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Comparing jsr166/src/main/java/util/ArrayList.java (file contents):
Revision 1.25 by jsr166, Tue Sep 11 15:38:02 2007 UTC vs.
Revision 1.38 by jsr166, Sat Nov 12 20:51:59 2016 UTC

#	Line 1 | Line 1
1		/*
2	<	* Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
2	>	* Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3		* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4		*
5		* 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.  Sun designates this
7	>	* published by the Free Software Foundation.  Oracle designates this
8		* particular file as subject to the "Classpath" exception as provided
9	<	* by Sun in the LICENSE file that accompanied this code.
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
#	Line 18 | Line 18
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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22	<	* CA 95054 USA or visit www.sun.com if you need additional information or
23	<	* have any questions.
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.util.function.Consumer;
29	+	import java.util.function.Predicate;
30	+	import java.util.function.UnaryOperator;
31	+
32		/**
33	<	* Resizable-array implementation of the <tt>List</tt> interface.  Implements
33	>	* Resizable-array implementation of the {@code List} interface.  Implements
34		* all optional list operations, and permits all elements, including
35	<	* <tt>null</tt>.  In addition to implementing the <tt>List</tt> interface,
35	>	* {@code null}.  In addition to implementing the {@code List} interface,
36		* this class provides methods to manipulate the size of the array that is
37		* used internally to store the list.  (This class is roughly equivalent to
38	<	* <tt>Vector</tt>, except that it is unsynchronized.)
38	>	* {@code Vector}, except that it is unsynchronized.)
39		*
40	<	* <p>The <tt>size</tt>, <tt>isEmpty</tt>, <tt>get</tt>, <tt>set</tt>,
41	<	* <tt>iterator</tt>, and <tt>listIterator</tt> operations run in constant
42	<	* time.  The <tt>add</tt> operation runs in <i>amortized constant time</i>,
40	>	* <p>The {@code size}, {@code isEmpty}, {@code get}, {@code set},
41	>	* {@code iterator}, and {@code listIterator} operations run in constant
42	>	* time.  The {@code add} operation runs in <i>amortized constant time</i>,
43		* that is, adding n elements requires O(n) time.  All of the other operations
44		* run in linear time (roughly speaking).  The constant factor is low compared
45	<	* to that for the <tt>LinkedList</tt> implementation.
45	>	* to that for the {@code LinkedList} implementation.
46		*
47	<	* <p>Each <tt>ArrayList</tt> instance has a <i>capacity</i>.  The capacity is
47	>	* <p>Each {@code ArrayList} instance has a <i>capacity</i>.  The capacity is
48		* the size of the array used to store the elements in the list.  It is always
49		* at least as large as the list size.  As elements are added to an ArrayList,
50		* its capacity grows automatically.  The details of the growth policy are not
51		* specified beyond the fact that adding an element has constant amortized
52		* time cost.
53		*
54	<	* <p>An application can increase the capacity of an <tt>ArrayList</tt> instance
55	<	* before adding a large number of elements using the <tt>ensureCapacity</tt>
54	>	* <p>An application can increase the capacity of an {@code ArrayList} instance
55	>	* before adding a large number of elements using the {@code ensureCapacity}
56		* operation.  This may reduce the amount of incremental reallocation.
57		*
58		* <p><strong>Note that this implementation is not synchronized.</strong>
59	<	* If multiple threads access an <tt>ArrayList</tt> instance concurrently,
59	>	* If multiple threads access an {@code ArrayList} instance concurrently,
60		* and at least one of the threads modifies the list structurally, it
61		* <i>must</i> be synchronized externally.  (A structural modification is
62		* any operation that adds or deletes one or more elements, or explicitly
#	Line 66 | Line 70 | package java.util;
70		* unsynchronized access to the list:<pre>
71		*   List list = Collections.synchronizedList(new ArrayList(...));</pre>
72		*
73	<	* <p><a name="fail-fast"/>
73	>	* <p id="fail-fast">
74		* The iterators returned by this class's {@link #iterator() iterator} and
75		* {@link #listIterator(int) listIterator} methods are <em>fail-fast</em>:
76		* if the list is structurally modified at any time after the iterator is
#	Line 90 | Line 94 | package java.util;
94		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
95		* Java Collections Framework</a>.
96		*
97	+	* @param <E> the type of elements in this list
98	+	*
99		* @author  Josh Bloch
100		* @author  Neal Gafter
101	<	* @version %I%, %G%
102	<	* @see     Collection
103	<	* @see     List
104	<	* @see     LinkedList
99	<	* @see     Vector
101	>	* @see     Collection
102	>	* @see     List
103	>	* @see     LinkedList
104	>	* @see     Vector
105		* @since   1.2
106		*/
102	–
107		public class ArrayList<E> extends AbstractList<E>
108		implements List<E>, RandomAccess, Cloneable, java.io.Serializable
109		{
110		private static final long serialVersionUID = 8683452581122892189L;
111
112		/**
113	+	* Default initial capacity.
114	+	*/
115	+	private static final int DEFAULT_CAPACITY = 10;
116	+
117	+	/**
118	+	* Shared empty array instance used for empty instances.
119	+	*/
120	+	private static final Object[] EMPTY_ELEMENTDATA = {};
121	+
122	+	/**
123	+	* Shared empty array instance used for default sized empty instances. We
124	+	* distinguish this from EMPTY_ELEMENTDATA to know how much to inflate when
125	+	* first element is added.
126	+	*/
127	+	private static final Object[] DEFAULTCAPACITY_EMPTY_ELEMENTDATA = {};
128	+
129	+	/**
130		* The array buffer into which the elements of the ArrayList are stored.
131	<	* The capacity of the ArrayList is the length of this array buffer.
131	>	* The capacity of the ArrayList is the length of this array buffer. Any
132	>	* empty ArrayList with elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
133	>	* will be expanded to DEFAULT_CAPACITY when the first element is added.
134		*/
135	<	private transient Object[] elementData;
135	>	transient Object[] elementData; // non-private to simplify nested class access
136
137		/**
138		* The size of the ArrayList (the number of elements it contains).
#	Line 121 | Line 144 | public class ArrayList<E> extends Abstra
144		/**
145		* Constructs an empty list with the specified initial capacity.
146		*
147	<	* @param   initialCapacity   the initial capacity of the list
148	<	* @exception IllegalArgumentException if the specified initial capacity
149	<	*            is negative
147	>	* @param  initialCapacity  the initial capacity of the list
148	>	* @throws IllegalArgumentException if the specified initial capacity
149	>	*         is negative
150		*/
151		public ArrayList(int initialCapacity) {
152	<	super();
153	<	if (initialCapacity < 0)
152	>	if (initialCapacity > 0) {
153	>	this.elementData = new Object[initialCapacity];
154	>	} else if (initialCapacity == 0) {
155	>	this.elementData = EMPTY_ELEMENTDATA;
156	>	} else {
157		throw new IllegalArgumentException("Illegal Capacity: "+
158		initialCapacity);
159	<	this.elementData = new Object[initialCapacity];
159	>	}
160		}
161
162		/**
163		* Constructs an empty list with an initial capacity of ten.
164		*/
165		public ArrayList() {
166	<	this(10);
166	>	this.elementData = DEFAULTCAPACITY_EMPTY_ELEMENTDATA;
167		}
168
169		/**
#	Line 149 | Line 175 | public class ArrayList<E> extends Abstra
175		* @throws NullPointerException if the specified collection is null
176		*/
177		public ArrayList(Collection<? extends E> c) {
178	<	elementData = c.toArray();
179	<	size = elementData.length;
180	<	// c.toArray might (incorrectly) not return Object[] (see 6260652)
181	<	if (elementData.getClass() != Object[].class)
182	<	elementData = Arrays.copyOf(elementData, size, Object[].class);
178	>	elementData = c.toArray();
179	>	if ((size = elementData.length) != 0) {
180	>	// defend against c.toArray (incorrectly) not returning Object[]
181	>	// (see e.g. https://bugs.openjdk.java.net/browse/JDK-6260652)
182	>	if (elementData.getClass() != Object[].class)
183	>	elementData = Arrays.copyOf(elementData, size, Object[].class);
184	>	} else {
185	>	// replace with empty array.
186	>	this.elementData = EMPTY_ELEMENTDATA;
187	>	}
188		}
189
190		/**
191	<	* Trims the capacity of this <tt>ArrayList</tt> instance to be the
191	>	* Trims the capacity of this {@code ArrayList} instance to be the
192		* list's current size.  An application can use this operation to minimize
193	<	* the storage of an <tt>ArrayList</tt> instance.
193	>	* the storage of an {@code ArrayList} instance.
