1 /* 2 * Copyright (c) 1994, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.util; 27 28 import java.io.IOException; 29 import java.io.ObjectInputStream; 30 import java.io.StreamCorruptedException; 31 import java.util.function.Consumer; 32 import java.util.function.Predicate; 33 import java.util.function.UnaryOperator; 34 35 /** 36 * The {@code Vector} class implements a growable array of 37 * objects. Like an array, it contains components that can be 38 * accessed using an integer index. However, the size of a 39 * {@code Vector} can grow or shrink as needed to accommodate 40 * adding and removing items after the {@code Vector} has been created. 41 * 42 * <p>Each vector tries to optimize storage management by maintaining a 43 * {@code capacity} and a {@code capacityIncrement}. The 44 * {@code capacity} is always at least as large as the vector 45 * size; it is usually larger because as components are added to the 46 * vector, the vector's storage increases in chunks the size of 47 * {@code capacityIncrement}. An application can increase the 48 * capacity of a vector before inserting a large number of 49 * components; this reduces the amount of incremental reallocation. 50 * 51 * <p><a name="fail-fast"> 52 * The iterators returned by this class's {@link #iterator() iterator} and 53 * {@link #listIterator(int) listIterator} methods are <em>fail-fast</em></a>: 54 * if the vector is structurally modified at any time after the iterator is 55 * created, in any way except through the iterator's own 56 * {@link ListIterator#remove() remove} or 57 * {@link ListIterator#add(Object) add} methods, the iterator will throw a 58 * {@link ConcurrentModificationException}. Thus, in the face of 59 * concurrent modification, the iterator fails quickly and cleanly, rather 60 * than risking arbitrary, non-deterministic behavior at an undetermined 61 * time in the future. The {@link Enumeration Enumerations} returned by 62 * the {@link #elements() elements} method are <em>not</em> fail-fast. 63 * 64 * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed 65 * as it is, generally speaking, impossible to make any hard guarantees in the 66 * presence of unsynchronized concurrent modification. Fail-fast iterators 67 * throw {@code ConcurrentModificationException} on a best-effort basis. 68 * Therefore, it would be wrong to write a program that depended on this 69 * exception for its correctness: <i>the fail-fast behavior of iterators 70 * should be used only to detect bugs.</i> 71 * 72 * <p>As of the Java 2 platform v1.2, this class was retrofitted to 73 * implement the {@link List} interface, making it a member of the 74 * <a href="{@docRoot}/../technotes/guides/collections/index.html"> 75 * Java Collections Framework</a>. Unlike the new collection 76 * implementations, {@code Vector} is synchronized. If a thread-safe 77 * implementation is not needed, it is recommended to use {@link 78 * ArrayList} in place of {@code Vector}. 79 * 80 * @author Lee Boynton 81 * @author Jonathan Payne 82 * @see Collection 83 * @see LinkedList 84 * @since JDK1.0 85 */ 86 public class Vector<E> 87 extends AbstractList<E> 88 implements List<E>, RandomAccess, Cloneable, java.io.Serializable 89 { 90 /** 91 * The array buffer into which the components of the vector are 92 * stored. The capacity of the vector is the length of this array buffer, 93 * and is at least large enough to contain all the vector's elements. 94 * 95 * <p>Any array elements following the last element in the Vector are null. 96 * 97 * @serial 98 */ 99 protected Object[] elementData; 100 101 /** 102 * The number of valid components in this {@code Vector} object. 103 * Components {@code elementData[0]} through 104 * {@code elementData[elementCount-1]} are the actual items. 105 * 106 * @serial 107 */ 108 protected int elementCount; 109 110 /** 111 * The amount by which the capacity of the vector is automatically 112 * incremented when its size becomes greater than its capacity. If 113 * the capacity increment is less than or equal to zero, the capacity 114 * of the vector is doubled each time it needs to grow. 115 * 116 * @serial 117 */ 118 protected int capacityIncrement; 119 120 /** use serialVersionUID from JDK 1.0.2 for interoperability */ 121 private static final long serialVersionUID = -2767605614048989439L; 122 123 /** 124 * Constructs an empty vector with the specified initial capacity and 125 * capacity increment. 126 * 127 * @param initialCapacity the initial capacity of the vector 128 * @param capacityIncrement the amount by which the capacity is 129 * increased when the vector overflows 130 * @throws IllegalArgumentException if the specified initial capacity 131 * is negative 132 */ Vector(int initialCapacity, int capacityIncrement)133 public Vector(int initialCapacity, int capacityIncrement) { 134 super(); 135 if (initialCapacity < 0) 136 throw new IllegalArgumentException("Illegal Capacity: "+ 137 initialCapacity); 138 this.elementData = new Object[initialCapacity]; 139 this.capacityIncrement = capacityIncrement; 140 } 141 142 /** 143 * Constructs an empty vector with the specified initial capacity and 144 * with its capacity increment equal to zero. 145 * 146 * @param initialCapacity the initial capacity of the vector 147 * @throws IllegalArgumentException if the specified initial capacity 148 * is negative 149 */ Vector(int initialCapacity)150 public Vector(int initialCapacity) { 151 this(initialCapacity, 0); 152 } 153 154 /** 155 * Constructs an empty vector so that its internal data array 156 * has size {@code 10} and its standard capacity increment is 157 * zero. 158 */ Vector()159 public Vector() { 160 this(10); 161 } 162 163 /** 164 * Constructs a vector containing the elements of the specified 165 * collection, in the order they are returned by the collection's 166 * iterator. 167 * 168 * @param c the collection whose elements are to be placed into this 169 * vector 170 * @throws NullPointerException if the specified collection is null 171 * @since 1.2 172 */ Vector(Collection<? extends E> c)173 public Vector(Collection<? extends E> c) { 174 Object[] a = c.toArray(); 175 elementCount = a.length; 176 if (c.getClass() == ArrayList.class) { 177 elementData = a; 178 } else { 179 elementData = Arrays.copyOf(a, elementCount, Object[].class); 180 } 181 } 182 183 /** 184 * Copies the components of this vector into the specified array. 185 * The item at index {@code k} in this vector is copied into 186 * component {@code k} of {@code anArray}. 