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1 : dl 1.1 /*
2 : jsr166 1.30 * Copyright (c) 1994, 2013, Oracle and/or its affiliates. All rights reserved.
3 : jsr166 1.21 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 : dl 1.1 *
5 : jsr166 1.21 * 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 : jsr166 1.30 * published by the Free Software Foundation. Oracle designates this
8 : jsr166 1.21 * particular file as subject to the "Classpath" exception as provided
9 : jsr166 1.30 * by Oracle in the LICENSE file that accompanied this code.
10 : jsr166 1.21 *
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 : jsr166 1.27 * 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 : dl 1.1 */
25 :    
26 :     package java.util;
27 :    
28 : jsr166 1.30 import java.util.function.Consumer;
29 :     import java.util.function.Predicate;
30 :     import java.util.function.UnaryOperator;
31 :    
32 : dl 1.1 /**
33 : jsr166 1.14 * The {@code Vector} class implements a growable array of
34 : dl 1.1 * objects. Like an array, it contains components that can be
35 :     * accessed using an integer index. However, the size of a
36 : jsr166 1.14 * {@code Vector} can grow or shrink as needed to accommodate
37 :     * adding and removing items after the {@code Vector} has been created.
38 : dl 1.1 *
39 : jsr166 1.9 * <p>Each vector tries to optimize storage management by maintaining a
40 : jsr166 1.14 * {@code capacity} and a {@code capacityIncrement}. The
41 :     * {@code capacity} is always at least as large as the vector
42 : dl 1.1 * size; it is usually larger because as components are added to the
43 :     * vector, the vector's storage increases in chunks the size of
44 : jsr166 1.14 * {@code capacityIncrement}. An application can increase the
45 : dl 1.1 * capacity of a vector before inserting a large number of
46 : jsr166 1.9 * components; this reduces the amount of incremental reallocation.
47 : dl 1.1 *
48 : jsr166 1.30 * <p id="fail-fast">
49 : jsr166 1.22 * The iterators returned by this class's {@link #iterator() iterator} and
50 :     * {@link #listIterator(int) listIterator} methods are <em>fail-fast</em>:
51 :     * if the vector is structurally modified at any time after the iterator is
52 :     * created, in any way except through the iterator's own
53 :     * {@link ListIterator#remove() remove} or
54 :     * {@link ListIterator#add(Object) add} methods, the iterator will throw a
55 :     * {@link ConcurrentModificationException}. Thus, in the face of
56 :     * concurrent modification, the iterator fails quickly and cleanly, rather
57 :     * than risking arbitrary, non-deterministic behavior at an undetermined
58 :     * time in the future. The {@link Enumeration Enumerations} returned by
59 : jsr166 1.30 * the {@link #elements() elements} method are <em>not</em> fail-fast; if the
60 :     * Vector is structurally modified at any time after the enumeration is
61 :     * created then the results of enumerating are undefined.
62 : dl 1.1 *
63 :     * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
64 :     * as it is, generally speaking, impossible to make any hard guarantees in the
65 :     * presence of unsynchronized concurrent modification. Fail-fast iterators
66 : jsr166 1.14 * throw {@code ConcurrentModificationException} on a best-effort basis.
67 : dl 1.1 * Therefore, it would be wrong to write a program that depended on this
68 :     * exception for its correctness: <i>the fail-fast behavior of iterators
69 : jsr166 1.9 * should be used only to detect bugs.</i>
70 : dl 1.1 *
71 : jsr166 1.9 * <p>As of the Java 2 platform v1.2, this class was retrofitted to
72 :     * implement the {@link List} interface, making it a member of the
73 : jsr166 1.25 * <a href="{@docRoot}/../technotes/guides/collections/index.html">
74 :     * Java Collections Framework</a>. Unlike the new collection
75 :     * implementations, {@code Vector} is synchronized. If a thread-safe
76 :     * implementation is not needed, it is recommended to use {@link
77 :     * ArrayList} in place of {@code Vector}.
78 : dl 1.1 *
79 : jsr166 1.30 * @param <E> Type of component elements
80 :     *
81 : dl 1.1 * @author Lee Boynton
82 :     * @author Jonathan Payne
83 :     * @see Collection
84 :     * @see LinkedList
85 : jsr166 1.30 * @since 1.0
86 : dl 1.1 */
87 :     public class Vector<E>
88 :     extends AbstractList<E>
89 :     implements List<E>, RandomAccess, Cloneable, java.io.Serializable
90 :     {
91 :     /**
92 :     * The array buffer into which the components of the vector are
93 :     * stored. The capacity of the vector is the length of this array buffer,
94 : jsr166 1.15 * and is at least large enough to contain all the vector's elements.
95 : dl 1.1 *
96 : jsr166 1.15 * <p>Any array elements following the last element in the Vector are null.
97 : dl 1.1 *
98 :     * @serial
99 :     */
100 :     protected Object[] elementData;
101 :    
102 :     /**
103 : jsr166 1.14 * The number of valid components in this {@code Vector} object.
104 :     * Components {@code elementData[0]} through
105 :     * {@code elementData[elementCount-1]} are the actual items.
106 : dl 1.1 *
107 :     * @serial
108 :     */
109 :     protected int elementCount;
110 :    
111 :     /**
112 :     * The amount by which the capacity of the vector is automatically
113 :     * incremented when its size becomes greater than its capacity. If
114 :     * the capacity increment is less than or equal to zero, the capacity
115 :     * of the vector is doubled each time it needs to grow.
116 :     *
117 :     * @serial
118 :     */
119 :     protected int capacityIncrement;
120 :    
121 :     /** use serialVersionUID from JDK 1.0.2 for interoperability */
122 :     private static final long serialVersionUID = -2767605614048989439L;
123 :    
124 :     /**
125 :     * Constructs an empty vector with the specified initial capacity and
126 :     * capacity increment.
127 :     *
128 :     * @param initialCapacity the initial capacity of the vector
129 :     * @param capacityIncrement the amount by which the capacity is
130 :     * increased when the vector overflows
131 : jsr166 1.15 * @throws IllegalArgumentException if the specified initial capacity
132 :     * is negative
133 : dl 1.1 */
134 :     public Vector(int initialCapacity, int capacityIncrement) {
135 : jsr166 1.23 super();
136 : dl 1.1 if (initialCapacity < 0)
137 :     throw new IllegalArgumentException("Illegal Capacity: "+
138 :     initialCapacity);
139 : jsr166 1.23 this.elementData = new Object[initialCapacity];
140 :     this.capacityIncrement = capacityIncrement;
141 : dl 1.1 }
142 :    
143 :     /**
144 :     * Constructs an empty vector with the specified initial capacity and
145 :     * with its capacity increment equal to zero.
146 :     *
147 :     * @param initialCapacity the initial capacity of the vector
148 : jsr166 1.15 * @throws IllegalArgumentException if the specified initial capacity
149 :     * is negative
150 : dl 1.1 */
151 :     public Vector(int initialCapacity) {
152 : jsr166 1.23 this(initialCapacity, 0);
153 : dl 1.1 }
154 :    
155 :     /**
156 :     * Constructs an empty vector so that its internal data array
157 : jsr166 1.14 * has size {@code 10} and its standard capacity increment is
158 : dl 1.1 * zero.
159 :     */
160 :     public Vector() {
161 : jsr166 1.23 this(10);
162 : dl 1.1 }
163 :    
164 :     /**
165 :     * Constructs a vector containing the elements of the specified
166 :     * collection, in the order they are returned by the collection's
167 :     * iterator.
168 :     *
169 :     * @param c the collection whose elements are to be placed into this
170 :     * vector
171 :     * @throws NullPointerException if the specified collection is null
172 :     * @since 1.2
173 :     */
174 :     public Vector(Collection<? extends E> c) {
175 : jsr166 1.23 elementData = c.toArray();
176 :     elementCount = elementData.length;
177 : jsr166 1.30 // defend against c.toArray (incorrectly) not returning Object[]
178 :     // (see e.g. https://bugs.openjdk.java.net/browse/JDK-6260652)
179 : jsr166 1.23 if (elementData.getClass() != Object[].class)
180 :     elementData = Arrays.copyOf(elementData, elementCount, Object[].class);
181 : dl 1.1 }
182 :    
183 :     /**
184 :     * Copies the components of this vector into the specified array.
