cursor - 1; |
1192 |
> |
} |
1193 |
> |
|
1194 |
> |
public void remove() { |
1195 |
> |
if (lastRet < 0) |
1196 |
> |
throw new IllegalStateException(); |
1197 |
> |
checkForComodification(); |
1198 |
> |
|
1199 |
> |
try { |
1200 |
> |
SubList.this.remove(lastRet); |
1201 |
> |
cursor = lastRet; |
1202 |
> |
lastRet = -1; |
1203 |
> |
expectedModCount = root.modCount; |
1204 |
> |
} catch (IndexOutOfBoundsException ex) { |
1205 |
> |
throw new ConcurrentModificationException(); |
1206 |
> |
} |
1207 |
> |
} |
1208 |
> |
|
1209 |
> |
public void set(E e) { |
1210 |
> |
if (lastRet < 0) |
1211 |
> |
throw new IllegalStateException(); |
1212 |
> |
checkForComodification(); |
1213 |
> |
|
1214 |
> |
try { |
1215 |
> |
root.set(offset + lastRet, e); |
1216 |
> |
} catch (IndexOutOfBoundsException ex) { |
1217 |
> |
throw new ConcurrentModificationException(); |
1218 |
> |
} |
1219 |
> |
} |
1220 |
> |
|
1221 |
> |
public void add(E e) { |
1222 |
> |
checkForComodification(); |
1223 |
> |
|
1224 |
> |
try { |
1225 |
> |
int i = cursor; |
1226 |
> |
SubList.this.add(i, e); |
1227 |
> |
cursor = i + 1; |
1228 |
> |
lastRet = -1; |
1229 |
> |
expectedModCount = root.modCount; |
1230 |
> |
} catch (IndexOutOfBoundsException ex) { |
1231 |
> |
throw new ConcurrentModificationException(); |
1232 |
> |
} |
1233 |
> |
} |
1234 |
> |
|
1235 |
> |
final void checkForComodification() { |
1236 |
> |
if (root.modCount != expectedModCount) |
1237 |
> |
throw new ConcurrentModificationException(); |
1238 |
> |
} |
1239 |
> |
}; |
1240 |
> |
} |
1241 |
> |
|
1242 |
> |
public List<E> subList(int fromIndex, int toIndex) { |
1243 |
> |
subListRangeCheck(fromIndex, toIndex, size); |
1244 |
> |
return new SubList<>(this, fromIndex, toIndex); |
1245 |
> |
} |
1246 |
> |
|
1247 |
> |
private void rangeCheckForAdd(int index) { |
1248 |
> |
if (index < 0 || index > this.size) |
1249 |
> |
throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); |
1250 |
> |
} |
1251 |
> |
|
1252 |
> |
private String outOfBoundsMsg(int index) { |
1253 |
> |
return "Index: "+index+", Size: "+this.size; |
1254 |
> |
} |
1255 |
> |
|
1256 |
> |
private void checkForComodification() { |
1257 |
> |
if (root.modCount != modCount) |
1258 |
> |
throw new ConcurrentModificationException(); |
1259 |
> |
} |
1260 |
> |
|
1261 |
> |
private void updateSizeAndModCount(int sizeChange) { |
1262 |
> |
SubList<E> slist = this; |
1263 |
> |
do { |
1264 |
> |
slist.size += sizeChange; |
1265 |
> |
slist.modCount = root.modCount; |
1266 |
> |
slist = slist.parent; |
1267 |
> |
} while (slist != null); |
1268 |
> |
} |
1269 |
> |
|
1270 |
> |
public Spliterator<E> spliterator() { |
1271 |
> |
checkForComodification(); |
1272 |
> |
|
1273 |
> |
// ArrayListSpliterator is not used because late-binding logic |
1274 |
> |
// is different here |
1275 |
> |
return new Spliterator<>() { |
1276 |
> |
private int index = offset; // current index, modified on advance/split |
1277 |
> |
private int fence = -1; // -1 until used; then one past last index |
1278 |
> |
private int expectedModCount; // initialized when fence set |
1279 |
> |
|
1280 |
> |
private int getFence() { // initialize fence to size on first use |
1281 |
> |
int hi; // (a specialized variant appears in method forEach) |
1282 |
> |
if ((hi = fence) < 0) { |
1283 |
> |
expectedModCount = modCount; |
1284 |
> |
hi = fence = offset + size; |
1285 |
> |
} |
1286 |
> |
return hi; |
1287 |
> |
} |
1288 |
> |
|
1289 |
> |
public ArrayListSpliterator<E> trySplit() { |
1290 |
> |
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1; |
1291 |
> |
// ArrayListSpliterator could be used here as the source is already bound |
