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1 : dl 1.1 /*
2 : jsr166 1.12 * %W% %E%
3 : dl 1.1 *
4 : jsr166 1.7 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
5 : dl 1.1 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
6 :     */
7 :    
8 :     package java.util;
9 :    
10 :     /**
11 : jsr166 1.14 * The {@code Vector} class implements a growable array of
12 : dl 1.1 * objects. Like an array, it contains components that can be
13 :     * accessed using an integer index. However, the size of a
14 : jsr166 1.14 * {@code Vector} can grow or shrink as needed to accommodate
15 :     * adding and removing items after the {@code Vector} has been created.
16 : dl 1.1 *
17 : jsr166 1.9 * <p>Each vector tries to optimize storage management by maintaining a
18 : jsr166 1.14 * {@code capacity} and a {@code capacityIncrement}. The
19 :     * {@code capacity} is always at least as large as the vector
20 : dl 1.1 * size; it is usually larger because as components are added to the
21 :     * vector, the vector's storage increases in chunks the size of
22 : jsr166 1.14 * {@code capacityIncrement}. An application can increase the
23 : dl 1.1 * capacity of a vector before inserting a large number of
24 : jsr166 1.9 * components; this reduces the amount of incremental reallocation.
25 : dl 1.1 *
26 : jsr166 1.9 * <p>The Iterators returned by Vector's iterator and listIterator
27 : dl 1.1 * methods are <em>fail-fast</em>: if the Vector is structurally modified
28 :     * at any time after the Iterator is created, in any way except through the
29 :     * Iterator's own remove or add methods, the Iterator will throw a
30 :     * ConcurrentModificationException. Thus, in the face of concurrent
31 :     * modification, the Iterator fails quickly and cleanly, rather than risking
32 :     * arbitrary, non-deterministic behavior at an undetermined time in the future.
33 :     * The Enumerations returned by Vector's elements method are <em>not</em>
34 :     * fail-fast.
35 :     *
36 :     * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
37 :     * as it is, generally speaking, impossible to make any hard guarantees in the
38 :     * presence of unsynchronized concurrent modification. Fail-fast iterators
39 : jsr166 1.14 * throw {@code ConcurrentModificationException} on a best-effort basis.
40 : dl 1.1 * Therefore, it would be wrong to write a program that depended on this
41 :     * exception for its correctness: <i>the fail-fast behavior of iterators
42 : jsr166 1.9 * should be used only to detect bugs.</i>
43 : dl 1.1 *
44 : jsr166 1.9 * <p>As of the Java 2 platform v1.2, this class was retrofitted to
45 :     * implement the {@link List} interface, making it a member of the
46 : jsr166 1.13 * <a href="{@docRoot}/../technotes/guides/collections/index.html"> Java
47 : jsr166 1.9 * Collections Framework</a>. Unlike the new collection
48 :     * implementations, {@code Vector} is synchronized.
49 : dl 1.1 *
50 :     * @author Lee Boynton
51 :     * @author Jonathan Payne
52 : jsr166 1.12 * @version %I%, %G%
53 : dl 1.1 * @see Collection
54 :     * @see List
55 :     * @see ArrayList
56 :     * @see LinkedList
57 :     * @since JDK1.0
58 :     */
59 :     public class Vector<E>
60 :     extends AbstractList<E>
61 :     implements List<E>, RandomAccess, Cloneable, java.io.Serializable
62 :     {
63 :     /**
64 :     * The array buffer into which the components of the vector are
65 :     * stored. The capacity of the vector is the length of this array buffer,
66 : jsr166 1.15 * and is at least large enough to contain all the vector's elements.
67 : dl 1.1 *
68 : jsr166 1.15 * <p>Any array elements following the last element in the Vector are null.
69 : dl 1.1 *
70 :     * @serial
71 :     */
72 :     protected Object[] elementData;
73 :    
74 :     /**
75 : jsr166 1.14 * The number of valid components in this {@code Vector} object.
76 :     * Components {@code elementData[0]} through
77 :     * {@code elementData[elementCount-1]} are the actual items.
78 : dl 1.1 *
79 :     * @serial
80 :     */
81 :     protected int elementCount;
82 :    
83 :     /**
84 :     * The amount by which the capacity of the vector is automatically
85 :     * incremented when its size becomes greater than its capacity. If
86 :     * the capacity increment is less than or equal to zero, the capacity
87 :     * of the vector is doubled each time it needs to grow.
88 :     *
89 :     * @serial
90 :     */
91 :     protected int capacityIncrement;
92 :    
93 :     /** use serialVersionUID from JDK 1.0.2 for interoperability */
94 :     private static final long serialVersionUID = -2767605614048989439L;
95 :    
96 :     /**
97 :     * Constructs an empty vector with the specified initial capacity and
98 :     * capacity increment.
99 :     *
100 :     * @param initialCapacity the initial capacity of the vector
101 :     * @param capacityIncrement the amount by which the capacity is
102 :     * increased when the vector overflows
103 : jsr166 1.15 * @throws IllegalArgumentException if the specified initial capacity
104 :     * is negative
105 : dl 1.1 */
106 :     public Vector(int initialCapacity, int capacityIncrement) {
107 :     super();
108 :     if (initialCapacity < 0)
109 :     throw new IllegalArgumentException("Illegal Capacity: "+
110 :     initialCapacity);
111 :     this.elementData = new Object[initialCapacity];
112 :     this.capacityIncrement = capacityIncrement;
113 :     }
114 :    
115 :     /**
116 :     * Constructs an empty vector with the specified initial capacity and
117 :     * with its capacity increment equal to zero.
118 :     *
119 :     * @param initialCapacity the initial capacity of the vector
120 : jsr166 1.15 * @throws IllegalArgumentException if the specified initial capacity
121 :     * is negative
122 : dl 1.1 */
123 :     public Vector(int initialCapacity) {
124 :     this(initialCapacity, 0);
125 :     }
126 :    
127 :     /**
128 :     * Constructs an empty vector so that its internal data array
129 : jsr166 1.14 * has size {@code 10} and its standard capacity increment is
130 : dl 1.1 * zero.
131 :     */
132 :     public Vector() {
133 :     this(10);
134 :     }
135 :    
136 :     /**
137 :     * Constructs a vector containing the elements of the specified
138 :     * collection, in the order they are returned by the collection's
139 :     * iterator.
140 :     *
141 :     * @param c the collection whose elements are to be placed into this
142 :     * vector
143 :     * @throws NullPointerException if the specified collection is null
144 :     * @since 1.2
145 :     */
146 :     public Vector(Collection<? extends E> c) {
147 : jsr166 1.6 elementData = c.toArray();
148 :     elementCount = elementData.length;
149 :     // c.toArray might (incorrectly) not return Object[] (see 6260652)
150 :     if (elementData.getClass() != Object[].class)
151 :     elementData = Arrays.copyOf(elementData, elementCount, Object[].class);
152 : dl 1.1 }
153 :    
154 :     /**
155 :     * Copies the components of this vector into the specified array.
156 : jsr166 1.14 * The item at index {@code k} in this vector is copied into
157 :     * component {@code k} of {@code anArray}.