185 : jsr166 1.14 * The item at index {@code k} in this vector is copied into
186 :     * component {@code k} of {@code anArray}.
187 : dl 1.1 *
188 :     * @param anArray the array into which the components get copied
189 :     * @throws NullPointerException if the given array is null
190 :     * @throws IndexOutOfBoundsException if the specified array is not
191 :     * large enough to hold all the components of this vector
192 :     * @throws ArrayStoreException if a component of this vector is not of
193 :     * a runtime type that can be stored in the specified array
194 :     * @see #toArray(Object[])
195 :     */
196 :     public synchronized void copyInto(Object[] anArray) {
197 : jsr166 1.23 System.arraycopy(elementData, 0, anArray, 0, elementCount);
198 : dl 1.1 }
199 :    
200 :     /**
201 :     * Trims the capacity of this vector to be the vector's current
202 :     * size. If the capacity of this vector is larger than its current
203 :     * size, then the capacity is changed to equal the size by replacing
204 : jsr166 1.14 * its internal data array, kept in the field {@code elementData},
205 : dl 1.1 * with a smaller one. An application can use this operation to
206 :     * minimize the storage of a vector.
207 :     */
208 :     public synchronized void trimToSize() {
209 : jsr166 1.23 modCount++;
210 :     int oldCapacity = elementData.length;
211 :     if (elementCount < oldCapacity) {
212 : dl 1.1 elementData = Arrays.copyOf(elementData, elementCount);
213 : jsr166 1.23 }
214 : dl 1.1 }
215 :    
216 :     /**
217 :     * Increases the capacity of this vector, if necessary, to ensure
218 :     * that it can hold at least the number of components specified by
219 :     * the minimum capacity argument.
220 :     *
221 :     * <p>If the current capacity of this vector is less than
222 : jsr166 1.14 * {@code minCapacity}, then its capacity is increased by replacing its
223 :     * internal data array, kept in the field {@code elementData}, with a
224 : dl 1.1 * larger one. The size of the new data array will be the old size plus
225 : jsr166 1.14 * {@code capacityIncrement}, unless the value of
226 :     * {@code capacityIncrement} is less than or equal to zero, in which case
227 : dl 1.1 * the new capacity will be twice the old capacity; but if this new size
228 : jsr166 1.14 * is still smaller than {@code minCapacity}, then the new capacity will
229 :     * be {@code minCapacity}.
230 : dl 1.1 *
231 :     * @param minCapacity the desired minimum capacity
232 :     */
233 :     public synchronized void ensureCapacity(int minCapacity) {
234 : jsr166 1.30 if (minCapacity > 0) {
235 :     modCount++;
236 :     if (minCapacity > elementData.length)
237 :     grow(minCapacity);
238 :     }
239 :     }
240 :    
241 :     /**
242 :     * The maximum size of array to allocate (unless necessary).
243 :     * Some VMs reserve some header words in an array.
244 :     * Attempts to allocate larger arrays may result in
245 :     * OutOfMemoryError: Requested array size exceeds VM limit
246 :     */
247 :     private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
248 :    
249 :     /**
250 :     * Increases the capacity to ensure that it can hold at least the
251 :     * number of elements specified by the minimum capacity argument.
252 :     *
253 :     * @param minCapacity the desired minimum capacity
254 :     * @throws OutOfMemoryError if minCapacity is less than zero
255 :     */
256 :     private Object[] grow(int minCapacity) {
257 :     return elementData = Arrays.copyOf(elementData,
258 :     newCapacity(minCapacity));
259 :     }
260 :    
261 :     private Object[] grow() {
262 :     return grow(elementCount + 1);
263 : dl 1.1 }
264 :    
265 :     /**
266 : jsr166 1.30 * Returns a capacity at least as large as the given minimum capacity.
267 :     * Will not return a capacity greater than MAX_ARRAY_SIZE unless
268 :     * the given minimum capacity is greater than MAX_ARRAY_SIZE.
269 : dl 1.1 *
270 : jsr166 1.30 * @param minCapacity the desired minimum capacity
271 :     * @throws OutOfMemoryError if minCapacity is less than zero
272 : dl 1.1 */
273 : jsr166 1.30 private int newCapacity(int minCapacity) {
274 :     // overflow-conscious code
275 : jsr166 1.23 int oldCapacity = elementData.length;
276 : jsr166 1.30 int newCapacity = oldCapacity + ((capacityIncrement > 0) ?
277 :     capacityIncrement : oldCapacity);
278 :     if (newCapacity - minCapacity <= 0) {
279 :     if (minCapacity < 0) // overflow
280 :     throw new OutOfMemoryError();
281 :     return minCapacity;
282 :     }
283 :     return (newCapacity - MAX_ARRAY_SIZE <= 0)
284 :     ? newCapacity
285 :     : hugeCapacity(minCapacity);
286 :     }
287 :    
288 :     private static int hugeCapacity(int minCapacity) {
289 :     if (minCapacity < 0) // overflow
290 :     throw new OutOfMemoryError();
291 :     return (minCapacity > MAX_ARRAY_SIZE) ?
292 :     Integer.MAX_VALUE :
293 :     MAX_ARRAY_SIZE;
294 : dl 1.1 }
295 :    
296 :     /**
297 :     * Sets the size of this vector. If the new size is greater than the
298 : jsr166 1.14 * current size, new {@code null} items are added to the end of
299 : dl 1.1 * the vector. If the new size is less than the current size, all
300 : jsr166 1.14 * components at index {@code newSize} and greater are discarded.
301 : dl 1.1 *
302 : jsr166 1.16 * @param newSize the new size of this vector
303 :     * @throws ArrayIndexOutOfBoundsException if the new size is negative
304 : dl 1.1 */
305 :     public synchronized void setSize(int newSize) {
306 : jsr166 1.23 modCount++;
307 : jsr166 1.30 if (newSize > elementData.length)
308 :     grow(newSize);
309 :     for (int i = newSize; i < elementCount; i++)
310 :     elementData[i] = null;
311 : jsr166 1.23 elementCount = newSize;
312 : dl 1.1 }
313 :    
314 :     /**
315 :     * Returns the current capacity of this vector.
316 :     *
317 :     * @return the current capacity (the length of its internal
318 : jsr166 1.14 * data array, kept in the field {@code elementData}
319 : dl 1.1 * of this vector)
320 :     */
321 :     public synchronized int capacity() {
322 : jsr166 1.23 return elementData.length;
323 : dl 1.1 }
324 :    
325 :     /**
326 :     * Returns the number of components in this vector.
327 :     *
328 :     * @return the number of components in this vector
329 :     */
330 :     public synchronized int size() {
331 : jsr166 1.23 return elementCount;
332 : dl 1.1 }
333 :    
334 :     /**
335 :     * Tests if this vector has no components.
336 :     *
337 : jsr166 1.14 * @return {@code true} if and only if this vector has
338 : dl 1.1 * no components, that is, its size is zero;
339 : jsr166 1.14 * {@code false} otherwise.
340 : dl 1.1 */
341 :     public synchronized boolean isEmpty() {
342 : jsr166 1.23 return elementCount == 0;
343 : dl 1.1 }
344 :    
345 :     /**
346 :     * Returns an enumeration of the components of this vector. The
347 : jsr166 1.14 * returned {@code Enumeration} object will generate all items in
348 :     * this vector. The first item generated is the item at index {@code 0},
349 : jsr166 1.30 * then the item at index {@code 1}, and so on. If the vector is
350 :     * structurally modified while enumerating over the elements then the
351 :     * results of enumerating are undefined.