187 * 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 */ copyInto(Object[] anArray)196 public synchronized void copyInto(Object[] anArray) { 197 System.arraycopy(elementData, 0, anArray, 0, elementCount); 198 } 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 * its internal data array, kept in the field {@code elementData}, 205 * with a smaller one. An application can use this operation to 206 * minimize the storage of a vector. 207 */ trimToSize()208 public synchronized void trimToSize() { 209 modCount++; 210 int oldCapacity = elementData.length; 211 if (elementCount < oldCapacity) { 212 elementData = Arrays.copyOf(elementData, elementCount); 213 } 214 } 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 * {@code minCapacity}, then its capacity is increased by replacing its 223 * internal data array, kept in the field {@code elementData}, with a 224 * larger one. The size of the new data array will be the old size plus 225 * {@code capacityIncrement}, unless the value of 226 * {@code capacityIncrement} is less than or equal to zero, in which case 227 * the new capacity will be twice the old capacity; but if this new size 228 * is still smaller than {@code minCapacity}, then the new capacity will 229 * be {@code minCapacity}. 230 * 231 * @param minCapacity the desired minimum capacity 232 */ ensureCapacity(int minCapacity)233 public synchronized void ensureCapacity(int minCapacity) { 234 if (minCapacity > 0) { 235 modCount++; 236 ensureCapacityHelper(minCapacity); 237 } 238 } 239 240 /** 241 * This implements the unsynchronized semantics of ensureCapacity. 242 * Synchronized methods in this class can internally call this 243 * method for ensuring capacity without incurring the cost of an 244 * extra synchronization. 245 * 246 * @see #ensureCapacity(int) 247 */ ensureCapacityHelper(int minCapacity)248 private void ensureCapacityHelper(int minCapacity) { 249 // overflow-conscious code 250 if (minCapacity - elementData.length > 0) 251 grow(minCapacity); 252 } 253 254 /** 255 * The maximum size of array to allocate. 256 * Some VMs reserve some header words in an array. 257 * Attempts to allocate larger arrays may result in 258 * OutOfMemoryError: Requested array size exceeds VM limit 259 */ 260 private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; 261 grow(int minCapacity)262 private void grow(int minCapacity) { 263 // overflow-conscious code 264 int oldCapacity = elementData.length; 265 int newCapacity = oldCapacity + ((capacityIncrement > 0) ? 266 capacityIncrement : oldCapacity); 267 if (newCapacity - minCapacity < 0) 268 newCapacity = minCapacity; 269 if (newCapacity - MAX_ARRAY_SIZE > 0) 270 newCapacity = hugeCapacity(minCapacity); 271 elementData = Arrays.copyOf(elementData, newCapacity); 272 } 273 hugeCapacity(int minCapacity)274 private static int hugeCapacity(int minCapacity) { 275 if (minCapacity < 0) // overflow 276 throw new OutOfMemoryError(); 277 return (minCapacity > MAX_ARRAY_SIZE) ? 278 Integer.MAX_VALUE : 279 MAX_ARRAY_SIZE; 280 } 281 282 /** 283 * Sets the size of this vector. If the new size is greater than the 284 * current size, new {@code null} items are added to the end of 285 * the vector. If the new size is less than the current size, all 286 * components at index {@code newSize} and greater are discarded. 287 * 288 * @param newSize the new size of this vector 289 * @throws ArrayIndexOutOfBoundsException if the new size is negative 290 */ setSize(int newSize)291 public synchronized void setSize(int newSize) { 292 modCount++; 293 if (newSize > elementCount) { 294 ensureCapacityHelper(newSize); 295 } else { 296 for (int i = newSize ; i < elementCount ; i++) { 297 elementData[i] = null; 298 } 299 } 300 elementCount = newSize; 301 } 302 303 /** 304 * Returns the current capacity of this vector. 305 * 306 * @return the current capacity (the length of its internal 307 * data array, kept in the field {@code elementData} 308 * of this vector) 309 */ capacity()310 public synchronized int capacity() { 311 return elementData.length; 312 } 313 314 /** 315 * Returns the number of components in this vector. 316 * 317 * @return the number of components in this vector 318 */ size()319 public synchronized int size() { 320 return elementCount; 321 } 322 323 /** 324 * Tests if this vector has no components. 325 * 326 * @return {@code true} if and only if this vector has 327 * no components, that is, its size is zero; 328 * {@code false} otherwise. 329 */ isEmpty()330 public synchronized boolean isEmpty() { 331 return elementCount == 0; 332 } 333 334 /** 335 * Returns an enumeration of the components of this vector. The 336 * returned {@code Enumeration} object will generate all items in 337 * this vector. The first item generated is the item at index {@code 0}, 338 * then the item at index {@code 1}, and so on. 339 * 340 * @return an enumeration of the components of this vector 341 * @see Iterator 342 */ elements()343 public Enumeration<E> elements() { 344 return new Enumeration<E>() { 345 int count = 0; 346 347 public boolean hasMoreElements() { 348 return count < elementCount; 349 } 350 351 public E nextElement() { 352 synchronized (Vector.this) { 353 if (count < elementCount) { 354 return elementData(count++); 355 } 356 } 357 throw new NoSuchElementException("Vector Enumeration"); 358 } 359 }; 360 } 361 362 /** 363 * Returns {@code true} if this vector contains the specified element. 364 * More formally, returns {@code true} if and only if this vector 365 * contains at least one element {@code e} such that 366 * <tt>(o==null ? e==null : o.equals(e))</tt>. 367 * 368 * @param o element whose presence in this vector is to be tested 369 * @return {@code true} if this vector contains the specified element 370 */ contains(Object o)371 public boolean contains(Object o) { 372 return indexOf(o, 0) >= 0; 373 } 374 375 /** 376 * Returns the index of the first occurrence of the specified element 377 * in this vector, or -1 if this vector does not contain the element. 378 * More formally, returns the lowest index {@code i} such that 379 * <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, 380 * or -1 if there is no such index. 381 * 382 * @param o element to search for 383 * @return the index of the first occurrence of the specified element in 384 * this vector, or -1 if this vector does not contain the element 385 */ indexOf(Object o)386 public int indexOf(Object o) { 387 return indexOf(o, 0); 388 } 389 390 /** 391 * Returns the index of the first occurrence of the specified element in 392 * this vector, searching forwards from {@code index}, or returns -1 if 393 * the element is not found. 