158 : dl 1.1 *
159 :     * @param anArray the array into which the components get copied
160 :     * @throws NullPointerException if the given array is null
161 :     * @throws IndexOutOfBoundsException if the specified array is not
162 :     * large enough to hold all the components of this vector
163 :     * @throws ArrayStoreException if a component of this vector is not of
164 :     * a runtime type that can be stored in the specified array
165 :     * @see #toArray(Object[])
166 :     */
167 :     public synchronized void copyInto(Object[] anArray) {
168 :     System.arraycopy(elementData, 0, anArray, 0, elementCount);
169 :     }
170 :    
171 :     /**
172 :     * Trims the capacity of this vector to be the vector's current
173 :     * size. If the capacity of this vector is larger than its current
174 :     * size, then the capacity is changed to equal the size by replacing
175 : jsr166 1.14 * its internal data array, kept in the field {@code elementData},
176 : dl 1.1 * with a smaller one. An application can use this operation to
177 :     * minimize the storage of a vector.
178 :     */
179 :     public synchronized void trimToSize() {
180 :     modCount++;
181 :     int oldCapacity = elementData.length;
182 :     if (elementCount < oldCapacity) {
183 :     elementData = Arrays.copyOf(elementData, elementCount);
184 :     }
185 :     }
186 :    
187 :     /**
188 :     * Increases the capacity of this vector, if necessary, to ensure
189 :     * that it can hold at least the number of components specified by
190 :     * the minimum capacity argument.
191 :     *
192 :     * <p>If the current capacity of this vector is less than
193 : jsr166 1.14 * {@code minCapacity}, then its capacity is increased by replacing its
194 :     * internal data array, kept in the field {@code elementData}, with a
195 : dl 1.1 * larger one. The size of the new data array will be the old size plus
196 : jsr166 1.14 * {@code capacityIncrement}, unless the value of
197 :     * {@code capacityIncrement} is less than or equal to zero, in which case
198 : dl 1.1 * the new capacity will be twice the old capacity; but if this new size
199 : jsr166 1.14 * is still smaller than {@code minCapacity}, then the new capacity will
200 :     * be {@code minCapacity}.
201 : dl 1.1 *
202 :     * @param minCapacity the desired minimum capacity
203 :     */
204 :     public synchronized void ensureCapacity(int minCapacity) {
205 :     modCount++;
206 :     ensureCapacityHelper(minCapacity);
207 :     }
208 :    
209 :     /**
210 :     * This implements the unsynchronized semantics of ensureCapacity.
211 :     * Synchronized methods in this class can internally call this
212 :     * method for ensuring capacity without incurring the cost of an
213 :     * extra synchronization.
214 :     *
215 : jsr166 1.15 * @see #ensureCapacity(int)
216 : dl 1.1 */
217 :     private void ensureCapacityHelper(int minCapacity) {
218 :     int oldCapacity = elementData.length;
219 :     if (minCapacity > oldCapacity) {
220 :     Object[] oldData = elementData;
221 :     int newCapacity = (capacityIncrement > 0) ?
222 :     (oldCapacity + capacityIncrement) : (oldCapacity * 2);
223 :     if (newCapacity < minCapacity) {
224 :     newCapacity = minCapacity;
225 :     }
226 :     elementData = Arrays.copyOf(elementData, newCapacity);
227 :     }
228 :     }
229 :    
230 :     /**
231 :     * Sets the size of this vector. If the new size is greater than the
232 : jsr166 1.14 * current size, new {@code null} items are added to the end of
233 : dl 1.1 * the vector. If the new size is less than the current size, all
234 : jsr166 1.14 * components at index {@code newSize} and greater are discarded.
235 : dl 1.1 *
236 : jsr166 1.16 * @param newSize the new size of this vector
237 :     * @throws ArrayIndexOutOfBoundsException if the new size is negative
238 : dl 1.1 */
239 :     public synchronized void setSize(int newSize) {
240 :     modCount++;
241 :     if (newSize > elementCount) {
242 :     ensureCapacityHelper(newSize);
243 :     } else {
244 :     for (int i = newSize ; i < elementCount ; i++) {
245 :     elementData[i] = null;
246 :     }
247 :     }
248 :     elementCount = newSize;
249 :     }
250 :    
251 :     /**
252 :     * Returns the current capacity of this vector.
253 :     *
254 :     * @return the current capacity (the length of its internal
255 : jsr166 1.14 * data array, kept in the field {@code elementData}
256 : dl 1.1 * of this vector)
257 :     */
258 :     public synchronized int capacity() {
259 :     return elementData.length;
260 :     }
261 :    
262 :     /**
263 :     * Returns the number of components in this vector.
264 :     *
265 :     * @return the number of components in this vector
266 :     */
267 :     public synchronized int size() {
268 :     return elementCount;
269 :     }
270 :    
271 :     /**
272 :     * Tests if this vector has no components.
273 :     *
274 : jsr166 1.14 * @return {@code true} if and only if this vector has
275 : dl 1.1 * no components, that is, its size is zero;
276 : jsr166 1.14 * {@code false} otherwise.
277 : dl 1.1 */
278 :     public synchronized boolean isEmpty() {
279 :     return elementCount == 0;
280 :     }
281 :    
282 :     /**
283 :     * Returns an enumeration of the components of this vector. The
284 : jsr166 1.14 * returned {@code Enumeration} object will generate all items in
285 :     * this vector. The first item generated is the item at index {@code 0},
286 :     * then the item at index {@code 1}, and so on.
287 : dl 1.1 *
288 :     * @return an enumeration of the components of this vector
289 :     * @see Iterator
290 :     */
291 :     public Enumeration<E> elements() {
292 :     return new Enumeration<E>() {
293 :     int count = 0;
294 :    
295 :     public boolean hasMoreElements() {
296 :     return count < elementCount;
297 :     }
298 :    
299 :     public E nextElement() {
300 :     synchronized (Vector.this) {
301 :     if (count < elementCount) {
302 :     return (E)elementData[count++];
303 :     }
304 :     }
305 :     throw new NoSuchElementException("Vector Enumeration");
306 :     }
307 :     };
308 :     }
309 :    
310 :     /**
311 : jsr166 1.14 * Returns {@code true} if this vector contains the specified element.
312 :     * More formally, returns {@code true} if and only if this vector
313 :     * contains at least one element {@code e} such that
314 : dl 1.1 * <tt>(o==null&nbsp;?&nbsp;e==null&nbsp;:&nbsp;o.equals(e))</tt>.
315 :     *
316 :     * @param o element whose presence in this vector is to be tested
317 : jsr166 1.14 * @return {@code true} if this vector contains the specified element
318 : dl 1.1 */
319 :     public boolean contains(Object o) {
320 :     return indexOf(o, 0) >= 0;
321 :     }
322 :    
323 :     /**
324 :     * Returns the index of the first occurrence of the specified element
325 :     * in this vector, or -1 if this vector does not contain the element.
326 : jsr166 1.14 * More formally, returns the lowest index {@code i} such that
327 : dl 1.1 * <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
328 :     * or -1 if there is no such index.
329 :     *
330 :     * @param o element to search for
331 :     * @return the index of the first occurrence of the specified element in
332 :     * this vector, or -1 if this vector does not contain the element
333 :     */
334 :     public int indexOf(Object o) {
335 :     return indexOf(o, 0);
336 :     }
337 :    
338 :     /**
339 :     * Returns the index of the first occurrence of the specified element in
340 : jsr166 1.14 * this vector, searching forwards from {@code index}, or returns -1 if
341 : dl 1.1 * the element is not found.
342 : jsr166 1.14 * More formally, returns the lowest index {@code i} such that
343 : dl 1.1 * <tt>(i&nbsp;&gt;=&nbsp;index&nbsp;&amp;&amp;&nbsp;(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i))))</tt>,
344 :     * or -1 if there is no such index.
345 :     *
346 :     * @param o element to search for
347 :     * @param index index to start searching from
348 :     * @return the index of the first occurrence of the element in
349 : jsr166 1.14 * this vector at position {@code index} or later in the vector;
350 :     * {@code -1} if the element is not found.