194		*/
195		public void trimToSize() {
196	<	modCount++;
197	<	int oldCapacity = elementData.length;
198	<	if (size < oldCapacity) {
199	<	elementData = Arrays.copyOf(elementData, size);
200	<	}
196	>	modCount++;
197	>	if (size < elementData.length) {
198	>	elementData = (size == 0)
199	>	? EMPTY_ELEMENTDATA
200	>	: Arrays.copyOf(elementData, size);
201	>	}
202		}
203
204		/**
205	<	* Increases the capacity of this <tt>ArrayList</tt> instance, if
205	>	* Increases the capacity of this {@code ArrayList} instance, if
206		* necessary, to ensure that it can hold at least the number of elements
207		* specified by the minimum capacity argument.
208		*
209	<	* @param   minCapacity   the desired minimum capacity
209	>	* @param minCapacity the desired minimum capacity
210		*/
211		public void ensureCapacity(int minCapacity) {
212	<	modCount++;
213	<	int oldCapacity = elementData.length;
214	<	if (minCapacity > oldCapacity) {
215	<	Object oldData[] = elementData;
216	<	int newCapacity = (oldCapacity * 3)/2 + 1;
217	<	if (newCapacity < minCapacity)
218	<	newCapacity = minCapacity;
219	<	// minCapacity is usually close to size, so this is a win:
220	<	elementData = Arrays.copyOf(elementData, newCapacity);
221	<	}
212	>	if (minCapacity > elementData.length
213	>	&& !(elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
214	>	&& minCapacity <= DEFAULT_CAPACITY)) {
215	>	modCount++;
216	>	grow(minCapacity);
217	>	}
218	>	}
219	>
220	>	/**
221	>	* The maximum size of array to allocate (unless necessary).
222	>	* Some VMs reserve some header words in an array.
223	>	* Attempts to allocate larger arrays may result in
224	>	* OutOfMemoryError: Requested array size exceeds VM limit
225	>	*/
226	>	private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
227	>
228	>	/**
229	>	* Increases the capacity to ensure that it can hold at least the
230	>	* number of elements specified by the minimum capacity argument.
231	>	*
232	>	* @param minCapacity the desired minimum capacity
233	>	* @throws OutOfMemoryError if minCapacity is less than zero
234	>	*/
235	>	private Object[] grow(int minCapacity) {
236	>	return elementData = Arrays.copyOf(elementData,
237	>	newCapacity(minCapacity));
238	>	}
239	>
240	>	private Object[] grow() {
241	>	return grow(size + 1);
242	>	}
243	>
244	>	/**
245	>	* Returns a capacity at least as large as the given minimum capacity.
246	>	* Returns the current capacity increased by 50% if that suffices.
247	>	* Will not return a capacity greater than MAX_ARRAY_SIZE unless
248	>	* the given minimum capacity is greater than MAX_ARRAY_SIZE.
249	>	*
250	>	* @param minCapacity the desired minimum capacity
251	>	* @throws OutOfMemoryError if minCapacity is less than zero
252	>	*/
253	>	private int newCapacity(int minCapacity) {
254	>	// overflow-conscious code
255	>	int oldCapacity = elementData.length;
256	>	int newCapacity = oldCapacity + (oldCapacity >> 1);
257	>	if (newCapacity - minCapacity <= 0) {
258	>	if (elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA)
259	>	return Math.max(DEFAULT_CAPACITY, minCapacity);
260	>	if (minCapacity < 0) // overflow
261	>	throw new OutOfMemoryError();
262	>	return minCapacity;
263	>	}
264	>	return (newCapacity - MAX_ARRAY_SIZE <= 0)
265	>	? newCapacity
266	>	: hugeCapacity(minCapacity);
267	>	}
268	>
269	>	private static int hugeCapacity(int minCapacity) {
270	>	if (minCapacity < 0) // overflow
271	>	throw new OutOfMemoryError();
272	>	return (minCapacity > MAX_ARRAY_SIZE)
273	>	? Integer.MAX_VALUE
274	>	: MAX_ARRAY_SIZE;
275		}
276
277		/**
#	Line 195 | Line 280 | public class ArrayList<E> extends Abstra
280		* @return the number of elements in this list
281		*/
282		public int size() {
283	<	return size;
283	>	return size;
284		}
285
286		/**
287	<	* Returns <tt>true</tt> if this list contains no elements.
287	>	* Returns {@code true} if this list contains no elements.
288		*
289	<	* @return <tt>true</tt> if this list contains no elements
289	>	* @return {@code true} if this list contains no elements
290		*/
291		public boolean isEmpty() {
292	<	return size == 0;
292	>	return size == 0;
293		}
294
295		/**
296	<	* Returns <tt>true</tt> if this list contains the specified element.
297	<	* More formally, returns <tt>true</tt> if and only if this list contains
298	<	* at least one element <tt>e</tt> such that
299	<	* <tt>(o==null&nbsp;?&nbsp;e==null&nbsp;:&nbsp;o.equals(e))</tt>.
296	>	* Returns {@code true} if this list contains the specified element.
297	>	* More formally, returns {@code true} if and only if this list contains
298	>	* at least one element {@code e} such that
299	>	* {@code Objects.equals(o, e)}.
300		*
301		* @param o element whose presence in this list is to be tested
302	<	* @return <tt>true</tt> if this list contains the specified element
302	>	* @return {@code true} if this list contains the specified element
303		*/
304		public boolean contains(Object o) {
305	<	return indexOf(o) >= 0;
305	>	return indexOf(o) >= 0;
306		}
307
308		/**
309		* Returns the index of the first occurrence of the specified element
310		* in this list, or -1 if this list does not contain the element.
311	<	* More formally, returns the lowest index <tt>i</tt> such that
312	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
311	>	* More formally, returns the lowest index {@code i} such that
312	>	* {@code Objects.equals(o, get(i))},
313		* or -1 if there is no such index.
314		*/
315		public int indexOf(Object o) {
316	<	if (o == null) {
317	<	for (int i = 0; i < size; i++)
318	<	if (elementData[i]==null)
319	<	return i;
320	<	} else {
321	<	for (int i = 0; i < size; i++)
322	<	if (o.equals(elementData[i]))
323	<	return i;
324	<	}
325	<	return -1;
316	>	if (o == null) {
317	>	for (int i = 0; i < size; i++)
318	>	if (elementData[i]==null)
319	>	return i;
320	>	} else {
321	>	for (int i = 0; i < size; i++)
322	>	if (o.equals(elementData[i]))
323	>	return i;
324	>	}
325	>	return -1;
326		}
327
328		/**
329		* Returns the index of the last occurrence of the specified element
330		* in this list, or -1 if this list does not contain the element.
331	<	* More formally, returns the highest index <tt>i</tt> such that
332	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
331	>	* More formally, returns the highest index {@code i} such that
332	>	* {@code Objects.equals(o, get(i))},
333		* or -1 if there is no such index.
334		*/
335		public int lastIndexOf(Object o) {
336	<	if (o == null) {
337	<	for (int i = size-1; i >= 0; i--)
338	<	if (elementData[i]==null)
339	<	return i;
340	<	} else {
341	<	for (int i = size-1; i >= 0; i--)
342	<	if (o.equals(elementData[i]))
343	<	return i;
344	<	}
345	<	return -1;
336	>	if (o == null) {
337	>	for (int i = size-1; i >= 0; i--)
338	>	if (elementData[i]==null)
339	>	return i;
340	>	} else {
341	>	for (int i = size-1; i >= 0; i--)
342	>	if (o.equals(elementData[i]))
343	>	return i;
344	>	}
345	>	return -1;
346		}
347
348		/**
349	<	* Returns a shallow copy of this <tt>ArrayList</tt> instance.  (The
349	>	* Returns a shallow copy of this {@code ArrayList} instance.  (The
350		* elements themselves are not copied.)
351		*
352	<	* @return a clone of this <tt>ArrayList</tt> instance
352	>	* @return a clone of this {@code ArrayList} instance
353		*/
354		public Object clone() {
355	<	try {
356	<	@SuppressWarnings("unchecked")
357	<	ArrayList<E> v = (ArrayList<E>) super.clone();
358	<	v.elementData = Arrays.copyOf(elementData, size);
359	<	v.modCount = 0;
360	<	return v;
361	<	} catch (CloneNotSupportedException e) {
362	<	// this shouldn't happen, since we are Cloneable
363	<	throw new InternalError();
279	<	}
355	>	try {
356	>	ArrayList<?> v = (ArrayList<?>) super.clone();
357	>	v.elementData = Arrays.copyOf(elementData, size);
358	>	v.modCount = 0;
359	>	return v;
360	>	} catch (CloneNotSupportedException e) {
361	>	// this shouldn't happen, since we are Cloneable
362	>	throw new InternalError(e);
363	>	}
364		}
365
366		/**
#	Line 308 | Line 392 | public class ArrayList<E> extends Abstra
392		* <p>If the list fits in the specified array with room to spare
393		* (i.e., the array has more elements than the list), the element in
394		* the array immediately following the end of the collection is set to
395	<	* <tt>null</tt>.  (This is useful in determining the length of the
395	>	* {@code null}.  (This is useful in determining the length of the
396		* list <i>only</i> if the caller knows that the list does not contain
397		* any null elements.)