352 : dl 1.1 *
353 :     * @return an enumeration of the components of this vector
354 :     * @see Iterator
355 :     */
356 :     public Enumeration<E> elements() {
357 : jsr166 1.23 return new Enumeration<E>() {
358 :     int count = 0;
359 : dl 1.1
360 : jsr166 1.23 public boolean hasMoreElements() {
361 :     return count < elementCount;
362 :     }
363 :    
364 :     public E nextElement() {
365 :     synchronized (Vector.this) {
366 :     if (count < elementCount) {
367 :     return elementData(count++);
368 :     }
369 :     }
370 :     throw new NoSuchElementException("Vector Enumeration");
371 :     }
372 :     };
373 : dl 1.1 }
374 :    
375 :     /**
376 : jsr166 1.14 * Returns {@code true} if this vector contains the specified element.
377 :     * More formally, returns {@code true} if and only if this vector
378 :     * contains at least one element {@code e} such that
379 : jsr166 1.30 * {@code Objects.equals(o, e)}.
380 : dl 1.1 *
381 :     * @param o element whose presence in this vector is to be tested
382 : jsr166 1.14 * @return {@code true} if this vector contains the specified element
383 : dl 1.1 */
384 :     public boolean contains(Object o) {
385 : jsr166 1.23 return indexOf(o, 0) >= 0;
386 : dl 1.1 }
387 :    
388 :     /**
389 :     * Returns the index of the first occurrence of the specified element
390 :     * in this vector, or -1 if this vector does not contain the element.
391 : jsr166 1.14 * More formally, returns the lowest index {@code i} such that
392 : jsr166 1.30 * {@code Objects.equals(o, get(i))},
393 : dl 1.1 * or -1 if there is no such index.
394 :     *
395 :     * @param o element to search for
396 :     * @return the index of the first occurrence of the specified element in
397 :     * this vector, or -1 if this vector does not contain the element
398 :     */
399 :     public int indexOf(Object o) {
400 : jsr166 1.23 return indexOf(o, 0);
401 : dl 1.1 }
402 :    
403 :     /**
404 :     * Returns the index of the first occurrence of the specified element in
405 : jsr166 1.14 * this vector, searching forwards from {@code index}, or returns -1 if
406 : dl 1.1 * the element is not found.
407 : jsr166 1.14 * More formally, returns the lowest index {@code i} such that
408 : jsr166 1.30 * {@code (i >= index && Objects.equals(o, get(i)))},
409 : dl 1.1 * or -1 if there is no such index.
410 :     *
411 :     * @param o element to search for
412 :     * @param index index to start searching from
413 :     * @return the index of the first occurrence of the element in
414 : jsr166 1.14 * this vector at position {@code index} or later in the vector;
415 :     * {@code -1} if the element is not found.
416 : dl 1.1 * @throws IndexOutOfBoundsException if the specified index is negative
417 :     * @see Object#equals(Object)
418 :     */
419 :     public synchronized int indexOf(Object o, int index) {
420 : jsr166 1.23 if (o == null) {
421 :     for (int i = index ; i < elementCount ; i++)
422 :     if (elementData[i]==null)
423 :     return i;
424 :     } else {
425 :     for (int i = index ; i < elementCount ; i++)
426 :     if (o.equals(elementData[i]))
427 :     return i;
428 :     }
429 :     return -1;
430 : dl 1.1 }
431 :    
432 :     /**
433 :     * Returns the index of the last occurrence of the specified element
434 :     * in this vector, or -1 if this vector does not contain the element.
435 : jsr166 1.14 * More formally, returns the highest index {@code i} such that
436 : jsr166 1.30 * {@code Objects.equals(o, get(i))},
437 : dl 1.1 * or -1 if there is no such index.
438 :     *
439 :     * @param o element to search for
440 :     * @return the index of the last occurrence of the specified element in
441 :     * this vector, or -1 if this vector does not contain the element
442 :     */
443 :     public synchronized int lastIndexOf(Object o) {
444 : jsr166 1.23 return lastIndexOf(o, elementCount-1);
445 : dl 1.1 }
446 :    
447 :     /**
448 :     * Returns the index of the last occurrence of the specified element in
449 : jsr166 1.14 * this vector, searching backwards from {@code index}, or returns -1 if
450 : dl 1.1 * the element is not found.
451 : jsr166 1.14 * More formally, returns the highest index {@code i} such that
452 : jsr166 1.30 * {@code (i <= index && Objects.equals(o, get(i)))},
453 : dl 1.1 * or -1 if there is no such index.
454 :     *
455 :     * @param o element to search for
456 :     * @param index index to start searching backwards from
457 :     * @return the index of the last occurrence of the element at position
458 : jsr166 1.14 * less than or equal to {@code index} in this vector;
459 : dl 1.1 * -1 if the element is not found.
460 :     * @throws IndexOutOfBoundsException if the specified index is greater
461 :     * than or equal to the current size of this vector
462 :     */
463 :     public synchronized int lastIndexOf(Object o, int index) {
464 :     if (index >= elementCount)
465 :     throw new IndexOutOfBoundsException(index + " >= "+ elementCount);
466 :    
467 : jsr166 1.23 if (o == null) {
468 :     for (int i = index; i >= 0; i--)
469 :     if (elementData[i]==null)
470 :     return i;
471 :     } else {
472 :     for (int i = index; i >= 0; i--)
473 :     if (o.equals(elementData[i]))
474 :     return i;
475 :     }
476 :     return -1;
477 : dl 1.1 }
478 :    
479 :     /**
480 : jsr166 1.15 * Returns the component at the specified index.
481 : dl 1.1 *
482 : jsr166 1.15 * <p>This method is identical in functionality to the {@link #get(int)}
483 :     * method (which is part of the {@link List} interface).
484 : dl 1.1 *
485 :     * @param index an index into this vector
486 :     * @return the component at the specified index
487 : jsr166 1.15 * @throws ArrayIndexOutOfBoundsException if the index is out of range
488 : jsr166 1.23 * ({@code index < 0 || index >= size()})
489 : dl 1.1 */
490 :     public synchronized E elementAt(int index) {
491 : jsr166 1.23 if (index >= elementCount) {
492 :     throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
493 :     }
494 : dl 1.1
495 : jsr166 1.22 return elementData(index);
496 : dl 1.1 }
497 :    
498 :     /**
499 : jsr166 1.14 * Returns the first component (the item at index {@code 0}) of
500 : dl 1.1 * this vector.
501 :     *
502 :     * @return the first component of this vector
503 : jsr166 1.15 * @throws NoSuchElementException if this vector has no components
504 : dl 1.1 */
505 :     public synchronized E firstElement() {
506 : jsr166 1.23 if (elementCount == 0) {
507 :     throw new NoSuchElementException();
508 :     }
509 :     return elementData(0);
510 : dl 1.1 }
511 :    
512 :     /**
513 :     * Returns the last component of the vector.
514 :     *
515 :     * @return the last component of the vector, i.e., the component at index
516 : jsr166 1.31 * {@code size() - 1}
517 : jsr166 1.15 * @throws NoSuchElementException if this vector is empty
518 : dl 1.1 */
519 :     public synchronized E lastElement() {
520 : jsr166 1.23 if (elementCount == 0) {
521 :     throw new NoSuchElementException();
522 :     }
523 :     return elementData(elementCount - 1);
524 : dl 1.1 }
525 :    
526 :     /**
527 : jsr166 1.14 * Sets the component at the specified {@code index} of this
528 : dl 1.1 * vector to be the specified object. The previous component at that
529 : jsr166 1.16 * position is discarded.
530 : dl 1.1 *
531 : jsr166 1.16 * <p>The index must be a value greater than or equal to {@code 0}
532 :     * and less than the current size of the vector.
533 : dl 1.1 *
534 : jsr166 1.17 * <p>This method is identical in functionality to the
535 :     * {@link #set(int, Object) set(int, E)}
536 :     * method (which is part of the {@link List} interface). Note that the
537 :     * {@code set} method reverses the order of the parameters, to more closely
538 :     * match array usage. Note also that the {@code set} method returns the
539 :     * old value that was stored at the specified position.