394 * More formally, returns the lowest index {@code i} such that 395 * <tt>(i >= index && (o==null ? get(i)==null : o.equals(get(i))))</tt>, 396 * or -1 if there is no such index. 397 * 398 * @param o element to search for 399 * @param index index to start searching from 400 * @return the index of the first occurrence of the element in 401 * this vector at position {@code index} or later in the vector; 402 * {@code -1} if the element is not found. 403 * @throws IndexOutOfBoundsException if the specified index is negative 404 * @see Object#equals(Object) 405 */ indexOf(Object o, int index)406 public synchronized int indexOf(Object o, int index) { 407 if (o == null) { 408 for (int i = index ; i < elementCount ; i++) 409 if (elementData[i]==null) 410 return i; 411 } else { 412 for (int i = index ; i < elementCount ; i++) 413 if (o.equals(elementData[i])) 414 return i; 415 } 416 return -1; 417 } 418 419 /** 420 * Returns the index of the last occurrence of the specified element 421 * in this vector, or -1 if this vector does not contain the element. 422 * More formally, returns the highest index {@code i} such that 423 * <tt>(o==null ? get(i)==null : o.equals(get(i)))</tt>, 424 * or -1 if there is no such index. 425 * 426 * @param o element to search for 427 * @return the index of the last occurrence of the specified element in 428 * this vector, or -1 if this vector does not contain the element 429 */ lastIndexOf(Object o)430 public synchronized int lastIndexOf(Object o) { 431 return lastIndexOf(o, elementCount-1); 432 } 433 434 /** 435 * Returns the index of the last occurrence of the specified element in 436 * this vector, searching backwards from {@code index}, or returns -1 if 437 * the element is not found. 438 * More formally, returns the highest index {@code i} such that 439 * <tt>(i <= index && (o==null ? get(i)==null : o.equals(get(i))))</tt>, 440 * or -1 if there is no such index. 441 * 442 * @param o element to search for 443 * @param index index to start searching backwards from 444 * @return the index of the last occurrence of the element at position 445 * less than or equal to {@code index} in this vector; 446 * -1 if the element is not found. 447 * @throws IndexOutOfBoundsException if the specified index is greater 448 * than or equal to the current size of this vector 449 */ lastIndexOf(Object o, int index)450 public synchronized int lastIndexOf(Object o, int index) { 451 if (index >= elementCount) 452 throw new IndexOutOfBoundsException(index + " >= "+ elementCount); 453 454 if (o == null) { 455 for (int i = index; i >= 0; i--) 456 if (elementData[i]==null) 457 return i; 458 } else { 459 for (int i = index; i >= 0; i--) 460 if (o.equals(elementData[i])) 461 return i; 462 } 463 return -1; 464 } 465 466 /** 467 * Returns the component at the specified index. 468 * 469 * <p>This method is identical in functionality to the {@link #get(int)} 470 * method (which is part of the {@link List} interface). 471 * 472 * @param index an index into this vector 473 * @return the component at the specified index 474 * @throws ArrayIndexOutOfBoundsException if the index is out of range 475 * ({@code index < 0 || index >= size()}) 476 */ elementAt(int index)477 public synchronized E elementAt(int index) { 478 if (index >= elementCount) { 479 throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount); 480 } 481 482 return elementData(index); 483 } 484 485 /** 486 * Returns the first component (the item at index {@code 0}) of 487 * this vector. 488 * 489 * @return the first component of this vector 490 * @throws NoSuchElementException if this vector has no components 491 */ firstElement()492 public synchronized E firstElement() { 493 if (elementCount == 0) { 494 throw new NoSuchElementException(); 495 } 496 return elementData(0); 497 } 498 499 /** 500 * Returns the last component of the vector. 501 * 502 * @return the last component of the vector, i.e., the component at index 503 * <code>size() - 1</code>. 504 * @throws NoSuchElementException if this vector is empty 505 */ lastElement()506 public synchronized E lastElement() { 507 if (elementCount == 0) { 508 throw new NoSuchElementException(); 509 } 510 return elementData(elementCount - 1); 511 } 512 513 /** 514 * Sets the component at the specified {@code index} of this 515 * vector to be the specified object. The previous component at that 516 * position is discarded. 517 * 518 * <p>The index must be a value greater than or equal to {@code 0} 519 * and less than the current size of the vector. 520 * 521 * <p>This method is identical in functionality to the 522 * {@link #set(int, Object) set(int, E)} 523 * method (which is part of the {@link List} interface). Note that the 524 * {@code set} method reverses the order of the parameters, to more closely 525 * match array usage. Note also that the {@code set} method returns the 526 * old value that was stored at the specified position. 527 * 528 * @param obj what the component is to be set to 529 * @param index the specified index 530 * @throws ArrayIndexOutOfBoundsException if the index is out of range 531 * ({@code index < 0 || index >= size()}) 532 */ setElementAt(E obj, int index)533 public synchronized void setElementAt(E obj, int index) { 534 if (index >= elementCount) { 535 throw new ArrayIndexOutOfBoundsException(index + " >= " + 536 elementCount); 537 } 538 elementData[index] = obj; 539 } 540 541 /** 542 * Deletes the component at the specified index. Each component in 543 * this vector with an index greater or equal to the specified 544 * {@code index} is shifted downward to have an index one 545 * smaller than the value it had previously. The size of this vector 546 * is decreased by {@code 1}. 547 * 548 * <p>The index must be a value greater than or equal to {@code 0} 549 * and less than the current size of the vector. 550 * 551 * <p>This method is identical in functionality to the {@link #remove(int)} 552 * method (which is part of the {@link List} interface). Note that the 553 * {@code remove} method returns the old value that was stored at the 554 * specified position. 