398		*
#	Line 326 | Line 410 | public class ArrayList<E> extends Abstra
410		if (a.length < size)
411		// Make a new array of a's runtime type, but my contents:
412		return (T[]) Arrays.copyOf(elementData, size, a.getClass());
413	<	System.arraycopy(elementData, 0, a, 0, size);
413	>	System.arraycopy(elementData, 0, a, 0, size);
414		if (a.length > size)
415		a[size] = null;
416		return a;
#	Line 336 | Line 420 | public class ArrayList<E> extends Abstra
420
421		@SuppressWarnings("unchecked")
422		E elementData(int index) {
423	<	return (E) elementData[index];
423	>	return (E) elementData[index];
424		}
425
426		/**
#	Line 347 | Line 431 | public class ArrayList<E> extends Abstra
431		* @throws IndexOutOfBoundsException {@inheritDoc}
432		*/
433		public E get(int index) {
434	<	rangeCheck(index);
435	<
352	<	return elementData(index);
434	>	Objects.checkIndex(index, size);
435	>	return elementData(index);
436		}
437
438		/**
#	Line 362 | Line 445 | public class ArrayList<E> extends Abstra
445		* @throws IndexOutOfBoundsException {@inheritDoc}
446		*/
447		public E set(int index, E element) {
448	<	rangeCheck(index);
448	>	Objects.checkIndex(index, size);
449	>	E oldValue = elementData(index);
450	>	elementData[index] = element;
451	>	return oldValue;
452	>	}
453
454	<	E oldValue = elementData(index);
455	<	elementData[index] = element;
456	<	return oldValue;
454	>	/**
455	>	* This helper method split out from add(E) to keep method
456	>	* bytecode size under 35 (the -XX:MaxInlineSize default value),
457	>	* which helps when add(E) is called in a C1-compiled loop.
458	>	*/
459	>	private void add(E e, Object[] elementData, int s) {
460	>	if (s == elementData.length)
461	>	elementData = grow();
462	>	elementData[s] = e;
463	>	size = s + 1;
464		}
465
466		/**
467		* Appends the specified element to the end of this list.
468		*
469		* @param e element to be appended to this list
470	<	* @return <tt>true</tt> (as specified by {@link Collection#add})
470	>	* @return {@code true} (as specified by {@link Collection#add})
471		*/
472		public boolean add(E e) {
473	<	ensureCapacity(size + 1);  // Increments modCount!!
474	<	elementData[size++] = e;
475	<	return true;
473	>	modCount++;
474	>	add(e, elementData, size);
475	>	return true;
476		}
477
478		/**
#	Line 391 | Line 485 | public class ArrayList<E> extends Abstra
485		* @throws IndexOutOfBoundsException {@inheritDoc}
486		*/
487		public void add(int index, E element) {
488	<	rangeCheckForAdd(index);
489	<
490	<	ensureCapacity(size+1);  // Increments modCount!!
491	<	System.arraycopy(elementData, index, elementData, index + 1,
492	<	size - index);
493	<	elementData[index] = element;
494	<	size++;
488	>	rangeCheckForAdd(index);
489	>	modCount++;
490	>	final int s;
491	>	Object[] elementData;
492	>	if ((s = size) == (elementData = this.elementData).length)
493	>	elementData = grow();
494	>	System.arraycopy(elementData, index,
495	>	elementData, index + 1,
496	>	s - index);
497	>	elementData[index] = element;
498	>	size = s + 1;
499		}
500
501		/**
#	Line 410 | Line 508 | public class ArrayList<E> extends Abstra
508		* @throws IndexOutOfBoundsException {@inheritDoc}
509		*/
510		public E remove(int index) {
511	<	rangeCheck(index);
511	>	Objects.checkIndex(index, size);
512
513	<	modCount++;
514	<	E oldValue = elementData(index);
513	>	modCount++;
514	>	E oldValue = elementData(index);
515
516	<	int numMoved = size - index - 1;
517	<	if (numMoved > 0)
518	<	System.arraycopy(elementData, index+1, elementData, index,
519	<	numMoved);
520	<	elementData[--size] = null; // Let gc do its work
516	>	int numMoved = size - index - 1;
517	>	if (numMoved > 0)
518	>	System.arraycopy(elementData, index+1, elementData, index,
519	>	numMoved);
520	>	elementData[--size] = null; // clear to let GC do its work
521
522	<	return oldValue;
522	>	return oldValue;
523		}
524
525		/**
526		* Removes the first occurrence of the specified element from this list,
527		* if it is present.  If the list does not contain the element, it is
528		* unchanged.  More formally, removes the element with the lowest index
529	<	* <tt>i</tt> such that
530	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>
531	<	* (if such an element exists).  Returns <tt>true</tt> if this list
529	>	* {@code i} such that
530	>	* {@code Objects.equals(o, get(i))}
531	>	* (if such an element exists).  Returns {@code true} if this list
532		* contained the specified element (or equivalently, if this list
533		* changed as a result of the call).
534		*
535		* @param o element to be removed from this list, if present
536	<	* @return <tt>true</tt> if this list contained the specified element
536	>	* @return {@code true} if this list contained the specified element
537		*/
538		public boolean remove(Object o) {
539	<	if (o == null) {
539	>	if (o == null) {
540		for (int index = 0; index < size; index++)
541	<	if (elementData[index] == null) {
542	<	fastRemove(index);
543	<	return true;
544	<	}
545	<	} else {
546	<	for (int index = 0; index < size; index++)
547	<	if (o.equals(elementData[index])) {
548	<	fastRemove(index);
549	<	return true;
550	<	}
541	>	if (elementData[index] == null) {
542	>	fastRemove(index);
543	>	return true;
544	>	}
545	>	} else {
546	>	for (int index = 0; index < size; index++)
547	>	if (o.equals(elementData[index])) {
548	>	fastRemove(index);
549	>	return true;
550	>	}
551		}
552	<	return false;
552	>	return false;
553		}
554
555		/*
#	Line 464 | Line 562 | public class ArrayList<E> extends Abstra
562		if (numMoved > 0)
563		System.arraycopy(elementData, index+1, elementData, index,
564		numMoved);
565	<	elementData[--size] = null; // Let gc do its work
565	>	elementData[--size] = null; // clear to let GC do its work
566		}
567
568		/**
#	Line 472 | Line 570 | public class ArrayList<E> extends Abstra
570		* be empty after this call returns.
571		*/
572		public void clear() {
573	<	modCount++;
573	>	modCount++;
574
575	<	// Let gc do its work
576	<	for (int i = 0; i < size; i++)
577	<	elementData[i] = null;
575	>	// clear to let GC do its work
576	>	for (int i = 0; i < size; i++)
577	>	elementData[i] = null;
578
579	<	size = 0;
579	>	size = 0;
580		}
581
582		/**
#	Line 491 | Line 589 | public class ArrayList<E> extends Abstra
589		* list is nonempty.)
590		*
591		* @param c collection containing elements to be added to this list
592	<	* @return <tt>true</tt> if this list changed as a result of the call
592	>	* @return {@code true} if this list changed as a result of the call
593		* @throws NullPointerException if the specified collection is null
594		*/
595		public boolean addAll(Collection<? extends E> c) {
596	<	Object[] a = c.toArray();
596	>	Object[] a = c.toArray();
597	>	modCount++;
598		int numNew = a.length;
599	<	ensureCapacity(size + numNew);  // Increments modCount
600	<	System.arraycopy(a, 0, elementData, size, numNew);
601	<	size += numNew;
602	<	return numNew != 0;
599	>	if (numNew == 0)
600	>	return false;
601	>	Object[] elementData;
602	>	final int s;
603	>	if (numNew > (elementData = this.elementData).length - (s = size))
604	>	elementData = grow(s + numNew);
605	>	System.arraycopy(a, 0, elementData, s, numNew);
606	>	size = s + numNew;
607	>	return true;
608		}
609
610		/**
#	Line 514 | Line 618 | public class ArrayList<E> extends Abstra
618		* @param index index at which to insert the first element from the
619		*              specified collection
620		* @param c collection containing elements to be added to this list
621	<	* @return <tt>true</tt> if this list changed as a result of the call
621	>	* @return {@code true} if this list changed as a result of the call
622		* @throws IndexOutOfBoundsException {@inheritDoc}
623		* @throws NullPointerException if the specified collection is null
624		*/
625		public boolean addAll(int index, Collection<? extends E> c) {
626	<	rangeCheckForAdd(index);
626	>	rangeCheckForAdd(index);
627
628	<	Object[] a = c.toArray();
629	<	int numNew = a.length;
630	<	ensureCapacity(size + numNew);  // Increments modCount
631	<
632	<	int numMoved = size - index;
633	<	if (numMoved > 0)
634	<	System.arraycopy(elementData, index, elementData, index + numNew,
635	<	numMoved);
628	>	Object[] a = c.toArray();
629	>	modCount++;
630	>	int numNew = a.length;
631	>	if (numNew == 0)
632	>	return false;
633	>	Object[] elementData;
634	>	final int s;
635	>	if (numNew > (elementData = this.elementData).length - (s = size))
636	>	elementData = grow(s + numNew);
637
638	+	int numMoved = s - index;
639	+	if (numMoved > 0)
640	+	System.arraycopy(elementData, index,
641	+	elementData, index + numNew,
642	+	numMoved);
643		System.arraycopy(a, 0, elementData, index, numNew);
644	<	size += numNew;
645	<	return numNew != 0;
644	>	size = s + numNew;
645	>	return true;
646		}
647
648		/**
#	Line 545 | Line 655 | public class ArrayList<E> extends Abstra
655		* @throws IndexOutOfBoundsException if {@code fromIndex} or
656		*         {@code toIndex} is out of range
657		*         ({@code fromIndex < 0 ||
548	–	*          fromIndex >= size() ||
658		*          toIndex > size() ||
659		*          toIndex < fromIndex})
660		*/
661		protected void removeRange(int fromIndex, int toIndex) {
662	<	modCount++;
663	<	int numMoved = size - toIndex;
662	>	if (fromIndex > toIndex) {
663	>	throw new IndexOutOfBoundsException(
664	>	outOfBoundsMsg(fromIndex, toIndex));
665	>	}
666	>	modCount++;
667	>	int numMoved = size - toIndex;
668		System.arraycopy(elementData, toIndex, elementData, fromIndex,
669		numMoved);
670
671	<	// Let gc do its work
672	<	int newSize = size - (toIndex-fromIndex);
673	<	while (size != newSize)
674	<	elementData[--size] = null;
675	<	}
676	<
564	<	/**
565	<	* Checks if the given index is in range.  If not, throws an appropriate
566	<	* runtime exception.  This method does *not* check if the index is
567	<	* negative: It is always used immediately prior to an array access,
568	<	* which throws an ArrayIndexOutOfBoundsException if index is negative.