540 : dl 1.1 *
541 :     * @param obj what the component is to be set to
542 :     * @param index the specified index
543 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
544 : jsr166 1.23 * ({@code index < 0 || index >= size()})
545 : dl 1.1 */
546 :     public synchronized void setElementAt(E obj, int index) {
547 : jsr166 1.23 if (index >= elementCount) {
548 :     throw new ArrayIndexOutOfBoundsException(index + " >= " +
549 :     elementCount);
550 :     }
551 :     elementData[index] = obj;
552 : dl 1.1 }
553 :    
554 :     /**
555 :     * Deletes the component at the specified index. Each component in
556 :     * this vector with an index greater or equal to the specified
557 : jsr166 1.14 * {@code index} is shifted downward to have an index one
558 : dl 1.1 * smaller than the value it had previously. The size of this vector
559 : jsr166 1.15 * is decreased by {@code 1}.
560 : dl 1.1 *
561 : jsr166 1.15 * <p>The index must be a value greater than or equal to {@code 0}
562 :     * and less than the current size of the vector.
563 : dl 1.1 *
564 : jsr166 1.17 * <p>This method is identical in functionality to the {@link #remove(int)}
565 :     * method (which is part of the {@link List} interface). Note that the
566 :     * {@code remove} method returns the old value that was stored at the
567 :     * specified position.
568 : dl 1.1 *
569 :     * @param index the index of the object to remove
570 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
571 : jsr166 1.23 * ({@code index < 0 || index >= size()})
572 : dl 1.1 */
573 :     public synchronized void removeElementAt(int index) {
574 : jsr166 1.23 if (index >= elementCount) {
575 :     throw new ArrayIndexOutOfBoundsException(index + " >= " +
576 :     elementCount);
577 :     }
578 :     else if (index < 0) {
579 :     throw new ArrayIndexOutOfBoundsException(index);
580 :     }
581 :     int j = elementCount - index - 1;
582 :     if (j > 0) {
583 :     System.arraycopy(elementData, index + 1, elementData, index, j);
584 :     }
585 : jsr166 1.30 modCount++;
586 : jsr166 1.23 elementCount--;
587 :     elementData[elementCount] = null; /* to let gc do its work */
588 : dl 1.1 }
589 :    
590 :     /**
591 :     * Inserts the specified object as a component in this vector at the
592 : jsr166 1.14 * specified {@code index}. Each component in this vector with
593 :     * an index greater or equal to the specified {@code index} is
594 : dl 1.1 * shifted upward to have an index one greater than the value it had
595 : jsr166 1.15 * previously.
596 : dl 1.1 *
597 : jsr166 1.15 * <p>The index must be a value greater than or equal to {@code 0}
598 : dl 1.1 * and less than or equal to the current size of the vector. (If the
599 :     * index is equal to the current size of the vector, the new element
600 : jsr166 1.15 * is appended to the Vector.)
601 : dl 1.1 *
602 : jsr166 1.17 * <p>This method is identical in functionality to the
603 :     * {@link #add(int, Object) add(int, E)}
604 :     * method (which is part of the {@link List} interface). Note that the
605 :     * {@code add} method reverses the order of the parameters, to more closely
606 :     * match array usage.
607 : dl 1.1 *
608 :     * @param obj the component to insert
609 :     * @param index where to insert the new component
610 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
611 : jsr166 1.23 * ({@code index < 0 || index > size()})
612 : dl 1.1 */
613 :     public synchronized void insertElementAt(E obj, int index) {
614 : jsr166 1.23 if (index > elementCount) {
615 :     throw new ArrayIndexOutOfBoundsException(index
616 :     + " > " + elementCount);
617 :     }
618 : jsr166 1.30 modCount++;
619 :     final int s = elementCount;
620 :     Object[] elementData = this.elementData;
621 :     if (s == elementData.length)
622 :     elementData = grow();
623 :     System.arraycopy(elementData, index,
624 :     elementData, index + 1,
625 :     s - index);
626 : jsr166 1.23 elementData[index] = obj;
627 : jsr166 1.30 elementCount = s + 1;
628 : dl 1.1 }
629 :    
630 :     /**
631 :     * Adds the specified component to the end of this vector,
632 :     * increasing its size by one. The capacity of this vector is
633 : jsr166 1.16 * increased if its size becomes greater than its capacity.
634 : dl 1.1 *
635 : jsr166 1.17 * <p>This method is identical in functionality to the
636 : jsr166 1.18 * {@link #add(Object) add(E)}
637 :     * method (which is part of the {@link List} interface).
638 : dl 1.1 *
639 :     * @param obj the component to be added
640 :     */
641 :     public synchronized void addElement(E obj) {
642 : jsr166 1.23 modCount++;
643 : jsr166 1.30 add(obj, elementData, elementCount);
644 : dl 1.1 }
645 :    
646 :     /**
647 :     * Removes the first (lowest-indexed) occurrence of the argument
648 :     * from this vector. If the object is found in this vector, each
649 :     * component in the vector with an index greater or equal to the
650 :     * object's index is shifted downward to have an index one smaller
651 : jsr166 1.16 * than the value it had previously.
652 : dl 1.1 *
653 : jsr166 1.18 * <p>This method is identical in functionality to the
654 :     * {@link #remove(Object)} method (which is part of the
655 :     * {@link List} interface).
656 : dl 1.1 *
657 :     * @param obj the component to be removed
658 : jsr166 1.14 * @return {@code true} if the argument was a component of this
659 :     * vector; {@code false} otherwise.
660 : dl 1.1 */
661 :     public synchronized boolean removeElement(Object obj) {
662 : jsr166 1.23 modCount++;
663 :     int i = indexOf(obj);
664 :     if (i >= 0) {
665 :     removeElementAt(i);
666 :     return true;
667 :     }
668 :     return false;
669 : dl 1.1 }
670 :    
671 :     /**
672 : jsr166 1.17 * Removes all components from this vector and sets its size to zero.
673 : dl 1.1 *
674 : jsr166 1.17 * <p>This method is identical in functionality to the {@link #clear}
675 :     * method (which is part of the {@link List} interface).
676 : dl 1.1 */
677 :     public synchronized void removeAllElements() {
678 : jsr166 1.23 // Let gc do its work
679 :     for (int i = 0; i < elementCount; i++)
680 :     elementData[i] = null;
681 : dl 1.1
682 : jsr166 1.30 modCount++;
683 : jsr166 1.23 elementCount = 0;
684 : dl 1.1 }
685 :    
686 :     /**
687 :     * Returns a clone of this vector. The copy will contain a
688 :     * reference to a clone of the internal data array, not a reference
689 : jsr166 1.14 * to the original internal data array of this {@code Vector} object.
690 : dl 1.1 *
691 :     * @return a clone of this vector
692 :     */
693 :     public synchronized Object clone() {
694 : jsr166 1.23 try {
695 :     @SuppressWarnings("unchecked")
696 :     Vector<E> v = (Vector<E>) super.clone();
697 :     v.elementData = Arrays.copyOf(elementData, elementCount);
698 :     v.modCount = 0;
699 :     return v;
700 :     } catch (CloneNotSupportedException e) {
701 :     // this shouldn't happen, since we are Cloneable
702 : jsr166 1.30 throw new InternalError(e);
703 : jsr166 1.23 }
704 : dl 1.1 }
705 :    
706 :     /**
707 :     * Returns an array containing all of the elements in this Vector
708 :     * in the correct order.
709 :     *
710 :     * @since 1.2
711 :     */
712 :     public synchronized Object[] toArray() {
713 :     return Arrays.copyOf(elementData, elementCount);
714 :     }
715 :    
716 :     /**
717 :     * Returns an array containing all of the elements in this Vector in the
718 :     * correct order; the runtime type of the returned array is that of the
719 :     * specified array. If the Vector fits in the specified array, it is
720 :     * returned therein. Otherwise, a new array is allocated with the runtime
721 : jsr166 1.16 * type of the specified array and the size of this Vector.
722 : dl 1.1 *
723 : jsr166 1.16 * <p>If the Vector fits in the specified array with room to spare
724 : dl 1.1 * (i.e., the array has more elements than the Vector),
725 :     * the element in the array immediately following the end of the
726 :     * Vector is set to null. (This is useful in determining the length
727 :     * of the Vector <em>only</em> if the caller knows that the Vector
728 :     * does not contain any null elements.)