555 * 556 * @param index the index of the object to remove 557 * @throws ArrayIndexOutOfBoundsException if the index is out of range 558 * ({@code index < 0 || index >= size()}) 559 */ removeElementAt(int index)560 public synchronized void removeElementAt(int index) { 561 modCount++; 562 if (index >= elementCount) { 563 throw new ArrayIndexOutOfBoundsException(index + " >= " + 564 elementCount); 565 } 566 else if (index < 0) { 567 throw new ArrayIndexOutOfBoundsException(index); 568 } 569 int j = elementCount - index - 1; 570 if (j > 0) { 571 System.arraycopy(elementData, index + 1, elementData, index, j); 572 } 573 elementCount--; 574 elementData[elementCount] = null; /* to let gc do its work */ 575 } 576 577 /** 578 * Inserts the specified object as a component in this vector at the 579 * specified {@code index}. Each component in this vector with 580 * an index greater or equal to the specified {@code index} is 581 * shifted upward to have an index one greater than the value it had 582 * previously. 583 * 584 * <p>The index must be a value greater than or equal to {@code 0} 585 * and less than or equal to the current size of the vector. (If the 586 * index is equal to the current size of the vector, the new element 587 * is appended to the Vector.) 588 * 589 * <p>This method is identical in functionality to the 590 * {@link #add(int, Object) add(int, E)} 591 * method (which is part of the {@link List} interface). Note that the 592 * {@code add} method reverses the order of the parameters, to more closely 593 * match array usage. 594 * 595 * @param obj the component to insert 596 * @param index where to insert the new component 597 * @throws ArrayIndexOutOfBoundsException if the index is out of range 598 * ({@code index < 0 || index > size()}) 599 */ insertElementAt(E obj, int index)600 public synchronized void insertElementAt(E obj, int index) { 601 modCount++; 602 if (index > elementCount) { 603 throw new ArrayIndexOutOfBoundsException(index 604 + " > " + elementCount); 605 } 606 ensureCapacityHelper(elementCount + 1); 607 System.arraycopy(elementData, index, elementData, index + 1, elementCount - index); 608 elementData[index] = obj; 609 elementCount++; 610 } 611 612 /** 613 * Adds the specified component to the end of this vector, 614 * increasing its size by one. The capacity of this vector is 615 * increased if its size becomes greater than its capacity. 616 * 617 * <p>This method is identical in functionality to the 618 * {@link #add(Object) add(E)} 619 * method (which is part of the {@link List} interface). 620 * 621 * @param obj the component to be added 622 */ addElement(E obj)623 public synchronized void addElement(E obj) { 624 modCount++; 625 ensureCapacityHelper(elementCount + 1); 626 elementData[elementCount++] = obj; 627 } 628 629 /** 630 * Removes the first (lowest-indexed) occurrence of the argument 631 * from this vector. If the object is found in this vector, each 632 * component in the vector with an index greater or equal to the 633 * object's index is shifted downward to have an index one smaller 634 * than the value it had previously. 635 * 636 * <p>This method is identical in functionality to the 637 * {@link #remove(Object)} method (which is part of the 638 * {@link List} interface). 639 * 640 * @param obj the component to be removed 641 * @return {@code true} if the argument was a component of this 642 * vector; {@code false} otherwise. 643 */ removeElement(Object obj)644 public synchronized boolean removeElement(Object obj) { 645 modCount++; 646 int i = indexOf(obj); 647 if (i >= 0) { 648 removeElementAt(i); 649 return true; 650 } 651 return false; 652 } 653 654 /** 655 * Removes all components from this vector and sets its size to zero. 656 * 657 * <p>This method is identical in functionality to the {@link #clear} 658 * method (which is part of the {@link List} interface). 659 */ removeAllElements()660 public synchronized void removeAllElements() { 661 modCount++; 662 // Let gc do its work 663 for (int i = 0; i < elementCount; i++) 664 elementData[i] = null; 665 666 elementCount = 0; 667 } 668 669 /** 670 * Returns a clone of this vector. The copy will contain a 671 * reference to a clone of the internal data array, not a reference 672 * to the original internal data array of this {@code Vector} object. 673 * 674 * @return a clone of this vector 675 */ clone()676 public synchronized Object clone() { 677 try { 678 @SuppressWarnings("unchecked") 679 Vector<E> v = (Vector<E>) super.clone(); 680 v.elementData = Arrays.copyOf(elementData, elementCount); 681 v.modCount = 0; 682 return v; 683 } catch (CloneNotSupportedException e) { 684 // this shouldn't happen, since we are Cloneable 685 throw new InternalError(e); 686 } 687 } 688 689 /** 690 * Returns an array containing all of the elements in this Vector 691 * in the correct order. 692 * 693 * @since 1.2 694 */ toArray()695 public synchronized Object[] toArray() { 696 return Arrays.copyOf(elementData, elementCount); 697 } 698 699 /** 700 * Returns an array containing all of the elements in this Vector in the 701 * correct order; the runtime type of the returned array is that of the 702 * specified array. If the Vector fits in the specified array, it is 703 * returned therein. Otherwise, a new array is allocated with the runtime 704 * type of the specified array and the size of this Vector. 705 * 706 * <p>If the Vector fits in the specified array with room to spare 707 * (i.e., the array has more elements than the Vector), 708 * the element in the array immediately following the end of the 709 * Vector is set to null. (This is useful in determining the length 710 * of the Vector <em>only</em> if the caller knows that the Vector 711 * does not contain any null elements.) 712 * 713 * @param a the array into which the elements of the Vector are to 714 * be stored, if it is big enough; otherwise, a new array of the 715 * same runtime type is allocated for this purpose. 716 * @return an array containing the elements of the Vector 717 * @throws ArrayStoreException if the runtime type of a is not a supertype 718 * of the runtime type of every element in this Vector 719 * @throws NullPointerException if the given array is null 720 * @since 1.2 721 */ 722 @SuppressWarnings("unchecked") toArray(T[] a)723 public synchronized <T> T[] toArray(T[] a) { 724 if (a.length < elementCount) 725 return (T[]) Arrays.copyOf(elementData, elementCount, a.getClass()); 726 727 System.arraycopy(elementData, 0, a, 0, elementCount); 728 729 if (a.length > elementCount) 730 a[elementCount] = null; 731 732 return a; 733 } 734 735 // Positional Access Operations 736 737 @SuppressWarnings("unchecked") elementData(int index)738 E elementData(int index) { 739 return (E) elementData[index]; 740 } 741 742 /** 743 * Returns the element at the specified position in this Vector. 