351 : dl 1.1 * @throws IndexOutOfBoundsException if the specified index is negative
352 :     * @see Object#equals(Object)
353 :     */
354 :     public synchronized int indexOf(Object o, int index) {
355 :     if (o == null) {
356 :     for (int i = index ; i < elementCount ; i++)
357 :     if (elementData[i]==null)
358 :     return i;
359 :     } else {
360 :     for (int i = index ; i < elementCount ; i++)
361 :     if (o.equals(elementData[i]))
362 :     return i;
363 :     }
364 :     return -1;
365 :     }
366 :    
367 :     /**
368 :     * Returns the index of the last occurrence of the specified element
369 :     * in this vector, or -1 if this vector does not contain the element.
370 : jsr166 1.14 * More formally, returns the highest index {@code i} such that
371 : dl 1.1 * <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
372 :     * or -1 if there is no such index.
373 :     *
374 :     * @param o element to search for
375 :     * @return the index of the last occurrence of the specified element in
376 :     * this vector, or -1 if this vector does not contain the element
377 :     */
378 :     public synchronized int lastIndexOf(Object o) {
379 :     return lastIndexOf(o, elementCount-1);
380 :     }
381 :    
382 :     /**
383 :     * Returns the index of the last occurrence of the specified element in
384 : jsr166 1.14 * this vector, searching backwards from {@code index}, or returns -1 if
385 : dl 1.1 * the element is not found.
386 : jsr166 1.14 * More formally, returns the highest index {@code i} such that
387 : dl 1.1 * <tt>(i&nbsp;&lt;=&nbsp;index&nbsp;&amp;&amp;&nbsp;(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i))))</tt>,
388 :     * or -1 if there is no such index.
389 :     *
390 :     * @param o element to search for
391 :     * @param index index to start searching backwards from
392 :     * @return the index of the last occurrence of the element at position
393 : jsr166 1.14 * less than or equal to {@code index} in this vector;
394 : dl 1.1 * -1 if the element is not found.
395 :     * @throws IndexOutOfBoundsException if the specified index is greater
396 :     * than or equal to the current size of this vector
397 :     */
398 :     public synchronized int lastIndexOf(Object o, int index) {
399 :     if (index >= elementCount)
400 :     throw new IndexOutOfBoundsException(index + " >= "+ elementCount);
401 :    
402 :     if (o == null) {
403 :     for (int i = index; i >= 0; i--)
404 :     if (elementData[i]==null)
405 :     return i;
406 :     } else {
407 :     for (int i = index; i >= 0; i--)
408 :     if (o.equals(elementData[i]))
409 :     return i;
410 :     }
411 :     return -1;
412 :     }
413 :    
414 :     /**
415 : jsr166 1.15 * Returns the component at the specified index.
416 : dl 1.1 *
417 : jsr166 1.15 * <p>This method is identical in functionality to the {@link #get(int)}
418 :     * method (which is part of the {@link List} interface).
419 : dl 1.1 *
420 :     * @param index an index into this vector
421 :     * @return the component at the specified index
422 : jsr166 1.15 * @throws ArrayIndexOutOfBoundsException if the index is out of range
423 :     * ({@code index < 0 || index >= size()})
424 : dl 1.1 */
425 :     public synchronized E elementAt(int index) {
426 :     if (index >= elementCount) {
427 :     throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
428 :     }
429 :    
430 :     return (E)elementData[index];
431 :     }
432 :    
433 :     /**
434 : jsr166 1.14 * Returns the first component (the item at index {@code 0}) of
435 : dl 1.1 * this vector.
436 :     *
437 :     * @return the first component of this vector
438 : jsr166 1.15 * @throws NoSuchElementException if this vector has no components
439 : dl 1.1 */
440 :     public synchronized E firstElement() {
441 :     if (elementCount == 0) {
442 :     throw new NoSuchElementException();
443 :     }
444 :     return (E)elementData[0];
445 :     }
446 :    
447 :     /**
448 :     * Returns the last component of the vector.
449 :     *
450 :     * @return the last component of the vector, i.e., the component at index
451 :     * <code>size()&nbsp;-&nbsp;1</code>.
452 : jsr166 1.15 * @throws NoSuchElementException if this vector is empty
453 : dl 1.1 */
454 :     public synchronized E lastElement() {
455 :     if (elementCount == 0) {
456 :     throw new NoSuchElementException();
457 :     }
458 :     return (E)elementData[elementCount - 1];
459 :     }
460 :    
461 :     /**
462 : jsr166 1.14 * Sets the component at the specified {@code index} of this
463 : dl 1.1 * vector to be the specified object. The previous component at that
464 : jsr166 1.16 * position is discarded.
465 : dl 1.1 *
466 : jsr166 1.16 * <p>The index must be a value greater than or equal to {@code 0}
467 :     * and less than the current size of the vector.
468 : dl 1.1 *
469 : jsr166 1.17 * <p>This method is identical in functionality to the
470 :     * {@link #set(int, Object) set(int, E)}
471 :     * method (which is part of the {@link List} interface). Note that the
472 :     * {@code set} method reverses the order of the parameters, to more closely
473 :     * match array usage. Note also that the {@code set} method returns the
474 :     * old value that was stored at the specified position.
475 : dl 1.1 *
476 :     * @param obj what the component is to be set to
477 :     * @param index the specified index
478 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
479 :     * ({@code index < 0 || index >= size()})
480 : dl 1.1 */
481 :     public synchronized void setElementAt(E obj, int index) {
482 :     if (index >= elementCount) {
483 :     throw new ArrayIndexOutOfBoundsException(index + " >= " +
484 :     elementCount);
485 :     }
486 :     elementData[index] = obj;
487 :     }
488 :    
489 :     /**
490 :     * Deletes the component at the specified index. Each component in
491 :     * this vector with an index greater or equal to the specified
492 : jsr166 1.14 * {@code index} is shifted downward to have an index one
493 : dl 1.1 * smaller than the value it had previously. The size of this vector
494 : jsr166 1.15 * is decreased by {@code 1}.
495 : dl 1.1 *
496 : jsr166 1.15 * <p>The index must be a value greater than or equal to {@code 0}
497 :     * and less than the current size of the vector.
498 : dl 1.1 *
499 : jsr166 1.17 * <p>This method is identical in functionality to the {@link #remove(int)}
500 :     * method (which is part of the {@link List} interface). Note that the
501 :     * {@code remove} method returns the old value that was stored at the
502 :     * specified position.
503 : dl 1.1 *
504 :     * @param index the index of the object to remove
505 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
506 :     * ({@code index < 0 || index >= size()})
507 : dl 1.1 */
508 :     public synchronized void removeElementAt(int index) {
509 :     modCount++;
510 :     if (index >= elementCount) {
511 :     throw new ArrayIndexOutOfBoundsException(index + " >= " +
512 :     elementCount);
513 :     }
514 :     else if (index < 0) {
515 :     throw new ArrayIndexOutOfBoundsException(index);
516 :     }
517 :     int j = elementCount - index - 1;
518 :     if (j > 0) {
519 :     System.arraycopy(elementData, index + 1, elementData, index, j);
520 :     }
521 :     elementCount--;
522 :     elementData[elementCount] = null; /* to let gc do its work */
523 :     }
524 :    
525 :     /**
526 :     * Inserts the specified object as a component in this vector at the
527 : jsr166 1.14 * specified {@code index}. Each component in this vector with
528 :     * an index greater or equal to the specified {@code index} is
529 : dl 1.1 * shifted upward to have an index one greater than the value it had
530 : jsr166 1.15 * previously.