569	<	*/
570	<	private void rangeCheck(int index) {
571	<	if (index >= size)
572	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
671	>	// clear to let GC do its work
672	>	int newSize = size - (toIndex-fromIndex);
673	>	for (int i = newSize; i < size; i++) {
674	>	elementData[i] = null;
675	>	}
676	>	size = newSize;
677		}
678
679		/**
680		* A version of rangeCheck used by add and addAll.
681		*/
682		private void rangeCheckForAdd(int index) {
683	<	if (index > size || index < 0)
684	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
683	>	if (index > size || index < 0)
684	>	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
685		}
686
687		/**
#	Line 586 | Line 690 | public class ArrayList<E> extends Abstra
690		* this "outlining" performs best with both server and client VMs.
691		*/
692		private String outOfBoundsMsg(int index) {
693	<	return "Index: "+index+", Size: "+size;
693	>	return "Index: "+index+", Size: "+size;
694	>	}
695	>
696	>	/**
697	>	* A version used in checking (fromIndex > toIndex) condition
698	>	*/
699	>	private static String outOfBoundsMsg(int fromIndex, int toIndex) {
700	>	return "From Index: " + fromIndex + " > To Index: " + toIndex;
701		}
702
703		/**
#	Line 596 | Line 707 | public class ArrayList<E> extends Abstra
707		* @param c collection containing elements to be removed from this list
708		* @return {@code true} if this list changed as a result of the call
709		* @throws ClassCastException if the class of an element of this list
710	<	*         is incompatible with the specified collection (optional)
710	>	*         is incompatible with the specified collection
711	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
712		* @throws NullPointerException if this list contains a null element and the
713	<	*         specified collection does not permit null elements (optional),
713	>	*         specified collection does not permit null elements
714	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
715		*         or if the specified collection is null
716		* @see Collection#contains(Object)
717		*/
718		public boolean removeAll(Collection<?> c) {
719	<	return batchRemove(c, false);
719	>	return batchRemove(c, false);
720		}
721
722		/**
#	Line 614 | Line 727 | public class ArrayList<E> extends Abstra
727		* @param c collection containing elements to be retained in this list
728		* @return {@code true} if this list changed as a result of the call
729		* @throws ClassCastException if the class of an element of this list
730	<	*         is incompatible with the specified collection (optional)
730	>	*         is incompatible with the specified collection
731	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
732		* @throws NullPointerException if this list contains a null element and the
733	<	*         specified collection does not permit null elements (optional),
733	>	*         specified collection does not permit null elements
734	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
735		*         or if the specified collection is null
736		* @see Collection#contains(Object)
737		*/
738		public boolean retainAll(Collection<?> c) {
739	<	return batchRemove(c, true);
739	>	return batchRemove(c, true);
740		}
741
742		private boolean batchRemove(Collection<?> c, boolean complement) {
743	<	final Object[] elementData = this.elementData;
744	<	int r = 0, w = 0;
745	<	boolean modified = false;
746	<	try {
747	<	for (; r < size; r++)
748	<	if (c.contains(elementData[r]) == complement)
749	<	elementData[w++] = elementData[r];
750	<	} finally {
751	<	// Preserve behavioral compatibility with AbstractCollection,
752	<	// even if c.contains() throws.
753	<	if (r != size) {
754	<	System.arraycopy(elementData, r,
755	<	elementData, w,
756	<	size - r);
757	<	w += size - r;
758	<	}
759	<	if (w != size) {
760	<	for (int i = w; i < size; i++)
761	<	elementData[i] = null;
762	<	modCount += size - w;
763	<	size = w;
764	<	modified = true;
765	<	}
766	<	}
767	<	return modified;
743	>	Objects.requireNonNull(c);
744	>	final Object[] es = elementData;
745	>	final int size = this.size;
746	>	final boolean modified;
747	>	int r;
748	>	// Optimize for initial run of survivors
749	>	for (r = 0; r < size && c.contains(es[r]) == complement; r++)
750	>	;
751	>	if (modified = (r < size)) {
752	>	int w = r++;
753	>	try {
754	>	for (Object e; r < size; r++)
755	>	if (c.contains(e = es[r]) == complement)
756	>	es[w++] = e;
757	>	} catch (Throwable ex) {
758	>	// Preserve behavioral compatibility with AbstractCollection,
759	>	// even if c.contains() throws.
760	>	System.arraycopy(es, r, es, w, size - r);
761	>	w += size - r;
762	>	throw ex;
763	>	} finally {
764	>	modCount += size - w;
765	>	Arrays.fill(es, (this.size = w), size, null);
766	>	}
767	>	}
768	>	return modified;
769		}
770
771		/**
772	<	* Save the state of the <tt>ArrayList</tt> instance to a stream (that
772	>	* Save the state of the {@code ArrayList} instance to a stream (that
773		* is, serialize it).
774		*
775	<	* @serialData The length of the array backing the <tt>ArrayList</tt>
775	>	* @serialData The length of the array backing the {@code ArrayList}
776		*             instance is emitted (int), followed by all of its elements
777	<	*             (each an <tt>Object</tt>) in the proper order.
777	>	*             (each an {@code Object}) in the proper order.
778		*/
779		private void writeObject(java.io.ObjectOutputStream s)
780		throws java.io.IOException{
781	<	// Write out element count, and any hidden stuff
782	<	int expectedModCount = modCount;
783	<	s.defaultWriteObject();
781	>	// Write out element count, and any hidden stuff
782	>	int expectedModCount = modCount;
783	>	s.defaultWriteObject();
784
785	<	// Write out array length
786	<	s.writeInt(elementData.length);
785	>	// Write out size as capacity for behavioural compatibility with clone()
786	>	s.writeInt(size);
787
788	<	// Write out all elements in the proper order.
789	<	for (int i=0; i<size; i++)
788	>	// Write out all elements in the proper order.
789	>	for (int i=0; i<size; i++) {
790		s.writeObject(elementData[i]);
791	+	}
792
793	<	if (modCount != expectedModCount) {
793	>	if (modCount != expectedModCount) {
794		throw new ConcurrentModificationException();
795		}
679	–
796		}
797
798		/**
799	<	* Reconstitute the <tt>ArrayList</tt> instance from a stream (that is,
799	>	* Reconstitute the {@code ArrayList} instance from a stream (that is,
800		* deserialize it).
801		*/
802		private void readObject(java.io.ObjectInputStream s)
803		throws java.io.IOException, ClassNotFoundException {
688	–	// Read in size, and any hidden stuff
689	–	s.defaultReadObject();
804
805	<	// Read in array length and allocate array
806	<	int arrayLength = s.readInt();
807	<	Object[] a = elementData = new Object[arrayLength];
808	<
809	<	// Read in all elements in the proper order.
810	<	for (int i=0; i<size; i++)
811	<	a[i] = s.readObject();
805	>	// Read in size, and any hidden stuff
806	>	s.defaultReadObject();
807	>
808	>	// Read in capacity
809	>	s.readInt(); // ignored
810	>
811	>	if (size > 0) {
812	>	// like clone(), allocate array based upon size not capacity
813	>	Object[] elements = new Object[size];
814	>
815	>	// Read in all elements in the proper order.