744 * 745 * @param index index of the element to return 746 * @return object at the specified index 747 * @throws ArrayIndexOutOfBoundsException if the index is out of range 748 * ({@code index < 0 || index >= size()}) 749 * @since 1.2 750 */ get(int index)751 public synchronized E get(int index) { 752 if (index >= elementCount) 753 throw new ArrayIndexOutOfBoundsException(index); 754 755 return elementData(index); 756 } 757 758 /** 759 * Replaces the element at the specified position in this Vector with the 760 * specified element. 761 * 762 * @param index index of the element to replace 763 * @param element element to be stored at the specified position 764 * @return the element previously at the specified position 765 * @throws ArrayIndexOutOfBoundsException if the index is out of range 766 * ({@code index < 0 || index >= size()}) 767 * @since 1.2 768 */ set(int index, E element)769 public synchronized E set(int index, E element) { 770 if (index >= elementCount) 771 throw new ArrayIndexOutOfBoundsException(index); 772 773 E oldValue = elementData(index); 774 elementData[index] = element; 775 return oldValue; 776 } 777 778 /** 779 * Appends the specified element to the end of this Vector. 780 * 781 * @param e element to be appended to this Vector 782 * @return {@code true} (as specified by {@link Collection#add}) 783 * @since 1.2 784 */ add(E e)785 public synchronized boolean add(E e) { 786 modCount++; 787 ensureCapacityHelper(elementCount + 1); 788 elementData[elementCount++] = e; 789 return true; 790 } 791 792 /** 793 * Removes the first occurrence of the specified element in this Vector 794 * If the Vector does not contain the element, it is unchanged. More 795 * formally, removes the element with the lowest index i such that 796 * {@code (o==null ? get(i)==null : o.equals(get(i)))} (if such 797 * an element exists). 798 * 799 * @param o element to be removed from this Vector, if present 800 * @return true if the Vector contained the specified element 801 * @since 1.2 802 */ remove(Object o)803 public boolean remove(Object o) { 804 return removeElement(o); 805 } 806 807 /** 808 * Inserts the specified element at the specified position in this Vector. 809 * Shifts the element currently at that position (if any) and any 810 * subsequent elements to the right (adds one to their indices). 811 * 812 * @param index index at which the specified element is to be inserted 813 * @param element element to be inserted 814 * @throws ArrayIndexOutOfBoundsException if the index is out of range 815 * ({@code index < 0 || index > size()}) 816 * @since 1.2 817 */ add(int index, E element)818 public void add(int index, E element) { 819 insertElementAt(element, index); 820 } 821 822 /** 823 * Removes the element at the specified position in this Vector. 824 * Shifts any subsequent elements to the left (subtracts one from their 825 * indices). Returns the element that was removed from the Vector. 826 * 827 * @throws ArrayIndexOutOfBoundsException if the index is out of range 828 * ({@code index < 0 || index >= size()}) 829 * @param index the index of the element to be removed 830 * @return element that was removed 831 * @since 1.2 832 */ remove(int index)833 public synchronized E remove(int index) { 834 modCount++; 835 if (index >= elementCount) 836 throw new ArrayIndexOutOfBoundsException(index); 837 E oldValue = elementData(index); 838 839 int numMoved = elementCount - index - 1; 840 if (numMoved > 0) 841 System.arraycopy(elementData, index+1, elementData, index, 842 numMoved); 843 elementData[--elementCount] = null; // Let gc do its work 844 845 return oldValue; 846 } 847 848 /** 849 * Removes all of the elements from this Vector. The Vector will 850 * be empty after this call returns (unless it throws an exception). 851 * 852 * @since 1.2 853 */ clear()854 public void clear() { 855 removeAllElements(); 856 } 857 858 // Bulk Operations 859 860 /** 861 * Returns true if this Vector contains all of the elements in the 862 * specified Collection. 863 * 864 * @param c a collection whose elements will be tested for containment 865 * in this Vector 866 * @return true if this Vector contains all of the elements in the 867 * specified collection 868 * @throws NullPointerException if the specified collection is null 869 */ containsAll(Collection<?> c)870 public synchronized boolean containsAll(Collection<?> c) { 871 return super.containsAll(c); 872 } 873 874 /** 875 * Appends all of the elements in the specified Collection to the end of 876 * this Vector, in the order that they are returned by the specified 877 * Collection's Iterator. The behavior of this operation is undefined if 878 * the specified Collection is modified while the operation is in progress. 879 * (This implies that the behavior of this call is undefined if the 880 * specified Collection is this Vector, and this Vector is nonempty.) 881 * 882 * @param c elements to be inserted into this Vector 883 * @return {@code true} if this Vector changed as a result of the call 884 * @throws NullPointerException if the specified collection is null 885 * @since 1.2 886 */ addAll(Collection<? extends E> c)887 public synchronized boolean addAll(Collection<? extends E> c) { 888 modCount++; 889 Object[] a = c.toArray(); 890 int numNew = a.length; 891 ensureCapacityHelper(elementCount + numNew); 892 System.arraycopy(a, 0, elementData, elementCount, numNew); 893 elementCount += numNew; 894 return numNew != 0; 895 } 896 897 /** 898 * Removes from this Vector all of its elements that are contained in the 899 * specified Collection. 900 * 901 * @param c a collection of elements to be removed from the Vector 902 * @return true if this Vector changed as a result of the call 903 * @throws ClassCastException if the types of one or more elements 904 * in this vector are incompatible with the specified 905 * collection 906 * (<a href="Collection.html#optional-restrictions">optional</a>) 907 * @throws NullPointerException if this vector contains one or more null 908 * elements and the specified collection does not support null 909 * elements 910 * (<a href="Collection.html#optional-restrictions">optional</a>), 911 * or if the specified collection is null 912 * @since 1.2 913 */ removeAll(Collection<?