ViewVC Help

View File | Revision Log | Show Annotations | Download File | Root Listing

root/jsr166/jsr166/src/main/java/util/ArrayList.java

Comparing jsr166/src/main/java/util/ArrayList.java (file contents):
Revision 1.29 by jsr166, Tue Jul 21 23:56:46 2009 UTC vs.
Revision 1.68 by jsr166, Sat Aug 10 16:48:05 2019 UTC

#	Line 1 | Line 1
1		/*
2	<	* Copyright 1997-2008 Sun Microsystems, Inc.  All Rights Reserved.
2	>	* Copyright (c) 1997, 2019, 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	+	// OPENJDK import jdk.internal.access.SharedSecrets;
32	+	import jdk.internal.util.ArraysSupport;
33	+
34		/**
35	<	* Resizable-array implementation of the <tt>List</tt> interface.  Implements
35	>	* Resizable-array implementation of the {@code List} interface.  Implements
36		* all optional list operations, and permits all elements, including
37	<	* <tt>null</tt>.  In addition to implementing the <tt>List</tt> interface,
37	>	* {@code null}.  In addition to implementing the {@code List} interface,
38		* this class provides methods to manipulate the size of the array that is
39		* used internally to store the list.  (This class is roughly equivalent to
40	<	* <tt>Vector</tt>, except that it is unsynchronized.)
40	>	* {@code Vector}, except that it is unsynchronized.)
41		*
42	<	* <p>The <tt>size</tt>, <tt>isEmpty</tt>, <tt>get</tt>, <tt>set</tt>,
43	<	* <tt>iterator</tt>, and <tt>listIterator</tt> operations run in constant
44	<	* time.  The <tt>add</tt> operation runs in <i>amortized constant time</i>,
42	>	* <p>The {@code size}, {@code isEmpty}, {@code get}, {@code set},
43	>	* {@code iterator}, and {@code listIterator} operations run in constant
44	>	* time.  The {@code add} operation runs in <i>amortized constant time</i>,
45		* that is, adding n elements requires O(n) time.  All of the other operations
46		* run in linear time (roughly speaking).  The constant factor is low compared
47	<	* to that for the <tt>LinkedList</tt> implementation.
47	>	* to that for the {@code LinkedList} implementation.
48		*
49	<	* <p>Each <tt>ArrayList</tt> instance has a <i>capacity</i>.  The capacity is
49	>	* <p>Each {@code ArrayList} instance has a <i>capacity</i>.  The capacity is
50		* the size of the array used to store the elements in the list.  It is always
51		* at least as large as the list size.  As elements are added to an ArrayList,
52		* its capacity grows automatically.  The details of the growth policy are not
53		* specified beyond the fact that adding an element has constant amortized
54		* time cost.
55		*
56	<	* <p>An application can increase the capacity of an <tt>ArrayList</tt> instance
57	<	* before adding a large number of elements using the <tt>ensureCapacity</tt>
56	>	* <p>An application can increase the capacity of an {@code ArrayList} instance
57	>	* before adding a large number of elements using the {@code ensureCapacity}
58		* operation.  This may reduce the amount of incremental reallocation.
59		*
60		* <p><strong>Note that this implementation is not synchronized.</strong>
61	<	* If multiple threads access an <tt>ArrayList</tt> instance concurrently,
61	>	* If multiple threads access an {@code ArrayList} instance concurrently,
62		* and at least one of the threads modifies the list structurally, it
63		* <i>must</i> be synchronized externally.  (A structural modification is
64		* any operation that adds or deletes one or more elements, or explicitly
#	Line 66 | Line 72 | package java.util;
72		* unsynchronized access to the list:<pre>
73		*   List list = Collections.synchronizedList(new ArrayList(...));</pre>
74		*
75	<	* <p><a name="fail-fast"/>
75	>	* <p id="fail-fast">
76		* The iterators returned by this class's {@link #iterator() iterator} and