729 :     *
730 : jsr166 1.30 * @param <T> type of array elements. The same type as {@code <E>} or a
731 :     * supertype of {@code <E>}.
732 : dl 1.1 * @param a the array into which the elements of the Vector are to
733 : jsr166 1.23 * be stored, if it is big enough; otherwise, a new array of the
734 :     * same runtime type is allocated for this purpose.
735 : dl 1.1 * @return an array containing the elements of the Vector
736 : jsr166 1.30 * @throws ArrayStoreException if the runtime type of a, {@code <T>}, is not
737 :     * a supertype of the runtime type, {@code <E>}, of every element in this
738 :     * Vector
739 : dl 1.1 * @throws NullPointerException if the given array is null
740 :     * @since 1.2
741 :     */
742 : jsr166 1.22 @SuppressWarnings("unchecked")
743 : dl 1.1 public synchronized <T> T[] toArray(T[] a) {
744 :     if (a.length < elementCount)
745 :     return (T[]) Arrays.copyOf(elementData, elementCount, a.getClass());
746 :    
747 : jsr166 1.23 System.arraycopy(elementData, 0, a, 0, elementCount);
748 : dl 1.1
749 :     if (a.length > elementCount)
750 :     a[elementCount] = null;
751 :    
752 :     return a;
753 :     }
754 :    
755 :     // Positional Access Operations
756 :    
757 : jsr166 1.22 @SuppressWarnings("unchecked")
758 :     E elementData(int index) {
759 : jsr166 1.23 return (E) elementData[index];
760 : jsr166 1.22 }
761 :    
762 : jsr166 1.33 @SuppressWarnings("unchecked")
763 :     static <E> E elementAt(Object[] es, int index) {
764 :     return (E) es[index];
765 :     }
766 :    
767 : dl 1.1 /**
768 :     * Returns the element at the specified position in this Vector.
769 :     *
770 :     * @param index index of the element to return
771 :     * @return object at the specified index
772 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
773 :     * ({@code index < 0 || index >= size()})
774 : dl 1.1 * @since 1.2
775 :     */
776 :     public synchronized E get(int index) {
777 : jsr166 1.23 if (index >= elementCount)
778 :     throw new ArrayIndexOutOfBoundsException(index);
779 : dl 1.1
780 : jsr166 1.23 return elementData(index);
781 : dl 1.1 }
782 :    
783 :     /**
784 :     * Replaces the element at the specified position in this Vector with the
785 :     * specified element.
786 :     *
787 :     * @param index index of the element to replace
788 :     * @param element element to be stored at the specified position
789 :     * @return the element previously at the specified position
790 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
791 : jsr166 1.23 * ({@code index < 0 || index >= size()})
792 : dl 1.1 * @since 1.2
793 :     */
794 :     public synchronized E set(int index, E element) {
795 : jsr166 1.23 if (index >= elementCount)
796 :     throw new ArrayIndexOutOfBoundsException(index);
797 : dl 1.1
798 : jsr166 1.23 E oldValue = elementData(index);
799 :     elementData[index] = element;
800 :     return oldValue;
801 : dl 1.1 }
802 :    
803 :     /**
804 : jsr166 1.30 * This helper method split out from add(E) to keep method
805 :     * bytecode size under 35 (the -XX:MaxInlineSize default value),
806 :     * which helps when add(E) is called in a C1-compiled loop.
807 :     */
808 :     private void add(E e, Object[] elementData, int s) {
809 :     if (s == elementData.length)
810 :     elementData = grow();
811 :     elementData[s] = e;
812 :     elementCount = s + 1;
813 :     }
814 :    
815 :     /**
816 : dl 1.1 * Appends the specified element to the end of this Vector.
817 :     *
818 :     * @param e element to be appended to this Vector
819 : jsr166 1.14 * @return {@code true} (as specified by {@link Collection#add})
820 : dl 1.1 * @since 1.2
821 :     */
822 :     public synchronized boolean add(E e) {
823 : jsr166 1.23 modCount++;
824 : jsr166 1.30 add(e, elementData, elementCount);
825 : dl 1.1 return true;
826 :     }
827 :    
828 :     /**
829 :     * Removes the first occurrence of the specified element in this Vector
830 :     * If the Vector does not contain the element, it is unchanged. More
831 :     * formally, removes the element with the lowest index i such that
832 : jsr166 1.30 * {@code Objects.equals(o, get(i))} (if such
833 : dl 1.1 * an element exists).
834 :     *
835 :     * @param o element to be removed from this Vector, if present
836 :     * @return true if the Vector contained the specified element
837 :     * @since 1.2
838 :     */
839 :     public boolean remove(Object o) {
840 :     return removeElement(o);
841 :     }
842 :    
843 :     /**
844 :     * Inserts the specified element at the specified position in this Vector.
845 :     * Shifts the element currently at that position (if any) and any
846 :     * subsequent elements to the right (adds one to their indices).
847 :     *
848 :     * @param index index at which the specified element is to be inserted
849 :     * @param element element to be inserted
850 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
851 :     * ({@code index < 0 || index > size()})
852 : dl 1.1 * @since 1.2
853 :     */
854 :     public void add(int index, E element) {
855 :     insertElementAt(element, index);
856 :     }
857 :    
858 :     /**
859 :     * Removes the element at the specified position in this Vector.
860 :     * Shifts any subsequent elements to the left (subtracts one from their
861 :     * indices). Returns the element that was removed from the Vector.
862 :     *
863 : jsr166 1.31 * @param index the index of the element to be removed
864 :     * @return element that was removed
865 : jsr166 1.18 * @throws ArrayIndexOutOfBoundsException if the index is out of range
866 :     * ({@code index < 0 || index >= size()})
867 : dl 1.1 * @since 1.2
868 :     */
869 :     public synchronized E remove(int index) {
870 : jsr166 1.23 modCount++;
871 :     if (index >= elementCount)
872 :     throw new ArrayIndexOutOfBoundsException(index);
873 :     E oldValue = elementData(index);
874 :    
875 :     int numMoved = elementCount - index - 1;
876 :     if (numMoved > 0)
877 :     System.arraycopy(elementData, index+1, elementData, index,
878 :     numMoved);
879 :     elementData[--elementCount] = null; // Let gc do its work
880 : dl 1.1
881 : jsr166 1.23 return oldValue;
882 : dl 1.1 }
883 :    
884 :     /**
885 :     * Removes all of the elements from this Vector. The Vector will
886 :     * be empty after this call returns (unless it throws an exception).
887 :     *
888 :     * @since 1.2
889 :     */
890 :     public void clear() {
891 :     removeAllElements();
892 :     }
893 :    
894 :     // Bulk Operations
895 :    
896 :     /**
897 :     * Returns true if this Vector contains all of the elements in the
898 :     * specified Collection.
899 :     *
900 :     * @param c a collection whose elements will be tested for containment
901 :     * in this Vector
902 :     * @return true if this Vector contains all of the elements in the
903 : jsr166 1.23 * specified collection
904 : dl 1.1 * @throws NullPointerException if the specified collection is null
905 :     */
906 :     public synchronized boolean containsAll(Collection<?> c) {
907 :     return super.containsAll(c);
908 :     }
909 :    
910 :     /**
911 :     * Appends all of the elements in the specified Collection to the end of
912 :     * this Vector, in the order that they are returned by the specified
913 :     * Collection's Iterator. The behavior of this operation is undefined if
914 :     * the specified Collection is modified while the operation is in progress.
915 :     * (This implies that the behavior of this call is undefined if the
916 :     * specified Collection is this Vector, and this Vector is nonempty.)