> c)914 public synchronized boolean removeAll(Collection<?> c) { 915 return super.removeAll(c); 916 } 917 918 /** 919 * Retains only the elements in this Vector that are contained in the 920 * specified Collection. In other words, removes from this Vector all 921 * of its elements that are not contained in the specified Collection. 922 * 923 * @param c a collection of elements to be retained in this Vector 924 * (all other elements are removed) 925 * @return true if this Vector changed as a result of the call 926 * @throws ClassCastException if the types of one or more elements 927 * in this vector are incompatible with the specified 928 * collection 929 * (<a href="Collection.html#optional-restrictions">optional</a>) 930 * @throws NullPointerException if this vector contains one or more null 931 * elements and the specified collection does not support null 932 * elements 933 * (<a href="Collection.html#optional-restrictions">optional</a>), 934 * or if the specified collection is null 935 * @since 1.2 936 */ retainAll(Collection<?> c)937 public synchronized boolean retainAll(Collection<?> c) { 938 return super.retainAll(c); 939 } 940 941 /** 942 * Inserts all of the elements in the specified Collection into this 943 * Vector at the specified position. Shifts the element currently at 944 * that position (if any) and any subsequent elements to the right 945 * (increases their indices). The new elements will appear in the Vector 946 * in the order that they are returned by the specified Collection's 947 * iterator. 948 * 949 * @param index index at which to insert the first element from the 950 * specified collection 951 * @param c elements to be inserted into this Vector 952 * @return {@code true} if this Vector changed as a result of the call 953 * @throws ArrayIndexOutOfBoundsException if the index is out of range 954 * ({@code index < 0 || index > size()}) 955 * @throws NullPointerException if the specified collection is null 956 * @since 1.2 957 */ addAll(int index, Collection<? extends E> c)958 public synchronized boolean addAll(int index, Collection<? extends E> c) { 959 modCount++; 960 if (index < 0 || index > elementCount) 961 throw new ArrayIndexOutOfBoundsException(index); 962 963 Object[] a = c.toArray(); 964 int numNew = a.length; 965 ensureCapacityHelper(elementCount + numNew); 966 967 int numMoved = elementCount - index; 968 if (numMoved > 0) 969 System.arraycopy(elementData, index, elementData, index + numNew, 970 numMoved); 971 972 System.arraycopy(a, 0, elementData, index, numNew); 973 elementCount += numNew; 974 return numNew != 0; 975 } 976 977 /** 978 * Compares the specified Object with this Vector for equality. Returns 979 * true if and only if the specified Object is also a List, both Lists 980 * have the same size, and all corresponding pairs of elements in the two 981 * Lists are <em>equal</em>. (Two elements {@code e1} and 982 * {@code e2} are <em>equal</em> if {@code (e1==null ? e2==null : 983 * e1.equals(e2))}.) In other words, two Lists are defined to be 984 * equal if they contain the same elements in the same order. 985 * 986 * @param o the Object to be compared for equality with this Vector 987 * @return true if the specified Object is equal to this Vector 988 */ equals(Object o)989 public synchronized boolean equals(Object o) { 990 return super.equals(o); 991 } 992 993 /** 994 * Returns the hash code value for this Vector. 995 */ hashCode()996 public synchronized int hashCode() { 997 return super.hashCode(); 998 } 999 1000 /** 1001 * Returns a string representation of this Vector, containing 1002 * the String representation of each element. 1003 */ toString()1004 public synchronized String toString() { 1005 return super.toString(); 1006 } 1007 1008 /** 1009 * Returns a view of the portion of this List between fromIndex, 1010 * inclusive, and toIndex, exclusive. (If fromIndex and toIndex are 1011 * equal, the returned List is empty.) The returned List is backed by this 1012 * List, so changes in the returned List are reflected in this List, and 1013 * vice-versa. The returned List supports all of the optional List 1014 * operations supported by this List. 1015 * 1016 * <p>This method eliminates the need for explicit range operations (of 1017 * the sort that commonly exist for arrays). Any operation that expects 1018 * a List can be used as a range operation by operating on a subList view 1019 * instead of a whole List. For example, the following idiom 1020 * removes a range of elements from a List: 1021 * <pre> 1022 * list.subList(from, to).clear(); 1023 * </pre> 1024 * Similar idioms may be constructed for indexOf and lastIndexOf, 1025 * and all of the algorithms in the Collections class can be applied to 1026 * a subList. 1027 * 1028 * <p>The semantics of the List returned by this method become undefined if 1029 * the backing list (i.e., this List) is <i>structurally modified</i> in 1030 * any way other than via the returned List. (Structural modifications are 1031 * those that change the size of the List, or otherwise perturb it in such 1032 * a fashion that iterations in progress may yield incorrect results.) 1033 * 1034 * @param fromIndex low endpoint (inclusive) of the subList 1035 * @param toIndex high endpoint (exclusive) of the subList 1036 * @return a view of the specified range within this List 1037 * @throws IndexOutOfBoundsException if an endpoint index value is out of range 1038 * {@code (fromIndex < 0 || toIndex > size)} 1039 * @throws IllegalArgumentException if the endpoint indices are out of order 1040 * {@code (fromIndex > toIndex)} 1041 */ subList(int fromIndex, int toIndex)1042 public synchronized List<E> subList(int fromIndex, int toIndex) { 1043 return Collections.synchronizedList(super.subList(fromIndex, toIndex), 1044 this); 1045 } 1046 1047 /** 1048 * Removes from this list all of the elements whose index is between 1049 * {@code fromIndex}, inclusive, and {@code toIndex}, exclusive. 1050 * Shifts any succeeding elements to the left (reduces their index). 1051 * This call shortens the list by {@code (toIndex - fromIndex)} elements. 1052 * (If {@code toIndex==fromIndex}, this operation has no effect.) 