816	>	for (int i = 0; i < size; i++) {
817	>	elements[i] = s.readObject();
818	>	}
819	>
820	>	elementData = elements;
821	>	} else if (size == 0) {
822	>	elementData = EMPTY_ELEMENTDATA;
823	>	} else {
824	>	throw new java.io.InvalidObjectException("Invalid size: " + size);
825	>	}
826		}
827
828		/**
#	Line 710 | Line 838 | public class ArrayList<E> extends Abstra
838		* @throws IndexOutOfBoundsException {@inheritDoc}
839		*/
840		public ListIterator<E> listIterator(int index) {
841	<	if (index < 0 || index > size)
842	<	throw new IndexOutOfBoundsException("Index: "+index);
715	<	return new ListItr(index);
841	>	rangeCheckForAdd(index);
842	>	return new ListItr(index);
843		}
844
845		/**
#	Line 724 | Line 851 | public class ArrayList<E> extends Abstra
851		* @see #listIterator(int)
852		*/
853		public ListIterator<E> listIterator() {
854	<	return new ListItr(0);
854	>	return new ListItr(0);
855		}
856
857		/**
#	Line 735 | Line 862 | public class ArrayList<E> extends Abstra
862		* @return an iterator over the elements in this list in proper sequence
863		*/
864		public Iterator<E> iterator() {
865	<	return new Itr();
865	>	return new Itr();
866		}
867
868		/**
869		* An optimized version of AbstractList.Itr
870		*/
871		private class Itr implements Iterator<E> {
872	<	int cursor;       // index of next element to return
873	<	int lastRet = -1; // index of last element returned; -1 if no such
874	<	int expectedModCount = modCount;
872	>	int cursor;       // index of next element to return
873	>	int lastRet = -1; // index of last element returned; -1 if no such
874	>	int expectedModCount = modCount;
875	>
876	>	// prevent creating a synthetic constructor
877	>	Itr() {}
878
879	<	public boolean hasNext() {
879	>	public boolean hasNext() {
880		return cursor != size;
881	<	}
881	>	}
882
883	<	@SuppressWarnings("unchecked")
884	<	public E next() {
883	>	@SuppressWarnings("unchecked")
884	>	public E next() {
885		checkForComodification();
886	<	int i = cursor;
887	<	if (i >= size)
888	<	throw new NoSuchElementException();
889	<	Object[] elementData = ArrayList.this.elementData;
890	<	if (i >= elementData.length)
891	<	throw new ConcurrentModificationException();
892	<	cursor = i + 1;
893	<	return (E) elementData[lastRet = i];
894	<	}
895	<
896	<	public void remove() {
897	<	if (lastRet < 0)
898	<	throw new IllegalStateException();
886	>	int i = cursor;
887	>	if (i >= size)
888	>	throw new NoSuchElementException();
889	>	Object[] elementData = ArrayList.this.elementData;
890	>	if (i >= elementData.length)
891	>	throw new ConcurrentModificationException();
892	>	cursor = i + 1;
893	>	return (E) elementData[lastRet = i];
894	>	}
895	>
896	>	public void remove() {
897	>	if (lastRet < 0)
898	>	throw new IllegalStateException();
899		checkForComodification();
900
901	<	try {
902	<	ArrayList.this.remove(lastRet);
903	<	cursor = lastRet;
904	<	lastRet = -1;
905	<	expectedModCount = modCount;
906	<	} catch (IndexOutOfBoundsException ex) {
907	<	throw new ConcurrentModificationException();
908	<	}
909	<	}
910	<
911	<	final void checkForComodification() {
912	<	if (modCount != expectedModCount)
913	<	throw new ConcurrentModificationException();
914	<	}
901	>	try {
902	>	ArrayList.this.remove(lastRet);
903	>	cursor = lastRet;
904	>	lastRet = -1;
905	>	expectedModCount = modCount;
906	>	} catch (IndexOutOfBoundsException ex) {
907	>	throw new ConcurrentModificationException();
908	>	}
909	>	}
910	>
911	>	@Override
912	>	@SuppressWarnings("unchecked")
913	>	public void forEachRemaining(Consumer<? super E> consumer) {
914	>	Objects.requireNonNull(consumer);
915	>	final int size = ArrayList.this.size;
916	>	int i = cursor;
917	>	if (i >= size) {
918	>	return;
919	>	}
920	>	final Object[] elementData = ArrayList.this.elementData;
921	>	if (i >= elementData.length) {
922	>	throw new ConcurrentModificationException();
923	>	}
924	>	while (i != size && modCount == expectedModCount) {
925	>	consumer.accept((E) elementData[i++]);
926	>	}
927	>	// update once at end of iteration to reduce heap write traffic
928	>	cursor = i;
929	>	lastRet = i - 1;
930	>	checkForComodification();
931	>	}
932	>
933	>	final void checkForComodification() {
934	>	if (modCount != expectedModCount)
935	>	throw new ConcurrentModificationException();
936	>	}
937		}
938
939		/**
940		* An optimized version of AbstractList.ListItr
941		*/
942		private class ListItr extends Itr implements ListIterator<E> {
943	<	ListItr(int index) {
944	<	super();
945	<	cursor = index;
946	<	}
947	<
948	<	public boolean hasPrevious() {
949	<	return cursor != 0;
950	<	}
951	<
952	<	public int nextIndex() {
953	<	return cursor;
954	<	}
803	<
804	<	public int previousIndex() {
805	<	return cursor - 1;
806	<	}
943	>	ListItr(int index) {
944	>	super();
945	>	cursor = index;
946	>	}
947	>
948	>	public boolean hasPrevious() {
949	>	return cursor != 0;
950	>	}
951	>
952	>	public int nextIndex() {
953	>	return cursor;
954	>	}
955
956	<	@SuppressWarnings("unchecked")
956	>	public int previousIndex() {
957	>	return cursor - 1;
958	>	}
959	>
960	>	@SuppressWarnings("unchecked")
961		public E previous() {
962	<	checkForComodification();
963	<	int i = cursor - 1;
964	<	if (i < 0)
965	<	throw new NoSuchElementException();
966	<	Object[] elementData = ArrayList.this.elementData;
967	<	if (i >= elementData.length)
968	<	throw new ConcurrentModificationException();
969	<	cursor = i;
970	<	return (E) elementData[lastRet = i];
962	>	checkForComodification();
963	>	int i = cursor - 1;
964	>	if (i < 0)
965	>	throw new NoSuchElementException();
966	>	Object[] elementData = ArrayList.this.elementData;
967	>	if (i >= elementData.length)
968	>	throw new ConcurrentModificationException();
969	>	cursor = i;
970	>	return (E) elementData[lastRet = i];
971		}
972
973	<	public void set(E e) {
974	<	if (lastRet < 0)
975	<	throw new IllegalStateException();
973	>	public void set(E e) {
974	>	if (lastRet < 0)
975	>	throw new IllegalStateException();
976		checkForComodification();
977
978	<	try {
979	<	ArrayList.this.set(lastRet, e);
980	<	} catch (IndexOutOfBoundsException ex) {
981	<	throw new ConcurrentModificationException();
982	<	}
983	<	}
978	>	try {
979	>	ArrayList.this.set(lastRet, e);
980	>	} catch (IndexOutOfBoundsException ex) {
981	>	throw new ConcurrentModificationException();
982	>	}
983	>	}
984
985	<	public void add(E e) {
985	>	public void add(E e) {
986		checkForComodification();
987
988	<	try {
989	<	int i = cursor;
990	<	ArrayList.this.add(i, e);
991	<	cursor = i + 1;
992	<	lastRet = -1;
993	<	expectedModCount = modCount;
994	<	} catch (IndexOutOfBoundsException ex) {
995	<	throw new ConcurrentModificationException();
996	<	}
997	<	}
988	>	try {
989	>	int i = cursor;
990	>	ArrayList.this.add(i, e);
991	>	cursor = i + 1;
992	>	lastRet = -1;
993	>	expectedModCount = modCount;
994	>	} catch (IndexOutOfBoundsException ex) {
995	>	throw new ConcurrentModificationException();
996	>	}
997	>	}
998		}
999
1000		/**
#	Line 875 | Line 1027 | public class ArrayList<E> extends Abstra
1027		* @throws IllegalArgumentException {@inheritDoc}
1028		*/
1029		public List<E> subList(int fromIndex, int toIndex) {
1030	<	subListRangeCheck(fromIndex, toIndex, size);