917 :     *
918 :     * @param c elements to be inserted into this Vector
919 : jsr166 1.14 * @return {@code true} if this Vector changed as a result of the call
920 : dl 1.1 * @throws NullPointerException if the specified collection is null
921 :     * @since 1.2
922 :     */
923 : jsr166 1.30 public boolean addAll(Collection<? extends E> c) {
924 :     Object[] a = c.toArray();
925 : jsr166 1.23 modCount++;
926 : dl 1.1 int numNew = a.length;
927 : jsr166 1.30 if (numNew == 0)
928 :     return false;
929 :     synchronized (this) {
930 :     Object[] elementData = this.elementData;
931 :     final int s = elementCount;
932 :     if (numNew > elementData.length - s)
933 :     elementData = grow(s + numNew);
934 :     System.arraycopy(a, 0, elementData, s, numNew);
935 :     elementCount = s + numNew;
936 :     return true;
937 :     }
938 : dl 1.1 }
939 :    
940 :     /**
941 :     * Removes from this Vector all of its elements that are contained in the
942 :     * specified Collection.
943 :     *
944 :     * @param c a collection of elements to be removed from the Vector
945 :     * @return true if this Vector changed as a result of the call
946 :     * @throws ClassCastException if the types of one or more elements
947 :     * in this vector are incompatible with the specified
948 : jsr166 1.30 * collection
949 :     * (<a href="Collection.html#optional-restrictions">optional</a>)
950 : dl 1.1 * @throws NullPointerException if this vector contains one or more null
951 :     * elements and the specified collection does not support null
952 : jsr166 1.30 * elements
953 :     * (<a href="Collection.html#optional-restrictions">optional</a>),
954 :     * or if the specified collection is null
955 : dl 1.1 * @since 1.2
956 :     */
957 : jsr166 1.31 public boolean removeAll(Collection<?> c) {
958 :     Objects.requireNonNull(c);
959 :     return bulkRemove(e -> c.contains(e));
960 : dl 1.1 }
961 :    
962 :     /**
963 :     * Retains only the elements in this Vector that are contained in the
964 :     * specified Collection. In other words, removes from this Vector all
965 :     * of its elements that are not contained in the specified Collection.
966 :     *
967 :     * @param c a collection of elements to be retained in this Vector
968 :     * (all other elements are removed)
969 :     * @return true if this Vector changed as a result of the call
970 :     * @throws ClassCastException if the types of one or more elements
971 :     * in this vector are incompatible with the specified
972 : jsr166 1.30 * collection
973 :     * (<a href="Collection.html#optional-restrictions">optional</a>)
974 : dl 1.1 * @throws NullPointerException if this vector contains one or more null
975 :     * elements and the specified collection does not support null
976 : jsr166 1.30 * elements
977 :     * (<a href="Collection.html#optional-restrictions">optional</a>),
978 :     * or if the specified collection is null
979 : dl 1.1 * @since 1.2
980 :     */
981 : jsr166 1.31 public boolean retainAll(Collection<?> c) {
982 :     Objects.requireNonNull(c);
983 :     return bulkRemove(e -> !c.contains(e));
984 :     }
985 :    
986 :     @Override
987 :     public boolean removeIf(Predicate<? super E> filter) {
988 :     Objects.requireNonNull(filter);
989 :     return bulkRemove(filter);
990 :     }
991 :    
992 : jsr166 1.33 // A tiny bit set implementation
993 :    
994 :     private static long[] nBits(int n) {
995 :     return new long[((n - 1) >> 6) + 1];
996 :     }
997 :     private static void setBit(long[] bits, int i) {
998 :     bits[i >> 6] |= 1L << i;
999 :     }
1000 :     private static boolean isClear(long[] bits, int i) {
1001 :     return (bits[i >> 6] & (1L << i)) == 0;
1002 :     }
1003 :    
1004 : jsr166 1.31 private synchronized boolean bulkRemove(Predicate<? super E> filter) {
1005 :     int expectedModCount = modCount;
1006 :     final Object[] es = elementData;
1007 : jsr166 1.33 final int end = elementCount;
1008 : jsr166 1.31 final boolean modified;
1009 : jsr166 1.33 int i;
1010 : jsr166 1.31 // Optimize for initial run of survivors
1011 : jsr166 1.33 for (i = 0; i < end && !filter.test(elementAt(es, i)); i++)
1012 : jsr166 1.32 ;
1013 : jsr166 1.33 // Tolerate predicates that reentrantly access the collection for
1014 :     // read (but writers still get CME), so traverse once to find
1015 :     // elements to delete, a second pass to physically expunge.
1016 :     if (modified = (i < end)) {
1017 : jsr166 1.31 expectedModCount++;
1018 :     modCount++;
1019 : jsr166 1.33 final int beg = i;
1020 :     final long[] deathRow = nBits(end - beg);
1021 :     deathRow[0] = 1L; // set bit 0
1022 :     for (i = beg + 1; i < end; i++)
1023 :     if (filter.test(elementAt(es, i)))
1024 :     setBit(deathRow, i - beg);
1025 :     int w = beg;
1026 :     for (i = beg; i < end; i++)
1027 :     if (isClear(deathRow, i - beg))
1028 :     es[w++] = es[i];
1029 :     Arrays.fill(es, elementCount = w, end, null);
1030 : jsr166 1.31 }
1031 :     if (modCount != expectedModCount)
1032 :     throw new ConcurrentModificationException();
1033 :     return modified;
1034 : dl 1.1 }
1035 :    
1036 :     /**
1037 :     * Inserts all of the elements in the specified Collection into this
1038 :     * Vector at the specified position. Shifts the element currently at
1039 :     * that position (if any) and any subsequent elements to the right
1040 :     * (increases their indices). The new elements will appear in the Vector
1041 :     * in the order that they are returned by the specified Collection's
1042 :     * iterator.
1043 :     *
1044 :     * @param index index at which to insert the first element from the
1045 :     * specified collection
1046 :     * @param c elements to be inserted into this Vector
1047 : jsr166 1.14 * @return {@code true} if this Vector changed as a result of the call
1048 : jsr166 1.18 * @throws ArrayIndexOutOfBoundsException if the index is out of range
1049 :     * ({@code index < 0 || index > size()})
1050 : dl 1.1 * @throws NullPointerException if the specified collection is null
1051 :     * @since 1.2
1052 :     */
1053 :     public synchronized boolean addAll(int index, Collection<? extends E> c) {
1054 : jsr166 1.23 if (index < 0 || index > elementCount)
1055 :     throw new ArrayIndexOutOfBoundsException(index);
1056 : dl 1.1
1057 :     Object[] a = c.toArray();
1058 : jsr166 1.30 modCount++;
1059 : jsr166 1.23 int numNew = a.length;
1060 : jsr166 1.30 if (numNew == 0)
1061 :     return false;
1062 :     Object[] elementData = this.elementData;
1063 :     final int s = elementCount;
1064 :     if (numNew > elementData.length - s)
1065 :     elementData = grow(s + numNew);
1066 : dl 1.1
1067 : jsr166 1.30 int numMoved = s - index;
1068 : jsr166 1.23 if (numMoved > 0)
1069 : jsr166 1.30 System.arraycopy(elementData, index,
1070 :     elementData, index + numNew,
1071 : jsr166 1.23 numMoved);
1072 : dl 1.1 System.arraycopy(a, 0, elementData, index, numNew);
1073 : jsr166 1.30 elementCount = s + numNew;
1074 :     return true;
1075 : dl 1.1 }
1076 :    
1077 :     /**
1078 :     * Compares the specified Object with this Vector for equality. Returns
1079 :     * true if and only if the specified Object is also a List, both Lists
1080 :     * have the same size, and all corresponding pairs of elements in the two
1081 : jsr166 1.14 * Lists are <em>equal</em>. (Two elements {@code e1} and
1082 : jsr166 1.30 * {@code e2} are <em>equal</em> if {@code Objects.equals(e1, e2)}.)
1083 :     * In other words, two Lists are defined to be
1084 : dl 1.1 * equal if they contain the same elements in the same order.
1085 :     *
1086 :     * @param o the Object to be compared for equality with this Vector
1087 :     * @return true if the specified Object is equal to this Vector
1088 :     */
1089 :     public synchronized boolean equals(Object o) {
1090 :     return super.equals(o);
1091 :     }
1092 :    
1093 :     /**
1094 :     * Returns the hash code value for this Vector.