1053 */ removeRange(int fromIndex, int toIndex)1054 protected synchronized void removeRange(int fromIndex, int toIndex) { 1055 modCount++; 1056 int numMoved = elementCount - toIndex; 1057 System.arraycopy(elementData, toIndex, elementData, fromIndex, 1058 numMoved); 1059 1060 // Let gc do its work 1061 int newElementCount = elementCount - (toIndex-fromIndex); 1062 while (elementCount != newElementCount) 1063 elementData[--elementCount] = null; 1064 } 1065 1066 /** 1067 * Loads a {@code Vector} instance from a stream 1068 * (that is, deserializes it). 1069 * This method performs checks to ensure the consistency 1070 * of the fields. 1071 * 1072 * @param in the stream 1073 * @throws java.io.IOException if an I/O error occurs 1074 * @throws ClassNotFoundException if the stream contains data 1075 * of a non-existing class 1076 */ readObject(ObjectInputStream in)1077 private void readObject(ObjectInputStream in) 1078 throws IOException, ClassNotFoundException { 1079 ObjectInputStream.GetField gfields = in.readFields(); 1080 int count = gfields.get("elementCount", 0); 1081 Object[] data = (Object[])gfields.get("elementData", null); 1082 if (count < 0 || data == null || count > data.length) { 1083 throw new StreamCorruptedException("Inconsistent vector internals"); 1084 } 1085 elementCount = count; 1086 elementData = data.clone(); 1087 } 1088 1089 /** 1090 * Save the state of the {@code Vector} instance to a stream (that 1091 * is, serialize it). 1092 * This method performs synchronization to ensure the consistency 1093 * of the serialized data. 1094 */ writeObject(java.io.ObjectOutputStream s)1095 private void writeObject(java.io.ObjectOutputStream s) 1096 throws java.io.IOException { 1097 final java.io.ObjectOutputStream.PutField fields = s.putFields(); 1098 final Object[] data; 1099 synchronized (this) { 1100 fields.put("capacityIncrement", capacityIncrement); 1101 fields.put("elementCount", elementCount); 1102 data = elementData.clone(); 1103 } 1104 fields.put("elementData", data); 1105 s.writeFields(); 1106 } 1107 1108 /** 1109 * Returns a list iterator over the elements in this list (in proper 1110 * sequence), starting at the specified position in the list. 1111 * The specified index indicates the first element that would be 1112 * returned by an initial call to {@link ListIterator#next next}. 1113 * An initial call to {@link ListIterator#previous previous} would 1114 * return the element with the specified index minus one. 1115 * 1116 * <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>. 1117 * 1118 * @throws IndexOutOfBoundsException {@inheritDoc} 1119 */ listIterator(int index)1120 public synchronized ListIterator<E> listIterator(int index) { 1121 if (index < 0 || index > elementCount) 1122 throw new IndexOutOfBoundsException("Index: "+index); 1123 return new ListItr(index); 1124 } 1125 1126 /** 1127 * Returns a list iterator over the elements in this list (in proper 1128 * sequence). 1129 * 1130 * <p>The returned list iterator is <a href="#fail-fast"><i>fail-fast</i></a>. 1131 * 1132 * @see #listIterator(int) 1133 */ listIterator()1134 public synchronized ListIterator<E> listIterator() { 1135 return new ListItr(0); 1136 } 1137 1138 /** 1139 * Returns an iterator over the elements in this list in proper sequence. 1140 * 1141 * <p>The returned iterator is <a href="#fail-fast"><i>fail-fast</i></a>. 1142 * 1143 * @return an iterator over the elements in this list in proper sequence 1144 */ iterator()1145 public synchronized Iterator<E> iterator() { 1146 return new Itr(); 1147 } 1148 1149 /** 1150 * An optimized version of AbstractList.Itr 1151 */ 1152 private class Itr implements Iterator<E> { 1153 int cursor; // index of next element to return 1154 int lastRet = -1; // index of last element returned; -1 if no such 1155 int expectedModCount = modCount; 1156 hasNext()1157 public boolean hasNext() { 1158 // Racy but within spec, since modifications are checked 1159 // within or after synchronization in next/previous 1160 return cursor != elementCount; 1161 } 1162 next()1163 public E next() { 1164 synchronized (Vector.this) { 1165 checkForComodification(); 1166 int i = cursor; 1167 if (i >= elementCount) 1168 throw new NoSuchElementException(); 1169 cursor = i + 1; 1170 return elementData(lastRet = i); 1171 } 1172 } 1173 remove()1174 public void remove() { 1175 if (lastRet == -1) 1176 throw new IllegalStateException(); 1177 synchronized (Vector.this) { 1178 checkForComodification(); 1179 Vector.this.remove(lastRet); 1180 expectedModCount = modCount; 1181 } 1182 cursor = lastRet; 1183 lastRet = -1; 1184 } 1185 1186 @Override forEachRemaining(Consumer<? super E> action)1187 public void forEachRemaining(Consumer<? super E> action) { 1188 Objects.requireNonNull(action); 1189 synchronized (Vector.this) { 1190 final int size = elementCount; 1191 int i = cursor; 1192 if (i >= size) { 1193 return; 1194 } 1195 @SuppressWarnings("unchecked") 1196 final E[] elementData = (E[]) Vector.this.elementData; 1197 if (i >= elementData.length) { 1198 throw new ConcurrentModificationException(); 1199 } 1200 while (i != size && modCount == expectedModCount) { 1201 action.accept(elementData[i++]); 1202 } 1203 // update once at end of iteration to reduce heap write traffic 1204 cursor = i; 1205 lastRet = i - 1; 1206 checkForComodification(); 1207 } 1208 } 1209 checkForComodification()1210 final void checkForComodification() { 1211 if (modCount != expectedModCount) 1212 throw new ConcurrentModificationException(); 1213 } 1214 } 1215 1216 /** 1217 * An optimized version of AbstractList.ListItr 1218 */ 1219 final class ListItr extends Itr implements ListIterator<E> { ListItr(int index)1220 ListItr(int index) { 1221 super(); 1222 cursor = index; 1223 } 1224 hasPrevious()1225 public boolean hasPrevious() { 1226 return cursor != 0; 1227 } 1228 nextIndex()1229 public int nextIndex() { 1230 return cursor; 1231 } 1232 previousIndex()1233 public int previousIndex() { 1234 return cursor - 1; 1235 } 1236 previous()1237 public E previous() { 1238 synchronized (Vector.this) { 1239 checkForComodification(); 1240 int i = cursor - 1; 1241 if (i < 0) 1242 throw new NoSuchElementException(); 1243 cursor = i; 1244 return elementData(lastRet = i); 1245 } 1246 } 1247 set(E e)1248 public void set(E e) { 1249 if (lastRet == -1) 1250 throw new IllegalStateException(); 1251 synchronized (Vector.this) { 1252 checkForComodification(); 1253 Vector.this.set(lastRet, e); 1254 } 1255 } 1256 add(E e)1257 public void add(E e) { 1258 int i = cursor; 1259 synchronized (Vector.this) { 1260 checkForComodification(); 1261 Vector.this.add(i, e); 1262 expectedModCount = modCount; 1263 } 1264 cursor = i + 1; 1265 lastRet = -1; 1266 } 