531 : dl 1.1 *
532 : jsr166 1.15 * <p>The index must be a value greater than or equal to {@code 0}
533 : dl 1.1 * and less than or equal to the current size of the vector. (If the
534 :     * index is equal to the current size of the vector, the new element
535 : jsr166 1.15 * is appended to the Vector.)
536 : dl 1.1 *
537 : jsr166 1.17 * <p>This method is identical in functionality to the
538 :     * {@link #add(int, Object) add(int, E)}
539 :     * method (which is part of the {@link List} interface). Note that the
540 :     * {@code add} method reverses the order of the parameters, to more closely
541 :     * match array usage.
542 : dl 1.1 *
543 :     * @param obj the component to insert
544 :     * @param index where to insert the new component
545 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
546 :     * ({@code index < 0 || index > size()})
547 : dl 1.1 */
548 :     public synchronized void insertElementAt(E obj, int index) {
549 :     modCount++;
550 :     if (index > elementCount) {
551 :     throw new ArrayIndexOutOfBoundsException(index
552 :     + " > " + elementCount);
553 :     }
554 :     ensureCapacityHelper(elementCount + 1);
555 :     System.arraycopy(elementData, index, elementData, index + 1, elementCount - index);
556 :     elementData[index] = obj;
557 :     elementCount++;
558 :     }
559 :    
560 :     /**
561 :     * Adds the specified component to the end of this vector,
562 :     * increasing its size by one. The capacity of this vector is
563 : jsr166 1.16 * increased if its size becomes greater than its capacity.
564 : dl 1.1 *
565 : jsr166 1.17 * <p>This method is identical in functionality to the
566 : jsr166 1.18 * {@link #add(Object) add(E)}
567 :     * method (which is part of the {@link List} interface).
568 : dl 1.1 *
569 :     * @param obj the component to be added
570 :     */
571 :     public synchronized void addElement(E obj) {
572 :     modCount++;
573 :     ensureCapacityHelper(elementCount + 1);
574 :     elementData[elementCount++] = obj;
575 :     }
576 :    
577 :     /**
578 :     * Removes the first (lowest-indexed) occurrence of the argument
579 :     * from this vector. If the object is found in this vector, each
580 :     * component in the vector with an index greater or equal to the
581 :     * object's index is shifted downward to have an index one smaller
582 : jsr166 1.16 * than the value it had previously.
583 : dl 1.1 *
584 : jsr166 1.18 * <p>This method is identical in functionality to the
585 :     * {@link #remove(Object)} method (which is part of the
586 :     * {@link List} interface).
587 : dl 1.1 *
588 :     * @param obj the component to be removed
589 : jsr166 1.14 * @return {@code true} if the argument was a component of this
590 :     * vector; {@code false} otherwise.
591 : dl 1.1 */
592 :     public synchronized boolean removeElement(Object obj) {
593 :     modCount++;
594 :     int i = indexOf(obj);
595 :     if (i >= 0) {
596 :     removeElementAt(i);
597 :     return true;
598 :     }
599 :     return false;
600 :     }
601 :    
602 :     /**
603 : jsr166 1.17 * Removes all components from this vector and sets its size to zero.
604 : dl 1.1 *
605 : jsr166 1.17 * <p>This method is identical in functionality to the {@link #clear}
606 :     * method (which is part of the {@link List} interface).
607 : dl 1.1 */
608 :     public synchronized void removeAllElements() {
609 :     modCount++;
610 :     // Let gc do its work
611 :     for (int i = 0; i < elementCount; i++)
612 :     elementData[i] = null;
613 :    
614 :     elementCount = 0;
615 :     }
616 :    
617 :     /**
618 :     * Returns a clone of this vector. The copy will contain a
619 :     * reference to a clone of the internal data array, not a reference
620 : jsr166 1.14 * to the original internal data array of this {@code Vector} object.
621 : dl 1.1 *
622 :     * @return a clone of this vector
623 :     */
624 :     public synchronized Object clone() {
625 :     try {
626 :     Vector<E> v = (Vector<E>) super.clone();
627 :     v.elementData = Arrays.copyOf(elementData, elementCount);
628 :     v.modCount = 0;
629 :     return v;
630 :     } catch (CloneNotSupportedException e) {
631 :     // this shouldn't happen, since we are Cloneable
632 :     throw new InternalError();
633 :     }
634 :     }
635 :    
636 :     /**
637 :     * Returns an array containing all of the elements in this Vector
638 :     * in the correct order.
639 :     *
640 :     * @since 1.2
641 :     */
642 :     public synchronized Object[] toArray() {
643 :     return Arrays.copyOf(elementData, elementCount);
644 :     }
645 :    
646 :     /**
647 :     * Returns an array containing all of the elements in this Vector in the
648 :     * correct order; the runtime type of the returned array is that of the
649 :     * specified array. If the Vector fits in the specified array, it is
650 :     * returned therein. Otherwise, a new array is allocated with the runtime
651 : jsr166 1.16 * type of the specified array and the size of this Vector.
652 : dl 1.1 *
653 : jsr166 1.16 * <p>If the Vector fits in the specified array with room to spare
654 : dl 1.1 * (i.e., the array has more elements than the Vector),
655 :     * the element in the array immediately following the end of the
656 :     * Vector is set to null. (This is useful in determining the length
657 :     * of the Vector <em>only</em> if the caller knows that the Vector
658 :     * does not contain any null elements.)
659 :     *
660 :     * @param a the array into which the elements of the Vector are to
661 :     * be stored, if it is big enough; otherwise, a new array of the
662 :     * same runtime type is allocated for this purpose.
663 :     * @return an array containing the elements of the Vector
664 : jsr166 1.17 * @throws ArrayStoreException if the runtime type of a is not a supertype
665 : dl 1.1 * of the runtime type of every element in this Vector
666 :     * @throws NullPointerException if the given array is null
667 :     * @since 1.2
668 :     */
669 :     public synchronized <T> T[] toArray(T[] a) {
670 :     if (a.length < elementCount)
671 :     return (T[]) Arrays.copyOf(elementData, elementCount, a.getClass());
672 :    
673 :     System.arraycopy(elementData, 0, a, 0, elementCount);
674 :    
675 :     if (a.length > elementCount)
676 :     a[elementCount] = null;
677 :    
678 :     return a;
679 :     }
680 :    
681 :     // Positional Access Operations
682 :    
683 :     /**
684 :     * Returns the element at the specified position in this Vector.
685 :     *
686 :     * @param index index of the element to return
687 :     * @return object at the specified index
688 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
689 :     * ({@code index < 0 || index >= size()})
690 : dl 1.1 * @since 1.2
691 :     */
692 :     public synchronized E get(int index) {
693 :     if (index >= elementCount)
694 :     throw new ArrayIndexOutOfBoundsException(index);
695 :    
696 :     return (E)elementData[index];
697 :     }
698 :    
699 :     /**
700 :     * Replaces the element at the specified position in this Vector with the
701 :     * specified element.
702 :     *
703 :     * @param index index of the element to replace
704 :     * @param element element to be stored at the specified position
705 :     * @return the element previously at the specified position
706 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
707 :     * ({@code index < 0 || index >= size()})
708 : dl 1.1 * @since 1.2
709 :     */
710 :     public synchronized E set(int index, E element) {
711 :     if (index >= elementCount)
712 :     throw new ArrayIndexOutOfBoundsException(index);
713 :    
714 :     Object oldValue = elementData[index];
715 :     elementData[index] = element;
716 :     return (E)oldValue;
717 :     }
718 :    
719 :     /**
720 :     * Appends the specified element to the end of this Vector.