1292 |
> |
return (lo >= mid) ? null : // divide range in half unless too small |
1293 |
> |
new ArrayListSpliterator<>(root, lo, index = mid, |
1294 |
> |
expectedModCount); |
1295 |
> |
} |
1296 |
> |
|
1297 |
> |
public boolean tryAdvance(Consumer<? super E> action) { |
1298 |
> |
Objects.requireNonNull(action); |
1299 |
> |
int hi = getFence(), i = index; |
1300 |
> |
if (i < hi) { |
1301 |
> |
index = i + 1; |
1302 |
> |
@SuppressWarnings("unchecked") E e = (E)root.elementData[i]; |
1303 |
> |
action.accept(e); |
1304 |
> |
if (root.modCount != expectedModCount) |
1305 |
> |
throw new ConcurrentModificationException(); |
1306 |
> |
return true; |
1307 |
> |
} |
1308 |
> |
return false; |
1309 |
> |
} |
1310 |
> |
|
1311 |
> |
public void forEachRemaining(Consumer<? super E> action) { |
1312 |
> |
Objects.requireNonNull(action); |
1313 |
> |
int i, hi, mc; // hoist accesses and checks from loop |
1314 |
> |
ArrayList<E> lst = root; |
1315 |
> |
Object[] a; |
1316 |
> |
if ((a = lst.elementData) != null) { |
1317 |
> |
if ((hi = fence) < 0) { |
1318 |
> |
mc = modCount; |
1319 |
> |
hi = offset + size; |
1320 |
> |
} |
1321 |
> |
else |
1322 |
> |
mc = expectedModCount; |
1323 |
> |
if ((i = index) >= 0 && (index = hi) <= a.length) { |
1324 |
> |
for (; i < hi; ++i) { |
1325 |
> |
@SuppressWarnings("unchecked") E e = (E) a[i]; |
1326 |
> |
action.accept(e); |
1327 |
> |
} |
1328 |
> |
if (lst.modCount == mc) |
1329 |
> |
return; |
1330 |
> |
} |
1331 |
> |
} |
1332 |
> |
throw new ConcurrentModificationException(); |
1333 |
> |
} |
1334 |
> |
|
1335 |
> |
public long estimateSize() { |
1336 |
> |
return (long) (getFence() - index); |
1337 |
> |
} |
1338 |
> |
|
1339 |
> |
public int characteristics() { |
1340 |
> |
return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED; |
1341 |
> |
} |
1342 |
> |
}; |
1343 |
> |
} |
1344 |
> |
} |
1345 |
> |
|
1346 |
> |
@Override |
1347 |
> |
public void forEach(Consumer<? super E> action) { |
1348 |
> |
Objects.requireNonNull(action); |
1349 |
> |
final int expectedModCount = modCount; |
1350 |
> |
@SuppressWarnings("unchecked") |
1351 |
> |
final E[] elementData = (E[]) this.elementData; |
1352 |
> |
final int size = this.size; |
1353 |
> |
for (int i=0; modCount == expectedModCount && i < size; i++) { |
1354 |
> |
action.accept(elementData[i]); |
1355 |
> |
} |
1356 |
> |
if (modCount != expectedModCount) { |
1357 |
> |
throw new ConcurrentModificationException(); |
1358 |
> |
} |
1359 |
> |
} |
1360 |
> |
|
1361 |
> |
/** |
1362 |
> |
* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em> |
1363 |
> |
* and <em>fail-fast</em> {@link Spliterator} over the elements in this |
1364 |
> |
* list. |
1365 |
> |
* |
1366 |
> |
* <p>The {@code Spliterator} reports {@link Spliterator#SIZED}, |
1367 |
> |
* {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}. |
1368 |
> |
* Overriding implementations should document the reporting of additional |
1369 |
> |
* characteristic values. |
1370 |
> |
* |
1371 |
> |
* @return a {@code Spliterator} over the elements in this list |
1372 |
> |
* @since 1.8 |
1373 |
> |
*/ |
1374 |
> |
@Override |
1375 |
> |
public Spliterator<E> spliterator() { |
1376 |
> |
return new ArrayListSpliterator<>(this, 0, -1, 0); |
1377 |
> |
} |
1378 |
> |
|
1379 |
> |
/** Index-based split-by-two, lazily initialized Spliterator */ |
1380 |
> |
static final class ArrayListSpliterator<E> implements Spliterator<E> { |
1381 |
> |
|
1382 |
> |
/* |
1383 |
> |
* If ArrayLists were immutable, or structurally immutable (no |
1384 |
> |
* adds, removes, etc), we could implement their spliterators |