1031	<	return new SubList(this, 0, fromIndex, toIndex);
1030	>	subListRangeCheck(fromIndex, toIndex, size);
1031	>	return new SubList<>(this, fromIndex, toIndex);
1032		}
1033
1034	<	static void subListRangeCheck(int fromIndex, int toIndex, int size) {
1035	<	if (fromIndex < 0)
1036	<	throw new IndexOutOfBoundsException("fromIndex = " + fromIndex);
1037	<	if (toIndex > size)
1038	<	throw new IndexOutOfBoundsException("toIndex = " + toIndex);
1039	<	if (fromIndex > toIndex)
1040	<	throw new IllegalArgumentException("fromIndex(" + fromIndex +
1041	<	") > toIndex(" + toIndex + ")");
1042	<	}
1043	<
1044	<	private class SubList extends AbstractList<E> implements RandomAccess {
1045	<	private final AbstractList<E> parent;
1046	<	private final int parentOffset;
1047	<	private final int offset;
1048	<	private int size;
1049	<
1050	<	SubList(AbstractList<E> parent,
1051	<	int offset, int fromIndex, int toIndex) {
1052	<	this.parent = parent;
1053	<	this.parentOffset = fromIndex;
1054	<	this.offset = offset + fromIndex;
1055	<	this.size = toIndex - fromIndex;
1056	<	this.modCount = ArrayList.this.modCount;
1057	<	}
1058	<
1059	<	public E set(int index, E e) {
1060	<	rangeCheck(index);
1061	<	checkForComodification();
1062	<	E oldValue = ArrayList.this.elementData(offset + index);
1063	<	ArrayList.this.elementData[offset + index] = e;
1064	<	return oldValue;
1065	<	}
1066	<
1067	<	public E get(int index) {
1068	<	rangeCheck(index);
1069	<	checkForComodification();
1070	<	return ArrayList.this.elementData(offset + index);
1071	<	}
1072	<
1073	<	public int size() {
1074	<	checkForComodification();
1075	<	return this.size;
1076	<	}
1077	<
1078	<	public void add(int index, E e) {
1079	<	rangeCheckForAdd(index);
1080	<	checkForComodification();
1081	<	parent.add(parentOffset + index, e);
1082	<	this.modCount = parent.modCount;
1083	<	this.size++;
1084	<	}
1085	<
1086	<	public E remove(int index) {
1087	<	rangeCheck(index);
1088	<	checkForComodification();
1089	<	E result = parent.remove(parentOffset + index);
1090	<	this.modCount = parent.modCount;
1091	<	this.size--;
1092	<	return result;
1093	<	}
1094	<
1095	<	protected void removeRange(int fromIndex, int toIndex) {
1096	<	checkForComodification();
1097	<	parent.removeRange(parentOffset + fromIndex,
1098	<	parentOffset + toIndex);
1099	<	this.modCount = parent.modCount;
1100	<	this.size -= toIndex - fromIndex;
1101	<	}
1102	<
1103	<	public boolean addAll(Collection<? extends E> c) {
1104	<	return addAll(this.size, c);
1105	<	}
1106	<
1107	<	public boolean addAll(int index, Collection<? extends E> c) {
1108	<	rangeCheckForAdd(index);
1109	<	int cSize = c.size();
1110	<	if (cSize==0)
1111	<	return false;
1112	<
1113	<	checkForComodification();
1114	<	parent.addAll(parentOffset + index, c);
1115	<	this.modCount = parent.modCount;
1116	<	this.size += cSize;
1117	<	return true;
1118	<	}
1119	<
1120	<	public Iterator<E> iterator() {
1121	<	return listIterator();
1122	<	}
1123	<
1124	<	public ListIterator<E> listIterator(final int index) {
1125	<	checkForComodification();
1126	<	rangeCheckForAdd(index);
1127	<
1128	<	return new ListIterator<E>() {
1129	<	int cursor = index;
1130	<	int lastRet = -1;
1131	<	int expectedModCount = ArrayList.this.modCount;
1132	<
1133	<	public boolean hasNext() {
1134	<	return cursor != SubList.this.size;
1135	<	}
1136	<
1137	<	@SuppressWarnings("unchecked")
1138	<	public E next() {
1139	<	checkForComodification();
1140	<	int i = cursor;
1141	<	if (i >= SubList.this.size)
1142	<	throw new NoSuchElementException();
1143	<	Object[] elementData = ArrayList.this.elementData;
1144	<	if (offset + i >= elementData.length)
1145	<	throw new ConcurrentModificationException();
1146	<	cursor = i + 1;
1147	<	return (E) elementData[offset + (lastRet = i)];
1148	<	}
1149	<
1150	<	public boolean hasPrevious() {
1151	<	return cursor != 0;
1152	<	}
1153	<
1154	<	@SuppressWarnings("unchecked")
1155	<	public E previous() {
1156	<	checkForComodification();
1157	<	int i = cursor - 1;
1158	<	if (i < 0)
1159	<	throw new NoSuchElementException();
1160	<	Object[] elementData = ArrayList.this.elementData;
1161	<	if (offset + i >= elementData.length)
1162	<	throw new ConcurrentModificationException();
1163	<	cursor = i;
1164	<	return (E) elementData[offset + (lastRet = i)];
1165	<	}
1166	<
1167	<	public int nextIndex() {
1168	<	return cursor;
1169	<	}
1170	<
1171	<	public int previousIndex() {
1172	<	return cursor - 1;
1173	<	}
1174	<
1175	<	public void remove() {
1176	<	if (lastRet < 0)
1177	<	throw new IllegalStateException();
1178	<	checkForComodification();
1179	<
1180	<	try {
1181	<	SubList.this.remove(lastRet);
1182	<	cursor = lastRet;
1183	<	lastRet = -1;
1184	<	expectedModCount = ArrayList.this.modCount;
1185	<	} catch (IndexOutOfBoundsException ex) {
1186	<	throw new ConcurrentModificationException();
1187	<	}
1188	<	}
1189	<
1190	<	public void set(E e) {
1191	<	if (lastRet < 0)
1192	<	throw new IllegalStateException();
1193	<	checkForComodification();
1194	<
1195	<	try {
1196	<	ArrayList.this.set(offset + lastRet, e);
1197	<	} catch (IndexOutOfBoundsException ex) {
1198	<	throw new ConcurrentModificationException();
1199	<	}
1200	<	}
1201	<
1202	<	public void add(E e) {
1203	<	checkForComodification();
1204	<
1205	<	try {
1206	<	int i = cursor;
1207	<	SubList.this.add(i, e);
1208	<	cursor = i + 1;
1209	<	lastRet = -1;
1210	<	expectedModCount = ArrayList.this.modCount;
1211	<	} catch (IndexOutOfBoundsException ex) {
1212	<	throw new ConcurrentModificationException();
1213	<	}
1214	<	}
1215	<
1216	<	final void checkForComodification() {
1217	<	if (expectedModCount != ArrayList.this.modCount)
1218	<	throw new ConcurrentModificationException();
1219	<	}
1220	<	};
1221	<	}
1222	<
1223	<	public List<E> subList(int fromIndex, int toIndex) {
1224	<	subListRangeCheck(fromIndex, toIndex, size);
1225	<	return new SubList(this, offset, fromIndex, toIndex);
1226	<	}
1227	<
1228	<	private void rangeCheck(int index) {
1229	<	if (index < 0 || index >= this.size)
1230	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
1231	<	}
1232	<
1233	<	private void rangeCheckForAdd(int index) {
1234	<	if (index < 0 || index > this.size)
1235	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
1236	<	}
1237	<
1238	<	private String outOfBoundsMsg(int index) {
1239	<	return "Index: "+index+", Size: "+this.size;
1240	<	}
1241	<
1242	<	private void checkForComodification() {
1243	<	if (ArrayList.this.modCount != this.modCount)
1244	<	throw new ConcurrentModificationException();
1245	<	}
1034	>	private static class SubList<E> extends AbstractList<E> implements RandomAccess {
1035	>	private final ArrayList<E> root;
1036	>	private final SubList<E> parent;
1037	>	private final int offset;
1038	>	private int size;
1039	>
1040	>	/**
1041	>	* Constructs a sublist of an arbitrary ArrayList.
1042	>	*/
1043	>	public SubList(ArrayList<E> root, int fromIndex, int toIndex) {
1044	>	this.root = root;
1045	>	this.parent = null;
1046	>	this.offset = fromIndex;
1047	>	this.size = toIndex - fromIndex;
1048	>	this.modCount = root.modCount;
1049	>	}
1050	>
1051	>	/**
1052	>	* Constructs a sublist of another SubList.