721 :     *
722 :     * @param e element to be appended to this Vector
723 : jsr166 1.14 * @return {@code true} (as specified by {@link Collection#add})
724 : dl 1.1 * @since 1.2
725 :     */
726 :     public synchronized boolean add(E e) {
727 :     modCount++;
728 :     ensureCapacityHelper(elementCount + 1);
729 :     elementData[elementCount++] = e;
730 :     return true;
731 :     }
732 :    
733 :     /**
734 :     * Removes the first occurrence of the specified element in this Vector
735 :     * If the Vector does not contain the element, it is unchanged. More
736 :     * formally, removes the element with the lowest index i such that
737 : jsr166 1.14 * {@code (o==null ? get(i)==null : o.equals(get(i)))} (if such
738 : dl 1.1 * an element exists).
739 :     *
740 :     * @param o element to be removed from this Vector, if present
741 :     * @return true if the Vector contained the specified element
742 :     * @since 1.2
743 :     */
744 :     public boolean remove(Object o) {
745 :     return removeElement(o);
746 :     }
747 :    
748 :     /**
749 :     * Inserts the specified element at the specified position in this Vector.
750 :     * Shifts the element currently at that position (if any) and any
751 :     * subsequent elements to the right (adds one to their indices).
752 :     *
753 :     * @param index index at which the specified element is to be inserted
754 :     * @param element element to be inserted
755 : jsr166 1.17 * @throws ArrayIndexOutOfBoundsException if the index is out of range
756 :     * ({@code index < 0 || index > size()})
757 : dl 1.1 * @since 1.2
758 :     */
759 :     public void add(int index, E element) {
760 :     insertElementAt(element, index);
761 :     }
762 :    
763 :     /**
764 :     * Removes the element at the specified position in this Vector.
765 :     * Shifts any subsequent elements to the left (subtracts one from their
766 :     * indices). Returns the element that was removed from the Vector.
767 :     *
768 : jsr166 1.18 * @throws ArrayIndexOutOfBoundsException if the index is out of range
769 :     * ({@code index < 0 || index >= size()})
770 : dl 1.1 * @param index the index of the element to be removed
771 :     * @return element that was removed
772 :     * @since 1.2
773 :     */
774 :     public synchronized E remove(int index) {
775 :     modCount++;
776 :     if (index >= elementCount)
777 :     throw new ArrayIndexOutOfBoundsException(index);
778 :     Object oldValue = elementData[index];
779 :    
780 :     int numMoved = elementCount - index - 1;
781 :     if (numMoved > 0)
782 :     System.arraycopy(elementData, index+1, elementData, index,
783 :     numMoved);
784 :     elementData[--elementCount] = null; // Let gc do its work
785 :    
786 :     return (E)oldValue;
787 :     }
788 :    
789 :     /**
790 :     * Removes all of the elements from this Vector. The Vector will
791 :     * be empty after this call returns (unless it throws an exception).
792 :     *
793 :     * @since 1.2
794 :     */
795 :     public void clear() {
796 :     removeAllElements();
797 :     }
798 :    
799 :     // Bulk Operations
800 :    
801 :     /**
802 :     * Returns true if this Vector contains all of the elements in the
803 :     * specified Collection.
804 :     *
805 :     * @param c a collection whose elements will be tested for containment
806 :     * in this Vector
807 :     * @return true if this Vector contains all of the elements in the
808 :     * specified collection
809 :     * @throws NullPointerException if the specified collection is null
810 :     */
811 :     public synchronized boolean containsAll(Collection<?> c) {
812 :     return super.containsAll(c);
813 :     }
814 :    
815 :     /**
816 :     * Appends all of the elements in the specified Collection to the end of
817 :     * this Vector, in the order that they are returned by the specified
818 :     * Collection's Iterator. The behavior of this operation is undefined if
819 :     * the specified Collection is modified while the operation is in progress.
820 :     * (This implies that the behavior of this call is undefined if the
821 :     * specified Collection is this Vector, and this Vector is nonempty.)
822 :     *
823 :     * @param c elements to be inserted into this Vector
824 : jsr166 1.14 * @return {@code true} if this Vector changed as a result of the call
825 : dl 1.1 * @throws NullPointerException if the specified collection is null
826 :     * @since 1.2
827 :     */
828 :     public synchronized boolean addAll(Collection<? extends E> c) {
829 :     modCount++;
830 :     Object[] a = c.toArray();
831 :     int numNew = a.length;
832 :     ensureCapacityHelper(elementCount + numNew);
833 :     System.arraycopy(a, 0, elementData, elementCount, numNew);
834 :     elementCount += numNew;
835 :     return numNew != 0;
836 :     }
837 :    
838 :     /**
839 :     * Removes from this Vector all of its elements that are contained in the
840 :     * specified Collection.
841 :     *
842 :     * @param c a collection of elements to be removed from the Vector
843 :     * @return true if this Vector changed as a result of the call
844 :     * @throws ClassCastException if the types of one or more elements
845 :     * in this vector are incompatible with the specified
846 :     * collection (optional)
847 :     * @throws NullPointerException if this vector contains one or more null
848 :     * elements and the specified collection does not support null
849 :     * elements (optional), or if the specified collection is null
850 :     * @since 1.2
851 :     */
852 :     public synchronized boolean removeAll(Collection<?> c) {
853 :     return super.removeAll(c);
854 :     }
855 :    
856 :     /**
857 :     * Retains only the elements in this Vector that are contained in the
858 :     * specified Collection. In other words, removes from this Vector all
859 :     * of its elements that are not contained in the specified Collection.
860 :     *
861 :     * @param c a collection of elements to be retained in this Vector
862 :     * (all other elements are removed)
863 :     * @return true if this Vector changed as a result of the call
864 :     * @throws ClassCastException if the types of one or more elements
865 :     * in this vector are incompatible with the specified
866 :     * collection (optional)
867 :     * @throws NullPointerException if this vector contains one or more null
868 :     * elements and the specified collection does not support null
869 :     * elements (optional), or if the specified collection is null
870 :     * @since 1.2
871 :     */
872 :     public synchronized boolean retainAll(Collection<?> c) {
873 :     return super.retainAll(c);
874 :     }
875 :    
876 :     /**
877 :     * Inserts all of the elements in the specified Collection into this
878 :     * Vector at the specified position. Shifts the element currently at
879 :     * that position (if any) and any subsequent elements to the right
880 :     * (increases their indices). The new elements will appear in the Vector
881 :     * in the order that they are returned by the specified Collection's
882 :     * iterator.
883 :     *
884 :     * @param index index at which to insert the first element from the
885 :     * specified collection
886 :     * @param c elements to be inserted into this Vector
887 : jsr166 1.14 * @return {@code true} if this Vector changed as a result of the call
888 : jsr166 1.18 * @throws ArrayIndexOutOfBoundsException if the index is out of range
889 :     * ({@code index < 0 || index > size()})
890 : dl 1.1 * @throws NullPointerException if the specified collection is null
891 :     * @since 1.2
892 :     */
893 :     public synchronized boolean addAll(int index, Collection<? extends E> c) {
894 :     modCount++;
895 :     if (index < 0 || index > elementCount)
896 :     throw new ArrayIndexOutOfBoundsException(index);
897 :    
898 :     Object[] a = c.toArray();
899 :     int numNew = a.length;
900 :     ensureCapacityHelper(elementCount + numNew);
901 :    
902 :     int numMoved = elementCount - index;
903 :     if (numMoved > 0)
904 :     System.arraycopy(elementData, index, elementData, index + numNew,
905 :     numMoved);
906 :    
907 :     System.arraycopy(a, 0, elementData, index, numNew);
908 :     elementCount += numNew;
909 :     return numNew != 0;
910 :     }
911 :    
912 :     /**
913 :     * Compares the specified Object with this Vector for equality. Returns
914 :     * true if and only if the specified Object is also a List, both Lists
915 :     * have the same size, and all corresponding pairs of elements in the two
916 : jsr166 1.14 * Lists are <em>equal</em>. (Two elements {@code e1} and
917 :     * {@code e2} are <em>equal</em> if {@code (e1==null ? e2==null :
918 :     * e1.equals(e2))}.) In other words, two Lists are defined to be
919 : dl 1.1 * equal if they contain the same elements in the same order.