1385 |
> |
* with Arrays.spliterator. Instead we detect as much |
1386 |
> |
* interference during traversal as practical without |
1387 |
> |
* sacrificing much performance. We rely primarily on |
1388 |
> |
* modCounts. These are not guaranteed to detect concurrency |
1389 |
> |
* violations, and are sometimes overly conservative about |
1390 |
> |
* within-thread interference, but detect enough problems to |
1391 |
> |
* be worthwhile in practice. To carry this out, we (1) lazily |
1392 |
> |
* initialize fence and expectedModCount until the latest |
1393 |
> |
* point that we need to commit to the state we are checking |
1394 |
> |
* against; thus improving precision. (This doesn't apply to |
1395 |
> |
* SubLists, that create spliterators with current non-lazy |
1396 |
> |
* values). (2) We perform only a single |
1397 |
> |
* ConcurrentModificationException check at the end of forEach |
1398 |
> |
* (the most performance-sensitive method). When using forEach |
1399 |
> |
* (as opposed to iterators), we can normally only detect |
1400 |
> |
* interference after actions, not before. Further |
1401 |
> |
* CME-triggering checks apply to all other possible |
1402 |
> |
* violations of assumptions for example null or too-small |
1403 |
> |
* elementData array given its size(), that could only have |
1404 |
> |
* occurred due to interference. This allows the inner loop |
1405 |
> |
* of forEach to run without any further checks, and |
1406 |
> |
* simplifies lambda-resolution. While this does entail a |
1407 |
> |
* number of checks, note that in the common case of |
1408 |
> |
* list.stream().forEach(a), no checks or other computation |
1409 |
> |
* occur anywhere other than inside forEach itself. The other |
1410 |
> |
* less-often-used methods cannot take advantage of most of |
1411 |
> |
* these streamlinings. |
1412 |
> |
*/ |
1413 |
> |
|
1414 |
> |
private final ArrayList<E> list; |
1415 |
> |
private int index; // current index, modified on advance/split |
1416 |
> |
private int fence; // -1 until used; then one past last index |
1417 |
> |
private int expectedModCount; // initialized when fence set |
1418 |
> |
|
1419 |
> |
/** Create new spliterator covering the given range */ |
1420 |
> |
ArrayListSpliterator(ArrayList<E> list, int origin, int fence, |
1421 |
> |
int expectedModCount) { |
1422 |
> |
this.list = list; // OK if null unless traversed |
1423 |
> |
this.index = origin; |
1424 |
> |
this.fence = fence; |
1425 |
> |
this.expectedModCount = expectedModCount; |
1426 |
> |
} |
1427 |
> |
|
1428 |
> |
private int getFence() { // initialize fence to size on first use |
1429 |
> |
int hi; // (a specialized variant appears in method forEach) |
1430 |
> |
ArrayList<E> lst; |
1431 |
> |
if ((hi = fence) < 0) { |
1432 |
> |
if ((lst = list) == null) |
1433 |
> |
hi = fence = 0; |
1434 |
> |
else { |
1435 |
> |
expectedModCount = lst.modCount; |
1436 |
> |
hi = fence = lst.size; |
1437 |
> |
} |
1438 |
> |
} |
1439 |
> |
return hi; |
1440 |
> |
} |
1441 |
> |
|
1442 |
> |
public ArrayListSpliterator<E> trySplit() { |
1443 |
> |
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1; |
1444 |
> |
return (lo >= mid) ? null : // divide range in half unless too small |
1445 |
> |
new ArrayListSpliterator<>(list, lo, index = mid, |
1446 |
> |
expectedModCount); |
1447 |
> |
} |
1448 |
> |
|
1449 |
> |
public boolean tryAdvance(Consumer<? super E> action) { |
1450 |
> |
if (action == null) |
1451 |
> |
throw new NullPointerException(); |
1452 |
> |
int hi = getFence(), i = index; |
1453 |
> |
if (i < hi) { |
1454 |
> |
index = i + 1; |
1455 |
> |