1095 :     */
1096 :     public synchronized int hashCode() {
1097 :     return super.hashCode();
1098 :     }
1099 :    
1100 :     /**
1101 :     * Returns a string representation of this Vector, containing
1102 :     * the String representation of each element.
1103 :     */
1104 :     public synchronized String toString() {
1105 :     return super.toString();
1106 :     }
1107 :    
1108 :     /**
1109 : jsr166 1.22 * Returns a view of the portion of this List between fromIndex,
1110 :     * inclusive, and toIndex, exclusive. (If fromIndex and toIndex are
1111 :     * equal, the returned List is empty.) The returned List is backed by this
1112 :     * List, so changes in the returned List are reflected in this List, and
1113 :     * vice-versa. The returned List supports all of the optional List
1114 :     * operations supported by this List.
1115 : dl 1.1 *
1116 : jsr166 1.22 * <p>This method eliminates the need for explicit range operations (of
1117 :     * the sort that commonly exist for arrays). Any operation that expects
1118 :     * a List can be used as a range operation by operating on a subList view
1119 :     * instead of a whole List. For example, the following idiom
1120 :     * removes a range of elements from a List:
1121 :     * <pre>
1122 : jsr166 1.23 * list.subList(from, to).clear();
1123 : jsr166 1.22 * </pre>
1124 :     * Similar idioms may be constructed for indexOf and lastIndexOf,
1125 :     * and all of the algorithms in the Collections class can be applied to
1126 :     * a subList.
1127 :     *
1128 :     * <p>The semantics of the List returned by this method become undefined if
1129 :     * the backing list (i.e., this List) is <i>structurally modified</i> in
1130 :     * any way other than via the returned List. (Structural modifications are
1131 :     * those that change the size of the List, or otherwise perturb it in such
1132 :     * a fashion that iterations in progress may yield incorrect results.)
1133 :     *
1134 :     * @param fromIndex low endpoint (inclusive) of the subList
1135 :     * @param toIndex high endpoint (exclusive) of the subList
1136 :     * @return a view of the specified range within this List
1137 :     * @throws IndexOutOfBoundsException if an endpoint index value is out of range
1138 :     * {@code (fromIndex < 0 || toIndex > size)}
1139 :     * @throws IllegalArgumentException if the endpoint indices are out of order
1140 : jsr166 1.23 * {@code (fromIndex > toIndex)}
1141 : jsr166 1.22 */
1142 :     public synchronized List<E> subList(int fromIndex, int toIndex) {
1143 :     return Collections.synchronizedList(super.subList(fromIndex, toIndex),
1144 :     this);
1145 :     }
1146 :    
1147 :     /**
1148 :     * Removes from this list all of the elements whose index is between
1149 :     * {@code fromIndex}, inclusive, and {@code toIndex}, exclusive.
1150 :     * Shifts any succeeding elements to the left (reduces their index).
1151 :     * This call shortens the list by {@code (toIndex - fromIndex)} elements.
1152 :     * (If {@code toIndex==fromIndex}, this operation has no effect.)
1153 : dl 1.1 */
1154 :     protected synchronized void removeRange(int fromIndex, int toIndex) {
1155 : jsr166 1.23 int numMoved = elementCount - toIndex;
1156 : dl 1.1 System.arraycopy(elementData, toIndex, elementData, fromIndex,
1157 :     numMoved);
1158 :    
1159 : jsr166 1.23 // Let gc do its work
1160 : jsr166 1.30 modCount++;
1161 : jsr166 1.23 int newElementCount = elementCount - (toIndex-fromIndex);
1162 :     while (elementCount != newElementCount)
1163 :     elementData[--elementCount] = null;
1164 : dl 1.1 }
1165 :    
1166 :     /**
1167 : jsr166 1.14 * Save the state of the {@code Vector} instance to a stream (that
1168 : jsr166 1.30 * is, serialize it).
1169 :     * This method performs synchronization to ensure the consistency
1170 :     * of the serialized data.
1171 :     */
1172 :     private void writeObject(java.io.ObjectOutputStream s)
1173 :     throws java.io.IOException {
1174 :     final java.io.ObjectOutputStream.PutField fields = s.putFields();
1175 :     final Object[] data;
1176 :     synchronized (this) {
1177 :     fields.put("capacityIncrement", capacityIncrement);
1178 :     fields.put("elementCount", elementCount);
1179 :     data = elementData.clone();
1180 :     }
1181 :     fields.put("elementData", data);
1182 :     s.writeFields();
1183 : dl 1.1 }
1184 :    
1185 :     /**
1186 : jsr166 1.22 * Returns a list iterator over the elements in this list (in proper
1187 : dl 1.1 * sequence), starting at the specified position in the list.
1188 : jsr166 1.22 * The specified index indicates the first element that would be
1189 :     * returned by an initial call to {@link ListIterator#next next}.
1190 :     * An initial call to {@link ListIterator#previous previous} would
1191 :     * return the element with the specified index minus one.
1192 :     *
1193 :     * <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>.
1194 : dl 1.1 *
1195 :     * @throws IndexOutOfBoundsException {@inheritDoc}
1196 :     */
1197 :     public synchronized ListIterator<E> listIterator(int index) {
1198 : jsr166 1.23 if (index < 0 || index > elementCount)
1199 : dl 1.1 throw new IndexOutOfBoundsException("Index: "+index);
1200 : jsr166 1.23 return new ListItr(index);
1201 : dl 1.1 }
1202 : jsr166 1.2
1203 : dl 1.1 /**
1204 : jsr166 1.22 * Returns a list iterator over the elements in this list (in proper
1205 :     * sequence).
1206 :     *
1207 :     * <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>.
1208 :     *
1209 :     * @see #listIterator(int)
1210 : dl 1.3 */
1211 :     public synchronized ListIterator<E> listIterator() {
1212 : jsr166 1.23 return new ListItr(0);
1213 : dl 1.3 }
1214 :    
1215 :     /**
1216 : dl 1.1 * Returns an iterator over the elements in this list in proper sequence.
1217 :     *
1218 : jsr166 1.22 * <p>The returned iterator is <a href="#fail-fast"><i>fail-fast</i></a>.