920 :     *
921 :     * @param o the Object to be compared for equality with this Vector
922 :     * @return true if the specified Object is equal to this Vector
923 :     */
924 :     public synchronized boolean equals(Object o) {
925 :     return super.equals(o);
926 :     }
927 :    
928 :     /**
929 :     * Returns the hash code value for this Vector.
930 :     */
931 :     public synchronized int hashCode() {
932 :     return super.hashCode();
933 :     }
934 :    
935 :     /**
936 :     * Returns a string representation of this Vector, containing
937 :     * the String representation of each element.
938 :     */
939 :     public synchronized String toString() {
940 :     return super.toString();
941 :     }
942 :    
943 :     /**
944 :     * Removes from this List all of the elements whose index is between
945 :     * fromIndex, inclusive and toIndex, exclusive. Shifts any succeeding
946 :     * elements to the left (reduces their index).
947 : dl 1.10 * This call shortens the Vector by (toIndex - fromIndex) elements. (If
948 : dl 1.1 * toIndex==fromIndex, this operation has no effect.)
949 :     *
950 :     * @param fromIndex index of first element to be removed
951 :     * @param toIndex index after last element to be removed
952 :     */
953 :     protected synchronized void removeRange(int fromIndex, int toIndex) {
954 :     modCount++;
955 :     int numMoved = elementCount - toIndex;
956 :     System.arraycopy(elementData, toIndex, elementData, fromIndex,
957 :     numMoved);
958 :    
959 :     // Let gc do its work
960 :     int newElementCount = elementCount - (toIndex-fromIndex);
961 :     while (elementCount != newElementCount)
962 :     elementData[--elementCount] = null;
963 :     }
964 :    
965 :     /**
966 : jsr166 1.14 * Save the state of the {@code Vector} instance to a stream (that
967 : dl 1.1 * is, serialize it). This method is present merely for synchronization.
968 :     * It just calls the default writeObject method.
969 :     */
970 :     private synchronized void writeObject(java.io.ObjectOutputStream s)
971 :     throws java.io.IOException
972 :     {
973 :     s.defaultWriteObject();
974 :     }
975 :    
976 :     /**
977 :     * Returns a list-iterator of the elements in this list (in proper
978 :     * sequence), starting at the specified position in the list.
979 : dl 1.10 * Obeys the general contract of {@link List#listIterator(int)}.
980 : dl 1.1 *
981 : dl 1.10 * <p>The list-iterator is <i>fail-fast</i>: if the list is structurally
982 : dl 1.1 * modified at any time after the Iterator is created, in any way except
983 : dl 1.10 * through the list-iterator's own {@code remove} or {@code add}
984 : dl 1.1 * methods, the list-iterator will throw a
985 : dl 1.10 * {@code ConcurrentModificationException}. Thus, in the face of
986 : dl 1.1 * concurrent modification, the iterator fails quickly and cleanly, rather
987 :     * than risking arbitrary, non-deterministic behavior at an undetermined
988 :     * time in the future.
989 :     *
990 :     * @param index index of the first element to be returned from the
991 : dl 1.10 * list-iterator (by a call to {@link ListIterator#next})
992 :     * @return a list-iterator of the elements in this list (in proper
993 : dl 1.1 * sequence), starting at the specified position in the list
994 :     * @throws IndexOutOfBoundsException {@inheritDoc}
995 :     */
996 :     public synchronized ListIterator<E> listIterator(int index) {
997 :     if (index < 0 || index > elementCount)
998 :     throw new IndexOutOfBoundsException("Index: "+index);
999 : dl 1.10 return new VectorIterator(index, elementCount);
1000 : dl 1.1 }
1001 : jsr166 1.2
1002 : dl 1.1 /**
1003 : dl 1.3 * {@inheritDoc}
1004 :     */
1005 :     public synchronized ListIterator<E> listIterator() {
1006 : dl 1.10 return new VectorIterator(0, elementCount);
1007 : dl 1.3 }
1008 :    
1009 :     /**
1010 : dl 1.1 * Returns an iterator over the elements in this list in proper sequence.
1011 :     *
1012 :     * @return an iterator over the elements in this list in proper sequence
1013 :     */
1014 :     public synchronized Iterator<E> iterator() {
1015 : dl 1.10 return new VectorIterator(0, elementCount);
1016 : dl 1.1 }
1017 :    
1018 :     /**
1019 : dl 1.10 * Helper method to access array elements under synchronization by
1020 :     * iterators. The caller performs index check with respect to
1021 :     * expected bounds, so errors accessing the element are reported
1022 :     * as ConcurrentModificationExceptions.
1023 :     */
1024 :     final synchronized Object iteratorGet(int index, int expectedModCount) {
1025 :     if (modCount == expectedModCount) {
1026 :     try {
1027 :     return elementData[index];
1028 :     } catch(IndexOutOfBoundsException fallThrough) {
1029 :     }
1030 :     }
1031 :     throw new ConcurrentModificationException();
1032 :     }
1033 :    
1034 :     /**
1035 :     * Streamlined specialization of AbstractList version of iterator.
1036 : jsr166 1.19 * Locally performs bounds checks, but relies on outer Vector
1037 : dl 1.10 * to access elements under synchronization.