@SuppressWarnings("unchecked") E e = (E)list.elementData[i]; |
1456 |
> |
action.accept(e); |
1457 |
> |
if (list.modCount != expectedModCount) |
1458 |
> |
throw new ConcurrentModificationException(); |
1459 |
> |
return true; |
1460 |
> |
} |
1461 |
> |
return false; |
1462 |
> |
} |
1463 |
> |
|
1464 |
> |
public void forEachRemaining(Consumer<? super E> action) { |
1465 |
> |
int i, hi, mc; // hoist accesses and checks from loop |
1466 |
> |
ArrayList<E> lst; Object[] a; |
1467 |
> |
if (action == null) |
1468 |
> |
throw new NullPointerException(); |
1469 |
> |
if ((lst = list) != null && (a = lst.elementData) != null) { |
1470 |
> |
if ((hi = fence) < 0) { |
1471 |
> |
mc = lst.modCount; |
1472 |
> |
hi = lst.size; |
1473 |
> |
} |
1474 |
> |
else |
1475 |
> |
mc = expectedModCount; |
1476 |
> |
if ((i = index) >= 0 && (index = hi) <= a.length) { |
1477 |
> |
for (; i < hi; ++i) { |
1478 |
> |
@SuppressWarnings("unchecked") E e = (E) a[i]; |
1479 |
> |
action.accept(e); |
1480 |
> |
} |
1481 |
> |
if (lst.modCount == mc) |
1482 |
> |
return; |
1483 |
> |
} |
1484 |
> |
} |
1485 |
> |
throw new ConcurrentModificationException(); |
1486 |
> |
} |
1487 |
> |
|
1488 |
> |
public long estimateSize() { |
1489 |
> |
return (long) (getFence() - index); |
1490 |
> |
} |
1491 |
> |
|
1492 |
> |
public int characteristics() { |
1493 |
> |
return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED; |
1494 |
> |
} |
1495 |
> |
} |
1496 |
> |
|
1497 |
> |
@SuppressWarnings("unchecked") |
1498 |
> |
@Override |
1499 |
> |
public boolean removeIf(Predicate<? super E> filter) { |
1500 |
> |
Objects.requireNonNull(filter); |
1501 |
> |
int expectedModCount = modCount; |
1502 |
> |
final Object[] es = elementData; |
1503 |
> |
final int size = this.size; |
1504 |
> |
final boolean modified; |
1505 |
> |
int r; |
1506 |
> |
for (r = 0; r < size; r++) |
1507 |
> |
if (filter.test((E) es[r])) |
1508 |
> |
break; |
1509 |
> |
if (modified = (r < size)) { |
1510 |
> |
expectedModCount++; |
1511 |
> |
modCount++; |
1512 |
> |
int w = r++; |
1513 |
> |
try { |
1514 |
> |
for (E e; r < size; r++) |
1515 |
> |
if (!filter.test(e = (E) es[r])) |
1516 |
> |
es[w++] = e; |
1517 |
> |
Arrays.fill(es, (this.size = w), size, null); |
1518 |
> |
} catch (Throwable ex) { |
1519 |
> |
// copy remaining elements |
1520 |
> |
System.arraycopy(es, r, es, w, size - r); |
1521 |
> |
Arrays.fill(es, (this.size = w + size - r), size, null); |
1522 |
> |
throw ex; |
1523 |
> |
} |
1524 |
> |
} |
1525 |
> |
if (modCount != expectedModCount) |
1526 |
> |
throw new ConcurrentModificationException(); |
1527 |
> |
return modified; |
1528 |
> |
} |
1529 |
> |
|
1530 |
> |
@Override |
1531 |
> |
@SuppressWarnings("unchecked") |
1532 |
> |
public void replaceAll(UnaryOperator<E> operator) { |
1533 |
> |
Objects.requireNonNull(operator); |
1534 |
> |
final int expectedModCount = modCount; |
1535 |
> |
final int size = this.size; |
1536 |
> |
for (int i=0; modCount == expectedModCount && i < size; i++) { |
1537 |
> |
elementData[i] = operator.apply((E) elementData[i]); |
1538 |
> |
} |
1539 |
> |
if (modCount != expectedModCount) { |
1540 |
> |
throw new ConcurrentModificationException(); |
1541 |
> |
} |
1542 |
> |
modCount++; |
1543 |
> |
} |
1544 |
> |
|
1545 |
> |
@Override |
1546 |
> |
@SuppressWarnings("unchecked") |
1547 |
> |
public void sort(Comparator<? super E> c) { |
1548 |
> |
final int expectedModCount = modCount; |
1549 |
> |
Arrays.sort((E[]) elementData, 0, size, c); |
1550 |
> |
if (modCount != expectedModCount) { |
1551 |
> |
throw new ConcurrentModificationException(); |
1552 |
> |
} |
1553 |
> |
modCount++; |
1554 |
|
} |
1555 |
|
} |