1053	>	*/
1054	>	private SubList(SubList<E> parent, int fromIndex, int toIndex) {
1055	>	this.root = parent.root;
1056	>	this.parent = parent;
1057	>	this.offset = parent.offset + fromIndex;
1058	>	this.size = toIndex - fromIndex;
1059	>	this.modCount = root.modCount;
1060	>	}
1061	>
1062	>	public E set(int index, E element) {
1063	>	Objects.checkIndex(index, size);
1064	>	checkForComodification();
1065	>	E oldValue = root.elementData(offset + index);
1066	>	root.elementData[offset + index] = element;
1067	>	return oldValue;
1068	>	}
1069	>
1070	>	public E get(int index) {
1071	>	Objects.checkIndex(index, size);
1072	>	checkForComodification();
1073	>	return root.elementData(offset + index);
1074	>	}
1075	>
1076	>	public int size() {
1077	>	checkForComodification();
1078	>	return size;
1079	>	}
1080	>
1081	>	public void add(int index, E element) {
1082	>	rangeCheckForAdd(index);
1083	>	checkForComodification();
1084	>	root.add(offset + index, element);
1085	>	updateSizeAndModCount(1);
1086	>	}
1087	>
1088	>	public E remove(int index) {
1089	>	Objects.checkIndex(index, size);
1090	>	checkForComodification();
1091	>	E result = root.remove(offset + index);
1092	>	updateSizeAndModCount(-1);
1093	>	return result;
1094	>	}
1095	>
1096	>	protected void removeRange(int fromIndex, int toIndex) {
1097	>	checkForComodification();
1098	>	root.removeRange(offset + fromIndex, offset + toIndex);
1099	>	updateSizeAndModCount(fromIndex - toIndex);
1100	>	}
1101	>
1102	>	public boolean addAll(Collection<? extends E> c) {
1103	>	return addAll(this.size, c);
1104	>	}
1105	>
1106	>	public boolean addAll(int index, Collection<? extends E> c) {
1107	>	rangeCheckForAdd(index);
1108	>	int cSize = c.size();
1109	>	if (cSize==0)
1110	>	return false;
1111	>	checkForComodification();
1112	>	root.addAll(offset + index, c);
1113	>	updateSizeAndModCount(cSize);
1114	>	return true;
1115	>	}
1116	>
1117	>	public Iterator<E> iterator() {
1118	>	return listIterator();
1119	>	}
1120	>
1121	>	public ListIterator<E> listIterator(int index) {
1122	>	checkForComodification();
1123	>	rangeCheckForAdd(index);
1124	>
1125	>	return new ListIterator<E>() {
1126	>	int cursor = index;
1127	>	int lastRet = -1;
1128	>	int expectedModCount = root.modCount;
1129	>
1130	>	public boolean hasNext() {
1131	>	return cursor != SubList.this.size;
1132	>	}
1133	>
1134	>	@SuppressWarnings("unchecked")
1135	>	public E next() {
1136	>	checkForComodification();
1137	>	int i = cursor;
1138	>	if (i >= SubList.this.size)
1139	>	throw new NoSuchElementException();
1140	>	Object[] elementData = root.elementData;
1141	>	if (offset + i >= elementData.length)
1142	>	throw new ConcurrentModificationException();
1143	>	cursor = i + 1;
1144	>	return (E) elementData[offset + (lastRet = i)];
1145	>	}
1146	>
1147	>	public boolean hasPrevious() {
1148	>	return cursor != 0;
1149	>	}
1150	>
1151	>	@SuppressWarnings("unchecked")
1152	>	public E previous() {
1153	>	checkForComodification();
1154	>	int i = cursor - 1;
1155	>	if (i < 0)
1156	>	throw new NoSuchElementException();
1157	>	Object[] elementData = root.elementData;
1158	>	if (offset + i >= elementData.length)
1159	>	throw new ConcurrentModificationException();
1160	>	cursor = i;
1161	>	return (E) elementData[offset + (lastRet = i)];
1162	>	}
1163	>
1164	>	@SuppressWarnings("unchecked")
1165	>	public void forEachRemaining(Consumer<? super E> consumer) {
1166	>	Objects.requireNonNull(consumer);
1167	>	final int size = SubList.this.size;
1168	>	int i = cursor;
1169	>	if (i >= size) {
1170	>	return;
1171	>	}
1172	>	final Object[] elementData = root.elementData;
1173	>	if (offset + i >= elementData.length) {
1174	>	throw new ConcurrentModificationException();
1175	>	}
1176	>	while (i != size && modCount == expectedModCount) {
1177	>	consumer.accept((E) elementData[offset + (i++)]);
1178	>	}
1179	>	// update once at end of iteration to reduce heap write traffic
1180	>	lastRet = cursor = i;
1181	>	checkForComodification();
1182	>	}
1183	>
1184	>	public int nextIndex() {
1185	>	return cursor;
1186	>	}
1187	>
1188	>	public int previousIndex() {
1189	>	return cursor - 1;
1190	>	}
1191	>
1192	>	public void remove() {
1193	>	if (lastRet < 0)
1194	>	throw new IllegalStateException();
1195	>	checkForComodification();
1196	>
1197	>	try {
1198	>	SubList.this.remove(lastRet);
1199	>	cursor = lastRet;
1200	>	lastRet = -1;
1201	>	expectedModCount = root.modCount;
1202	>	} catch (IndexOutOfBoundsException ex) {
1203	>	throw new ConcurrentModificationException();
1204	>	}
1205	>	}
1206	>
1207	>	public void set(E e) {
1208	>	if (lastRet < 0)
1209	>	throw new IllegalStateException();
1210	>	checkForComodification();
1211	>
1212	>	try {
1213	>	root.set(offset + lastRet, e);
1214	>	} catch (IndexOutOfBoundsException ex) {
1215	>	throw new ConcurrentModificationException();
1216	>	}
1217	>	}
1218	>
1219	>	public void add(E e) {
1220	>	checkForComodification();
1221	>
1222	>	try {
1223	>	int i = cursor;
1224	>	SubList.this.add(i, e);
1225	>	cursor = i + 1;
1226	>	lastRet = -1;
1227	>	expectedModCount = root.modCount;
1228	>	} catch (IndexOutOfBoundsException ex) {
1229	>	throw new ConcurrentModificationException();
1230	>	}
1231	>	}
1232	>
1233	>	final void checkForComodification() {
1234	>	if (root.modCount != expectedModCount)
1235	>	throw new ConcurrentModificationException();
1236	>	}
1237	>	};
1238	>	}
1239	>
1240	>	public List<E> subList(int fromIndex, int toIndex) {
1241	>	subListRangeCheck(fromIndex, toIndex, size);
1242	>	return new SubList<>(this, fromIndex, toIndex);
1243	>	}
1244	>
1245	>	private void rangeCheckForAdd(int index) {
1246	>	if (index < 0 || index > this.size)
1247	>	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
1248	>	}
1249	>
1250	>	private String outOfBoundsMsg(int index) {
1251	>	return "Index: "+index+", Size: "+this.size;
1252	>	}
1253	>
1254	>	private void checkForComodification() {
1255	>	if (root.modCount != modCount)
1256	>	throw new ConcurrentModificationException();
1257	>	}
1258	>
1259	>	private void updateSizeAndModCount(int sizeChange) {
1260	>	SubList<E> slist = this;
1261	>	do {
1262	>	slist.size += sizeChange;
1263	>	slist.modCount = root.modCount;
1264	>	slist = slist.parent;
1265	>	} while (slist != null);
1266	>	}
1267	>
1268	>	public Spliterator<E> spliterator() {
1269	>	checkForComodification();
1270	>
1271	>	// ArrayListSpliterator is not used because late-binding logic
1272	>	// is different here
1273	>	return new Spliterator<>() {
1274	>	private int index = offset; // current index, modified on advance/split
1275	>	private int fence = -1; // -1 until used; then one past last index
1276	>	private int expectedModCount; // initialized when fence set
1277	>
1278	>	private int getFence() { // initialize fence to size on first use
1279	>	int hi; // (a specialized variant appears in method forEach)
1280	>	if ((hi = fence) < 0) {
1281	>	expectedModCount = modCount;
1282	>	hi = fence = offset + size;
1283	>	}
1284	>	return hi;
1285	>	}
1286	>
1287	>	public ArrayListSpliterator<E> trySplit() {
1288	>	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1289	>	// ArrayListSpliterator could be used here as the source is already bound
1290	>	return (lo >= mid) ? null : // divide range in half unless too small
1291	>	new ArrayListSpliterator<>(root, lo, index = mid,
1292	>	expectedModCount);
1293	>	}
1294	>
1295	>	public boolean tryAdvance(Consumer<? super E> action) {
1296	>	Objects.requireNonNull(action);
1297	>	int hi = getFence(), i = index;
1298	>	if (i < hi) {
1299	>	index = i + 1;
1300	>	@SuppressWarnings("unchecked") E e = (E)root.elementData[i];
1301	>	action.accept(e);
1302	>	if (root.modCount != expectedModCount)
1303	>	throw new ConcurrentModificationException();
1304	>	return true;
1305	>	}
1306	>	return false;
1307	>	}
1308	>
1309	>	public void forEachRemaining(Consumer<? super E> action) {
1310	>	Objects.requireNonNull(action);
1311	>	int i, hi, mc; // hoist accesses and checks from loop
1312	>	ArrayList<E> lst = root;
1313	>	Object[] a;
1314	>	if ((a = lst.elementData) != null) {
1315	>	if ((hi = fence) < 0) {
1316	>	mc = modCount;
1317	>	hi = offset + size;
1318	>	}
1319	>	else
1320	>	mc = expectedModCount;
1321	>	if ((i = index) >= 0 && (index = hi) <= a.length) {
1322	>	for (; i < hi; ++i) {
1323	>	@SuppressWarnings("unchecked") E e = (E) a[i];
1324	>	action.accept(e);
1325	>	}
1326	>	if (lst.modCount == mc)
1327	>	return;
1328	>	}
1329	>	}
1330	>	throw new ConcurrentModificationException();
1331	>	}
1332	>
1333	>	public long estimateSize() {
1334	>	return (long) (getFence() - index);
1335	>	}
1336	>
1337	>	public int characteristics() {
1338	>	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1339	>	}
1340	>	};
1341	>	}
1342	>	}
1343	>
1344	>	@Override
1345	>	public void forEach(Consumer<? super E> action) {
1346	>	Objects.requireNonNull(action);
1347	>	final int expectedModCount = modCount;
1348	>	@SuppressWarnings("unchecked")
1349	>	final E[] elementData = (E[]) this.elementData;
1350	>	final int size = this.size;
1351	>	for (int i=0; modCount == expectedModCount && i < size; i++) {
1352	>	action.accept(elementData[i]);
1353	>	}
1354	>	if (modCount != expectedModCount) {
1355	>	throw new ConcurrentModificationException();
1356	>	}
1357	>	}
1358	>
1359	>	/**
1360	>	* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
1361	>	* and <em>fail-fast</em> {@link Spliterator} over the elements in this
1362	>	* list.