1038 : dl 1.1 */
1039 : dl 1.3 private final class VectorIterator implements ListIterator<E> {
1040 : dl 1.10 int cursor; // Index of next element to return;
1041 :     int fence; // Upper bound on cursor (cache of size())
1042 :     int lastRet; // Index of last element, or -1 if no such
1043 :     int expectedModCount; // To check for CME
1044 :    
1045 :     VectorIterator(int index, int fence) {
1046 :     this.cursor = index;
1047 :     this.fence = fence;
1048 :     this.lastRet = -1;
1049 :     this.expectedModCount = Vector.this.modCount;
1050 : dl 1.1 }
1051 :    
1052 :     public boolean hasNext() {
1053 : dl 1.10 return cursor < fence;
1054 : dl 1.1 }
1055 :    
1056 :     public boolean hasPrevious() {
1057 : dl 1.10 return cursor > 0;
1058 : dl 1.1 }
1059 :    
1060 :     public int nextIndex() {
1061 :     return cursor;
1062 :     }
1063 :    
1064 :     public int previousIndex() {
1065 :     return cursor - 1;
1066 :     }
1067 :    
1068 :     public E next() {
1069 : dl 1.10 int i = cursor;
1070 :     if (i >= fence)
1071 : dl 1.3 throw new NoSuchElementException();
1072 : dl 1.10 Object next = Vector.this.iteratorGet(i, expectedModCount);
1073 :     lastRet = i;
1074 :     cursor = i + 1;
1075 :     return (E)next;
1076 : dl 1.1 }
1077 : jsr166 1.4
1078 : dl 1.10 public E previous() {
1079 :     int i = cursor - 1;
1080 :     if (i < 0)
1081 : dl 1.3 throw new NoSuchElementException();
1082 : dl 1.10 Object prev = Vector.this.iteratorGet(i, expectedModCount);
1083 :     lastRet = i;
1084 :     cursor = i;
1085 :     return (E)prev;
1086 : dl 1.1 }
1087 :    
1088 : dl 1.10 public void set(E e) {
1089 :     if (lastRet < 0)
1090 : dl 1.1 throw new IllegalStateException();
1091 : dl 1.10 if (Vector.this.modCount != expectedModCount)
1092 :     throw new ConcurrentModificationException();
1093 :     try {
1094 :     Vector.this.set(lastRet, e);
1095 :     expectedModCount = Vector.this.modCount;
1096 : jsr166 1.4 } catch (IndexOutOfBoundsException ex) {
1097 : dl 1.3 throw new ConcurrentModificationException();
1098 :     }
1099 : dl 1.1 }
1100 :    
1101 : dl 1.10 public void remove() {
1102 :     int i = lastRet;
1103 :     if (i < 0)
1104 : dl 1.1 throw new IllegalStateException();
1105 : dl 1.10 if (Vector.this.modCount != expectedModCount)
1106 : dl 1.3 throw new ConcurrentModificationException();
1107 : dl 1.10 try {
1108 :     Vector.this.remove(i);
1109 :     if (i < cursor)
1110 :     cursor--;
1111 :     lastRet = -1;
1112 :     fence = Vector.this.size();
1113 :     expectedModCount = Vector.this.modCount;
1114 : dl 1.3 } catch (IndexOutOfBoundsException ex) {
1115 :     throw new ConcurrentModificationException();
1116 :     }
1117 : dl 1.1 }
1118 :    
1119 :     public void add(E e) {
1120 : dl 1.10 if (Vector.this.modCount != expectedModCount)
1121 : dl 1.3 throw new ConcurrentModificationException();
1122 :     try {
1123 :     int i = cursor;
1124 : dl 1.10 Vector.this.add(i, e);
1125 : dl 1.3 cursor = i + 1;
1126 : dl 1.10 lastRet = -1;
1127 :     fence = Vector.this.size();
1128 :     expectedModCount = Vector.this.modCount;
1129 : dl 1.3 } catch (IndexOutOfBoundsException ex) {
1130 :     throw new ConcurrentModificationException();
1131 :     }
1132 : dl 1.1 }
1133 :     }
1134 : dl 1.10
1135 :     /**
1136 :     * Returns a view of the portion of this List between fromIndex,
1137 :     * inclusive, and toIndex, exclusive. (If fromIndex and toIndex are
1138 :     * equal, the returned List is empty.) The returned List is backed by this
1139 :     * List, so changes in the returned List are reflected in this List, and
1140 :     * vice-versa. The returned List supports all of the optional List
1141 : jsr166 1.16 * operations supported by this List.
1142 : dl 1.10 *
1143 : jsr166 1.16 * <p>This method eliminates the need for explicit range operations (of
1144 : dl 1.10 * the sort that commonly exist for arrays). Any operation that expects
1145 :     * a List can be used as a range operation by operating on a subList view
1146 :     * instead of a whole List. For example, the following idiom
1147 :     * removes a range of elements from a List:
1148 :     * <pre>
1149 :     * list.subList(from, to).clear();
1150 :     * </pre>
1151 :     * Similar idioms may be constructed for indexOf and lastIndexOf,
1152 :     * and all of the algorithms in the Collections class can be applied to
1153 : jsr166 1.16 * a subList.
1154 : dl 1.10 *
1155 : jsr166 1.16 * <p>The semantics of the List returned by this method become undefined if
1156 : dl 1.10 * the backing list (i.e., this List) is <i>structurally modified</i> in
1157 :     * any way other than via the returned List. (Structural modifications are
1158 :     * those that change the size of the List, or otherwise perturb it in such
1159 :     * a fashion that iterations in progress may yield incorrect results.)
1160 :     *
1161 :     * @param fromIndex low endpoint (inclusive) of the subList
1162 :     * @param toIndex high endpoint (exclusive) of the subList
1163 :     * @return a view of the specified range within this List
1164 : jsr166 1.18 * @throws IndexOutOfBoundsException if an endpoint index value is out of range
1165 :     * {@code (fromIndex < 0 || toIndex > size)}
1166 :     * @throws IllegalArgumentException if the endpoint indices are out of order
1167 :     * {@code (fromIndex > toIndex)}
1168 : dl 1.10 */
1169 :     public synchronized List<E> subList(int fromIndex, int toIndex) {
1170 :     return new VectorSubList(this, this, fromIndex, fromIndex, toIndex);
1171 :     }
1172 :    
1173 :     /**
1174 :     * This class specializes the AbstractList version of SubList to
1175 :     * avoid the double-indirection penalty that would arise using a
1176 :     * synchronized wrapper, as well as to avoid some unnecessary
1177 :     * checks in sublist iterators.
1178 :     */
1179 :     private static final class VectorSubList<E> extends AbstractList<E> implements RandomAccess {
1180 :     final Vector<E> base; // base list
1181 :     final AbstractList<E> parent; // Creating list
1182 :     final int baseOffset; // index wrt Vector
1183 :     final int parentOffset; // index wrt parent
1184 :     int length; // length of sublist
1185 :    
1186 : jsr166 1.11 VectorSubList(Vector<E> base, AbstractList<E> parent, int baseOffset,
1187 : dl 1.10 int fromIndex, int toIndex) {
1188 :     if (fromIndex < 0)
1189 :     throw new IndexOutOfBoundsException("fromIndex = " + fromIndex);
1190 :     if (toIndex > parent.size())
1191 :     throw new IndexOutOfBoundsException("toIndex = " + toIndex);
1192 :     if (fromIndex > toIndex)
1193 :     throw new IllegalArgumentException("fromIndex(" + fromIndex +
1194 :     ") > toIndex(" + toIndex + ")");
1195 :    
1196 :     this.base = base;
1197 :     this.parent = parent;
1198 :     this.baseOffset = baseOffset;
1199 :     this.parentOffset = fromIndex;
1200 :     this.length = toIndex - fromIndex;
1201 :     modCount = base.modCount;
1202 :     }
1203 :    
1204 :     /**
1205 :     * Returns an IndexOutOfBoundsException with nicer message
1206 :     */
1207 :     private IndexOutOfBoundsException indexError(int index) {
1208 : jsr166 1.11 return new IndexOutOfBoundsException("Index: " + index +
1209 : dl 1.10 ", Size: " + length);
1210 :     }
1211 :    
1212 :     public E set(int index, E element) {
1213 :     synchronized(base) {
1214 :     if (index < 0 || index >= length)
1215 :     throw indexError(index);
1216 :     if (base.modCount != modCount)
1217 :     throw new ConcurrentModificationException();
1218 :     return base.set(index + baseOffset, element);