1219 :     *
1220 : dl 1.1 * @return an iterator over the elements in this list in proper sequence
1221 :     */
1222 :     public synchronized Iterator<E> iterator() {
1223 : jsr166 1.23 return new Itr();
1224 : dl 1.1 }
1225 :    
1226 :     /**
1227 : jsr166 1.22 * An optimized version of AbstractList.Itr
1228 : dl 1.10 */
1229 : jsr166 1.22 private class Itr implements Iterator<E> {
1230 : jsr166 1.23 int cursor; // index of next element to return
1231 :     int lastRet = -1; // index of last element returned; -1 if no such
1232 :     int expectedModCount = modCount;
1233 : jsr166 1.22
1234 : jsr166 1.23 public boolean hasNext() {
1235 : jsr166 1.22 // Racy but within spec, since modifications are checked
1236 :     // within or after synchronization in next/previous
1237 :     return cursor != elementCount;
1238 : jsr166 1.23 }
1239 :    
1240 :     public E next() {
1241 :     synchronized (Vector.this) {
1242 :     checkForComodification();
1243 :     int i = cursor;
1244 :     if (i >= elementCount)
1245 :     throw new NoSuchElementException();
1246 :     cursor = i + 1;
1247 :     return elementData(lastRet = i);
1248 :     }
1249 :     }
1250 : jsr166 1.22
1251 : jsr166 1.23 public void remove() {
1252 :     if (lastRet == -1)
1253 :     throw new IllegalStateException();
1254 :     synchronized (Vector.this) {
1255 :     checkForComodification();
1256 :     Vector.this.remove(lastRet);
1257 :     expectedModCount = modCount;
1258 : dl 1.10 }
1259 : jsr166 1.23 cursor = lastRet;
1260 :     lastRet = -1;
1261 :     }
1262 :    
1263 : jsr166 1.30 @Override
1264 :     public void forEachRemaining(Consumer<? super E> action) {
1265 :     Objects.requireNonNull(action);
1266 :     synchronized (Vector.this) {
1267 :     final int size = elementCount;
1268 :     int i = cursor;
1269 :     if (i >= size) {
1270 :     return;
1271 :     }
1272 :     @SuppressWarnings("unchecked")
1273 :     final E[] elementData = (E[]) Vector.this.elementData;
1274 :     if (i >= elementData.length) {
1275 :     throw new ConcurrentModificationException();
1276 :     }
1277 :     while (i != size && modCount == expectedModCount) {
1278 :     action.accept(elementData[i++]);
1279 :     }
1280 :     // update once at end of iteration to reduce heap write traffic
1281 :     cursor = i;
1282 :     lastRet = i - 1;
1283 :     checkForComodification();
1284 :     }
1285 :     }
1286 :    
1287 : jsr166 1.23 final void checkForComodification() {
1288 :     if (modCount != expectedModCount)
1289 :     throw new ConcurrentModificationException();
1290 :     }
1291 : dl 1.10 }
1292 :    
1293 :     /**
1294 : jsr166 1.22 * An optimized version of AbstractList.ListItr
1295 : dl 1.1 */
1296 : jsr166 1.22 final class ListItr extends Itr implements ListIterator<E> {
1297 : jsr166 1.23 ListItr(int index) {
1298 :     super();
1299 :     cursor = index;
1300 :     }
1301 :    
1302 :     public boolean hasPrevious() {
1303 :     return cursor != 0;
1304 :     }
1305 :    
1306 :     public int nextIndex() {
1307 :     return cursor;
1308 :     }
1309 :    
1310 :     public int previousIndex() {
1311 :     return cursor - 1;
1312 :     }
1313 :    
1314 :     public E previous() {
1315 :     synchronized (Vector.this) {
1316 :     checkForComodification();
1317 :     int i = cursor - 1;
1318 :     if (i < 0)
1319 :     throw new NoSuchElementException();
1320 :     cursor = i;
1321 :     return elementData(lastRet = i);
1322 :     }
1323 :     }
1324 :    
1325 :     public void set(E e) {
1326 :     if (lastRet == -1)
1327 :     throw new IllegalStateException();
1328 :     synchronized (Vector.this) {
1329 :     checkForComodification();
1330 :     Vector.this.set(lastRet, e);
1331 :     }
1332 :     }
1333 :    
1334 :     public void add(E e) {
1335 :     int i = cursor;
1336 :     synchronized (Vector.this) {
1337 :     checkForComodification();
1338 :     Vector.this.add(i, e);
1339 :     expectedModCount = modCount;
1340 :     }
1341 :     cursor = i + 1;
1342 :     lastRet = -1;
1343 :     }
1344 : dl 1.1 }
1345 : jsr166 1.30
1346 :     @Override
1347 :     public synchronized 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 elementCount = this.elementCount;
1353 :     for (int i=0; modCount == expectedModCount && i < elementCount; i++) {
1354 :     action.accept(elementData[i]);
1355 :     }
1356 :     if (modCount != expectedModCount) {
1357 :     throw new ConcurrentModificationException();
1358 :     }
1359 :     }
1360 :    
1361 :     @Override
1362 :     @SuppressWarnings("unchecked")
1363 :     public synchronized void replaceAll(UnaryOperator<E> operator) {
1364 :     Objects.requireNonNull(operator);
1365 :     final int expectedModCount = modCount;
1366 :     final int size = elementCount;
1367 :     for (int i=0; modCount == expectedModCount && i < size; i++) {
1368 :     elementData[i] = operator.apply((E) elementData[i]);
1369 :     }
1370 :     if (modCount != expectedModCount) {
1371 :     throw new ConcurrentModificationException();
1372 :     }
1373 :     modCount++;
1374 :     }
1375 :    
1376 :     @SuppressWarnings("unchecked")
1377 :     @Override
1378 :     public synchronized void sort(Comparator<? super E> c) {
1379 :     final int expectedModCount = modCount;
1380 :     Arrays.sort((E[]) elementData, 0, elementCount, c);
1381 :     if (modCount != expectedModCount) {
1382 :     throw new ConcurrentModificationException();
1383 :     }
1384 :     modCount++;
1385 :     }
1386 :    
1387 :     /**
1388 :     * Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
1389 :     * and <em>fail-fast</em> {@link Spliterator} over the elements in this
1390 :     * list.
1391 :     *
1392 :     * <p>The {@code Spliterator} reports {@link Spliterator#SIZED},
1393 :     * {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}.
1394 :     * Overriding implementations should document the reporting of additional
1395 :     * characteristic values.
1396 :     *
1397 :     * @return a {@code Spliterator} over the elements in this list
1398 :     * @since 1.8
1399 :     */
1400 :     @Override
1401 :     public Spliterator<E> spliterator() {
1402 :     return new VectorSpliterator<>(this, null, 0, -1, 0);
1403 :     }
1404 :    
1405 :     /** Similar to ArrayList Spliterator */
1406 :     static final class VectorSpliterator<E> implements Spliterator<E> {
1407 :     private final Vector<E> list;
1408 :     private Object[] array;
1409 :     private int index; // current index, modified on advance/split
1410 :     private int fence; // -1 until used; then one past last index
1411 :     private int expectedModCount; // initialized when fence set
1412 :    
1413 :     /** Create new spliterator covering the given range */
1414 :     VectorSpliterator(Vector<E> list, Object[] array, int origin, int fence,
1415 :     int expectedModCount) {
1416 :     this.list = list;
1417 :     this.array = array;
1418 :     this.index = origin;
1419 :     this.fence = fence;
1420 :     this.expectedModCount = expectedModCount;
1421 :     }
1422 :    
1423 :     private int getFence() { // initialize on first use
1424 :     int hi;
1425 :     if ((hi = fence) < 0) {
1426 : jsr166 1.31 synchronized (list) {
1427 : jsr166 1.30 array = list.elementData;
1428 :     expectedModCount = list.modCount;
1429 :     hi = fence = list.elementCount;
1430 :     }
1431 :     }
1432 :     return hi;
1433 :     }
1434 :    
1435 :     public Spliterator<E> trySplit() {
1436 :     int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1437 :     return (lo >= mid) ? null :
1438 :     new VectorSpliterator<>(list, array, lo, index = mid,
1439 :     expectedModCount);
1440 :     }
1441 :    
1442 :     @SuppressWarnings("unchecked")
1443 :     public boolean tryAdvance(Consumer<? super E> action) {
1444 :     int i;
1445 :     if (action == null)
1446 :     throw new NullPointerException();
1447 :     if (getFence() > (i = index)) {
1448 :     index = i + 1;
1449 :     action.accept((E)array[i]);
1450 :     if (list.modCount != expectedModCount)
1451 :     throw new ConcurrentModificationException();
1452 :     return true;
1453 :     }
1454 :     return false;
1455 :     }
1456 :    
1457 :     @SuppressWarnings("unchecked")
1458 :     public void forEachRemaining(Consumer<? super E> action) {
1459 :     int i, hi; // hoist accesses and checks from loop
1460 :     Vector<E> lst; Object[] a;
1461 :     if (action == null)
1462 :     throw new NullPointerException();
1463 :     if ((lst = list) != null) {
1464 :     if ((hi = fence) < 0) {
1465 : jsr166 1.31 synchronized (lst) {
1466 : jsr166 1.30 expectedModCount = lst.modCount;
1467 :     a = array = lst.elementData;
1468 :     hi = fence = lst.elementCount;
1469 :     }
1470 :     }
1471 :     else
1472 :     a = array;
1473 :     if (a != null && (i = index) >= 0 && (index = hi) <= a.length) {
1474 :     while (i < hi)
1475 :     action.accept((E) a[i++]);
1476 :     if (lst.modCount == expectedModCount)
1477 :     return;
1478 :     }
1479 :     }
1480 :     throw new ConcurrentModificationException();
1481 :     }
1482 :    
1483 :     public long estimateSize() {
1484 :     return getFence() - index;
1485 :     }
1486 :    
1487 :     public int characteristics() {
1488 :     return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1489 :     }
1490 :     }
1491 : dl 1.1 }

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