1267 } 1268 1269 @Override forEach(Consumer<? super E> action)1270 public synchronized void forEach(Consumer<? super E> action) { 1271 Objects.requireNonNull(action); 1272 final int expectedModCount = modCount; 1273 @SuppressWarnings("unchecked") 1274 final E[] elementData = (E[]) this.elementData; 1275 final int elementCount = this.elementCount; 1276 for (int i=0; modCount == expectedModCount && i < elementCount; i++) { 1277 action.accept(elementData[i]); 1278 } 1279 if (modCount != expectedModCount) { 1280 throw new ConcurrentModificationException(); 1281 } 1282 } 1283 1284 @Override 1285 @SuppressWarnings("unchecked") removeIf(Predicate<? super E> filter)1286 public synchronized boolean removeIf(Predicate<? super E> filter) { 1287 Objects.requireNonNull(filter); 1288 // figure out which elements are to be removed 1289 // any exception thrown from the filter predicate at this stage 1290 // will leave the collection unmodified 1291 int removeCount = 0; 1292 final int size = elementCount; 1293 final BitSet removeSet = new BitSet(size); 1294 final int expectedModCount = modCount; 1295 for (int i=0; modCount == expectedModCount && i < size; i++) { 1296 @SuppressWarnings("unchecked") 1297 final E element = (E) elementData[i]; 1298 if (filter.test(element)) { 1299 removeSet.set(i); 1300 removeCount++; 1301 } 1302 } 1303 if (modCount != expectedModCount) { 1304 throw new ConcurrentModificationException(); 1305 } 1306 1307 // shift surviving elements left over the spaces left by removed elements 1308 final boolean anyToRemove = removeCount > 0; 1309 if (anyToRemove) { 1310 final int newSize = size - removeCount; 1311 for (int i=0, j=0; (i < size) && (j < newSize); i++, j++) { 1312 i = removeSet.nextClearBit(i); 1313 elementData[j] = elementData[i]; 1314 } 1315 for (int k=newSize; k < size; k++) { 1316 elementData[k] = null; // Let gc do its work 1317 } 1318 elementCount = newSize; 1319 if (modCount != expectedModCount) { 1320 throw new ConcurrentModificationException(); 1321 } 1322 modCount++; 1323 } 1324 1325 return anyToRemove; 1326 } 1327 1328 @Override 1329 @SuppressWarnings("unchecked") replaceAll(UnaryOperator<E> operator)1330 public synchronized void replaceAll(UnaryOperator<E> operator) { 1331 Objects.requireNonNull(operator); 1332 final int expectedModCount = modCount; 1333 final int size = elementCount; 1334 for (int i=0; modCount == expectedModCount && i < size; i++) { 1335 elementData[i] = operator.apply((E) elementData[i]); 1336 } 1337 if (modCount != expectedModCount) { 1338 throw new ConcurrentModificationException(); 1339 } 1340 modCount++; 1341 } 1342 1343 @SuppressWarnings("unchecked") 1344 @Override sort(Comparator<? super E> c)1345 public synchronized void sort(Comparator<? super E> c) { 1346 final int expectedModCount = modCount; 1347 Arrays.sort((E[]) elementData, 0, elementCount, c); 1348 if (modCount != expectedModCount) { 1349 throw new ConcurrentModificationException(); 1350 } 1351 modCount++; 1352 } 1353 1354 /** 1355 * Creates a <em><a href="Spliterator.html#binding">late-binding</a></em> 1356 * and <em>fail-fast</em> {@link Spliterator} over the elements in this 1357 * list. 1358 * 1359 * <p>The {@code Spliterator} reports {@link Spliterator#SIZED}, 1360 * {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}. 1361 * Overriding implementations should document the reporting of additional 1362 * characteristic values. 1363 * 1364 * @return a {@code Spliterator} over the elements in this list 1365 * @since 1.8 1366 */ 1367 @Override spliterator()1368 public Spliterator<E> spliterator() { 1369 return new VectorSpliterator<>(this, null, 0, -1, 0); 1370 } 1371 1372 /** Similar to ArrayList Spliterator */ 1373 static final class VectorSpliterator<E> implements Spliterator<E> { 1374 private final Vector<E> list; 1375 private Object[] array; 1376 private int index; // current index, modified on advance/split 1377 private int fence; // -1 until used; then one past last index 1378 private int expectedModCount; // initialized when fence set 1379 1380 /** Create new spliterator covering the given range */ VectorSpliterator(Vector<E> list, Object[] array, int origin, int fence, int expectedModCount)1381 VectorSpliterator(Vector<E> list, Object[] array, int origin, int fence, 1382 int expectedModCount) { 1383 this.list = list; 1384 this.array = array; 1385 this.index = origin; 1386 this.fence = fence; 1387 this.expectedModCount = expectedModCount; 1388 } 1389 getFence()1390 private int getFence() { // initialize on first use 1391 int hi; 1392 if ((hi = fence) < 0) { 1393 synchronized(list) { 1394 array = list.elementData; 1395 expectedModCount = list.modCount; 1396 hi = fence = list.elementCount; 1397 } 1398 } 1399 return hi; 1400 } 1401 trySplit()1402 public Spliterator<E> trySplit() { 1403 int hi = getFence(), lo = index, mid = (lo + hi) >>> 1; 1404 return (lo >= mid) ? null : 1405 new VectorSpliterator<E>(list, array, lo, index = mid, 1406 expectedModCount); 1407 } 1408 1409 @SuppressWarnings("unchecked") tryAdvance(Consumer<? super E> action)1410 public boolean tryAdvance(Consumer<? super E> action) { 1411 int i; 1412 if (action == null) 1413 throw new NullPointerException(); 1414 if (getFence() > (i = index)) { 1415 index = i + 1; 1416 action.accept((E)array[i]); 1417 if (list.modCount != expectedModCount) 1418 throw new ConcurrentModificationException(); 1419 return true; 1420 } 1421 return false; 1422 } 1423 1424 @SuppressWarnings("unchecked") forEachRemaining(Consumer<? super E> action)1425 public void forEachRemaining(Consumer<? super E> action) { 1426 int i, hi; // hoist accesses and checks from loop 1427 Vector<E> lst; Object[] a; 1428 if (action == null) 1429 throw new NullPointerException(); 1430 if ((lst = list) != null) { 1431 if ((hi = fence) < 0) { 1432 synchronized(lst) { 1433 expectedModCount = lst.modCount; 1434 a = array = lst.elementData; 1435 hi = fence = lst.elementCount; 1436 } 1437 } 1438 else 1439 a = array; 1440 if (a != null && (i = index) >= 0 && (index = hi) <= a.length) { 1441 while (i < hi) 1442 action.accept((E) a[i++]); 1443 if (lst.modCount == expectedModCount) 1444 return; 1445 } 1446 } 1447 throw new ConcurrentModificationException(); 1448 } 1449 estimateSize()1450 public long estimateSize() { 1451 return (long) (getFence() - index); 1452 } 1453 characteristics()1454 public int characteristics() { 1455 return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED; 1456 } 1457 } 1458 } 1459