1219 :     }
1220 :     }
1221 :    
1222 :     public E get(int index) {
1223 :     synchronized(base) {
1224 :     if (index < 0 || index >= length)
1225 :     throw indexError(index);
1226 :     if (base.modCount != modCount)
1227 :     throw new ConcurrentModificationException();
1228 :     return base.get(index + baseOffset);
1229 :     }
1230 :     }
1231 :    
1232 :     public int size() {
1233 :     synchronized(base) {
1234 :     if (base.modCount != modCount)
1235 :     throw new ConcurrentModificationException();
1236 :     return length;
1237 :     }
1238 :     }
1239 :    
1240 :     public void add(int index, E element) {
1241 :     synchronized(base) {
1242 :     if (index < 0 || index > length)
1243 :     throw indexError(index);
1244 :     if (base.modCount != modCount)
1245 :     throw new ConcurrentModificationException();
1246 :     parent.add(index + parentOffset, element);
1247 :     length++;
1248 :     modCount = base.modCount;
1249 :     }
1250 :     }
1251 :    
1252 :     public E remove(int index) {
1253 :     synchronized(base) {
1254 :     if (index < 0 || index >= length)
1255 :     throw indexError(index);
1256 :     if (base.modCount != modCount)
1257 :     throw new ConcurrentModificationException();
1258 :     E result = parent.remove(index + parentOffset);
1259 :     length--;
1260 :     modCount = base.modCount;
1261 :     return result;
1262 :     }
1263 :     }
1264 :    
1265 :     protected void removeRange(int fromIndex, int toIndex) {
1266 :     synchronized(base) {
1267 :     if (base.modCount != modCount)
1268 :     throw new ConcurrentModificationException();
1269 : jsr166 1.11 parent.removeRange(fromIndex + parentOffset,
1270 : dl 1.10 toIndex + parentOffset);
1271 :     length -= (toIndex-fromIndex);
1272 :     modCount = base.modCount;
1273 :     }
1274 :     }
1275 :    
1276 :     public boolean addAll(Collection<? extends E> c) {
1277 :     return addAll(length, c);
1278 :     }
1279 :    
1280 :     public boolean addAll(int index, Collection<? extends E> c) {
1281 :     synchronized(base) {
1282 :     if (index < 0 || index > length)
1283 :     throw indexError(index);
1284 :     int cSize = c.size();
1285 :     if (cSize==0)
1286 :     return false;
1287 : jsr166 1.11
1288 : dl 1.10 if (base.modCount != modCount)
1289 :     throw new ConcurrentModificationException();
1290 :     parent.addAll(parentOffset + index, c);
1291 :     modCount = base.modCount;
1292 :     length += cSize;
1293 :     return true;
1294 :     }
1295 :     }
1296 :    
1297 :     public boolean equals(Object o) {
1298 :     synchronized(base) {return super.equals(o);}
1299 :     }
1300 :    
1301 :     public int hashCode() {
1302 :     synchronized(base) {return super.hashCode();}
1303 :     }
1304 :    
1305 :     public int indexOf(Object o) {
1306 :     synchronized(base) {return super.indexOf(o);}
1307 :     }
1308 :    
1309 :     public int lastIndexOf(Object o) {
1310 :     synchronized(base) {return super.lastIndexOf(o);}
1311 :     }
1312 :    
1313 :     public List<E> subList(int fromIndex, int toIndex) {
1314 : jsr166 1.11 return new VectorSubList(base, this, fromIndex + baseOffset,
1315 : dl 1.10 fromIndex, toIndex);
1316 :     }
1317 :    
1318 :     public Iterator<E> iterator() {
1319 :     synchronized(base) {
1320 :     return new VectorSubListIterator(this, 0);
1321 :     }
1322 :     }
1323 : jsr166 1.11
1324 : dl 1.10 public synchronized ListIterator<E> listIterator() {
1325 :     synchronized(base) {
1326 :     return new VectorSubListIterator(this, 0);
1327 :     }
1328 :     }
1329 :    
1330 :     public ListIterator<E> listIterator(int index) {
1331 :     synchronized(base) {
1332 :     if (index < 0 || index > length)
1333 :     throw indexError(index);
1334 :     return new VectorSubListIterator(this, index);
1335 :     }
1336 :     }
1337 :    
1338 :     /**
1339 :     * Same idea as VectorIterator, except routing structural
1340 :     * change operations through the sublist.
1341 :     */
1342 :     private static final class VectorSubListIterator<E> implements ListIterator<E> {
1343 :     final Vector<E> base; // base list
1344 :     final VectorSubList<E> outer; // Sublist creating this iteraor
1345 :     final int offset; // cursor offset wrt base
1346 :     int cursor; // Current index
1347 :     int fence; // Upper bound on cursor
1348 :     int lastRet; // Index of returned element, or -1
1349 :     int expectedModCount; // Expected modCount of base Vector
1350 : jsr166 1.11
1351 : dl 1.10 VectorSubListIterator(VectorSubList<E> list, int index) {
1352 :     this.lastRet = -1;
1353 :     this.cursor = index;
1354 :     this.outer = list;
1355 :     this.offset = list.baseOffset;
1356 :     this.fence = list.length;
1357 :     this.base = list.base;
1358 :     this.expectedModCount = base.modCount;
1359 :     }
1360 : jsr166 1.11
1361 : dl 1.10 public boolean hasNext() {
1362 :     return cursor < fence;
1363 :     }
1364 : jsr166 1.11
1365 : dl 1.10 public boolean hasPrevious() {
1366 :     return cursor > 0;
1367 :     }
1368 : jsr166 1.11
1369 : dl 1.10 public int nextIndex() {
1370 :     return cursor;
1371 :     }
1372 : jsr166 1.11
1373 : dl 1.10 public int previousIndex() {
1374 :     return cursor - 1;
1375 :     }
1376 : jsr166 1.11
1377 : dl 1.10 public E next() {
1378 :     int i = cursor;
1379 :     if (cursor >= fence)
1380 :     throw new NoSuchElementException();
1381 :     Object next = base.iteratorGet(i + offset, expectedModCount);
1382 :     lastRet = i;
1383 :     cursor = i + 1;
1384 :     return (E)next;
1385 :     }
1386 : jsr166 1.11
1387 : dl 1.10 public E previous() {
1388 :     int i = cursor - 1;
1389 :     if (i < 0)
1390 :     throw new NoSuchElementException();
1391 :     Object prev = base.iteratorGet(i + offset, expectedModCount);
1392 :     lastRet = i;
1393 :     cursor = i;
1394 :     return (E)prev;
1395 :     }
1396 : jsr166 1.11
1397 : dl 1.10 public void set(E e) {
1398 :     if (lastRet < 0)
1399 :     throw new IllegalStateException();
1400 :     if (base.modCount != expectedModCount)
1401 :     throw new ConcurrentModificationException();
1402 :     try {
1403 :     outer.set(lastRet, e);
1404 :     expectedModCount = base.modCount;
1405 :     } catch (IndexOutOfBoundsException ex) {
1406 :     throw new ConcurrentModificationException();
1407 :     }
1408 :     }
1409 : jsr166 1.11
1410 : dl 1.10 public void remove() {
1411 :     int i = lastRet;
1412 :     if (i < 0)
1413 :     throw new IllegalStateException();
1414 :     if (base.modCount != expectedModCount)
1415 :     throw new ConcurrentModificationException();
1416 :     try {
1417 :     outer.remove(i);
1418 :     if (i < cursor)
1419 :     cursor--;
1420 :     lastRet = -1;
1421 :     fence = outer.length;
1422 :     expectedModCount = base.modCount;
1423 :     } catch (IndexOutOfBoundsException ex) {
1424 :     throw new ConcurrentModificationException();
1425 :     }
1426 :     }
1427 : jsr166 1.11
1428 : dl 1.10 public void add(E e) {
1429 :     if (base.modCount != expectedModCount)
1430 :     throw new ConcurrentModificationException();
1431 :     try {
1432 :     int i = cursor;
1433 :     outer.add(i, e);
1434 :     cursor = i + 1;
1435 :     lastRet = -1;
1436 :     fence = outer.length;
1437 :     expectedModCount = base.modCount;
1438 :     } catch (IndexOutOfBoundsException ex) {
1439 :     throw new ConcurrentModificationException();
1440 :     }
1441 :     }
1442 :     }
1443 :     }
1444 : dl 1.1 }
1445 : dl 1.10
1446 :    
1447 : jsr166 1.11

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