1363	>	*
1364	>	* <p>The {@code Spliterator} reports {@link Spliterator#SIZED},
1365	>	* {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}.
1366	>	* Overriding implementations should document the reporting of additional
1367	>	* characteristic values.
1368	>	*
1369	>	* @return a {@code Spliterator} over the elements in this list
1370	>	* @since 1.8
1371	>	*/
1372	>	@Override
1373	>	public Spliterator<E> spliterator() {
1374	>	return new ArrayListSpliterator<>(this, 0, -1, 0);
1375	>	}
1376	>
1377	>	/** Index-based split-by-two, lazily initialized Spliterator */
1378	>	static final class ArrayListSpliterator<E> implements Spliterator<E> {
1379	>
1380	>	/*
1381	>	* If ArrayLists were immutable, or structurally immutable (no
1382	>	* adds, removes, etc), we could implement their spliterators
1383	>	* with Arrays.spliterator. Instead we detect as much
1384	>	* interference during traversal as practical without
1385	>	* sacrificing much performance. We rely primarily on
1386	>	* modCounts. These are not guaranteed to detect concurrency
1387	>	* violations, and are sometimes overly conservative about
1388	>	* within-thread interference, but detect enough problems to
1389	>	* be worthwhile in practice. To carry this out, we (1) lazily
1390	>	* initialize fence and expectedModCount until the latest
1391	>	* point that we need to commit to the state we are checking
1392	>	* against; thus improving precision.  (This doesn't apply to
1393	>	* SubLists, that create spliterators with current non-lazy
1394	>	* values).  (2) We perform only a single
1395	>	* ConcurrentModificationException check at the end of forEach
1396	>	* (the most performance-sensitive method). When using forEach
1397	>	* (as opposed to iterators), we can normally only detect
1398	>	* interference after actions, not before. Further
1399	>	* CME-triggering checks apply to all other possible
1400	>	* violations of assumptions for example null or too-small
1401	>	* elementData array given its size(), that could only have
1402	>	* occurred due to interference.  This allows the inner loop
1403	>	* of forEach to run without any further checks, and
1404	>	* simplifies lambda-resolution. While this does entail a
1405	>	* number of checks, note that in the common case of
1406	>	* list.stream().forEach(a), no checks or other computation
1407	>	* occur anywhere other than inside forEach itself.  The other
1408	>	* less-often-used methods cannot take advantage of most of
1409	>	* these streamlinings.
1410	>	*/
1411	>
1412	>	private final ArrayList<E> list;
1413	>	private int index; // current index, modified on advance/split
1414	>	private int fence; // -1 until used; then one past last index
1415	>	private int expectedModCount; // initialized when fence set
1416	>
1417	>	/** Create new spliterator covering the given  range */
1418	>	ArrayListSpliterator(ArrayList<E> list, int origin, int fence,
1419	>	int expectedModCount) {
1420	>	this.list = list; // OK if null unless traversed
1421	>	this.index = origin;
1422	>	this.fence = fence;
1423	>	this.expectedModCount = expectedModCount;
1424	>	}
1425	>
1426	>	private int getFence() { // initialize fence to size on first use
1427	>	int hi; // (a specialized variant appears in method forEach)
1428	>	ArrayList<E> lst;
1429	>	if ((hi = fence) < 0) {
1430	>	if ((lst = list) == null)
1431	>	hi = fence = 0;
1432	>	else {
1433	>	expectedModCount = lst.modCount;
1434	>	hi = fence = lst.size;
1435	>	}
1436	>	}
1437	>	return hi;
1438	>	}
1439	>
1440	>	public ArrayListSpliterator<E> trySplit() {
1441	>	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1442	>	return (lo >= mid) ? null : // divide range in half unless too small
1443	>	new ArrayListSpliterator<>(list, lo, index = mid,
1444	>	expectedModCount);
1445	>	}
1446	>
1447	>	public boolean tryAdvance(Consumer<? super E> action) {
1448	>	if (action == null)
1449	>	throw new NullPointerException();
1450	>	int hi = getFence(), i = index;
1451	>	if (i < hi) {
1452	>	index = i + 1;
1453	>	@SuppressWarnings("unchecked") E e = (E)list.elementData[i];
1454	>	action.accept(e);
1455	>	if (list.modCount != expectedModCount)
1456	>	throw new ConcurrentModificationException();
1457	>	return true;
1458	>	}
1459	>	return false;
1460	>	}
1461	>
1462	>	public void forEachRemaining(Consumer<? super E> action) {
1463	>	int i, hi, mc; // hoist accesses and checks from loop
1464	>	ArrayList<E> lst; Object[] a;
1465	>	if (action == null)
1466	>	throw new NullPointerException();
1467	>	if ((lst = list) != null && (a = lst.elementData) != null) {
1468	>	if ((hi = fence) < 0) {
1469	>	mc = lst.modCount;
1470	>	hi = lst.size;
1471	>	}
1472	>	else
1473	>	mc = expectedModCount;
1474	>	if ((i = index) >= 0 && (index = hi) <= a.length) {
1475	>	for (; i < hi; ++i) {
1476	>	@SuppressWarnings("unchecked") E e = (E) a[i];
1477	>	action.accept(e);
1478	>	}
1479	>	if (lst.modCount == mc)
1480	>	return;
1481	>	}
1482	>	}
1483	>	throw new ConcurrentModificationException();
1484	>	}
1485	>
1486	>	public long estimateSize() {
1487	>	return (long) (getFence() - index);
1488	>	}
1489	>
1490	>	public int characteristics() {
1491	>	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1492	>	}
1493	>	}
1494	>
1495	>	@SuppressWarnings("unchecked")
1496	>	@Override
1497	>	public boolean removeIf(Predicate<? super E> filter) {
1498	>	Objects.requireNonNull(filter);
1499	>	int expectedModCount = modCount;
1500	>	final Object[] es = elementData;
1501	>	final int size = this.size;
1502	>	final boolean modified;
1503	>	int r;
1504	>	// Optimize for initial run of survivors
1505	>	for (r = 0; r < size && !filter.test((E) es[r]); r++)
1506	>	;
1507	>	if (modified = (r < size)) {
1508	>	expectedModCount++;
1509	>	modCount++;
1510	>	int w = r++;
1511	>	try {
1512	>	for (E e; r < size; r++)
1513	>	if (!filter.test(e = (E) es[r]))
1514	>	es[w++] = e;
1515	>	} catch (Throwable ex) {
1516	>	// copy remaining elements
1517	>	System.arraycopy(es, r, es, w, size - r);
1518	>	w += size - r;
1519	>	throw ex;
1520	>	} finally {
1521	>	Arrays.fill(es, (this.size = w), size, null);
1522	>	}
1523	>	}
1524	>	if (modCount != expectedModCount)
1525	>	throw new ConcurrentModificationException();
1526	>	return modified;
1527	>	}
1528	>
1529	>	@Override
1530	>	@SuppressWarnings("unchecked")
1531	>	public void replaceAll(UnaryOperator<E> operator) {
1532	>	Objects.requireNonNull(operator);
1533	>	final int expectedModCount = modCount;
1534	>	final int size = this.size;
1535	>	for (int i=0; modCount == expectedModCount && i < size; i++) {
1536	>	elementData[i] = operator.apply((E) elementData[i]);
1537	>	}
1538	>	if (modCount != expectedModCount) {
1539	>	throw new ConcurrentModificationException();
1540	>	}
1541	>	modCount++;
1542	>	}
1543	>
1544	>	@Override
1545	>	@SuppressWarnings("unchecked")
1546	>	public void sort(Comparator<? super E> c) {
1547	>	final int expectedModCount = modCount;
1548	>	Arrays.sort((E[]) elementData, 0, size, c);
1549	>	if (modCount != expectedModCount) {
1550	>	throw new ConcurrentModificationException();
1551	>	}
1552	>	modCount++;
1553		}
1554		}

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