77		* {@link #listIterator(int) listIterator} methods are <em>fail-fast</em>:
78		* if the list is structurally modified at any time after the iterator is
#	Line 87 | Line 93 | package java.util;
93		* should be used only to detect bugs.</i>
94		*
95		* <p>This class is a member of the
96	<	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
96	>	* <a href="{@docRoot}/java.base/java/util/package-summary.html#CollectionsFramework">
97		* Java Collections Framework</a>.
98		*
99	+	* @param <E> the type of elements in this list
100	+	*
101		* @author  Josh Bloch
102		* @author  Neal Gafter
103		* @see     Collection
#	Line 98 | Line 106 | package java.util;
106		* @see     Vector
107		* @since   1.2
108		*/
101	–
109		public class ArrayList<E> extends AbstractList<E>
110		implements List<E>, RandomAccess, Cloneable, java.io.Serializable
111		{
112		private static final long serialVersionUID = 8683452581122892189L;
113
114		/**
115	+	* Default initial capacity.
116	+	*/
117	+	private static final int DEFAULT_CAPACITY = 10;
118	+
119	+	/**
120	+	* Shared empty array instance used for empty instances.
121	+	*/
122	+	private static final Object[] EMPTY_ELEMENTDATA = {};
123	+
124	+	/**
125	+	* Shared empty array instance used for default sized empty instances. We
126	+	* distinguish this from EMPTY_ELEMENTDATA to know how much to inflate when
127	+	* first element is added.
128	+	*/
129	+	private static final Object[] DEFAULTCAPACITY_EMPTY_ELEMENTDATA = {};
130	+
131	+	/**
132		* The array buffer into which the elements of the ArrayList are stored.
133	<	* The capacity of the ArrayList is the length of this array buffer.
133	>	* The capacity of the ArrayList is the length of this array buffer. Any
134	>	* empty ArrayList with elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
135	>	* will be expanded to DEFAULT_CAPACITY when the first element is added.
136		*/
137	<	private transient Object[] elementData;
137	>	transient Object[] elementData; // non-private to simplify nested class access
138
139		/**
140		* The size of the ArrayList (the number of elements it contains).
#	Line 120 | Line 146 | public class ArrayList<E> extends Abstra
146		/**
147		* Constructs an empty list with the specified initial capacity.
148		*
149	<	* @param   initialCapacity   the initial capacity of the list
150	<	* @exception IllegalArgumentException if the specified initial capacity
151	<	*            is negative
149	>	* @param  initialCapacity  the initial capacity of the list
150	>	* @throws IllegalArgumentException if the specified initial capacity
151	>	*         is negative
152		*/
153		public ArrayList(int initialCapacity) {
154	<	super();
155	<	if (initialCapacity < 0)
154	>	if (initialCapacity > 0) {
155	>	this.elementData = new Object[initialCapacity];
156	>	} else if (initialCapacity == 0) {
157	>	this.elementData = EMPTY_ELEMENTDATA;
158	>	} else {
159		throw new IllegalArgumentException("Illegal Capacity: "+
160		initialCapacity);
161	<	this.elementData = new Object[initialCapacity];
161	>	}
162		}
163
164		/**
165		* Constructs an empty list with an initial capacity of ten.
166		*/
167		public ArrayList() {
168	<	this(10);
168	>	this.elementData = DEFAULTCAPACITY_EMPTY_ELEMENTDATA;
169		}
170
171		/**
#	Line 149 | Line 178 | public class ArrayList<E> extends Abstra
178		*/
179		public ArrayList(Collection<? extends E> c) {
180		elementData = c.toArray();
181	<	size = elementData.length;
182	<	// c.toArray might (incorrectly) not return Object[] (see 6260652)
183	<	if (elementData.getClass() != Object[].class)
184	<	elementData = Arrays.copyOf(elementData, size, Object[].class);
181	>	if ((size = elementData.length) != 0) {
182	>	// defend against c.toArray (incorrectly) not returning Object[]
183	>	// (see e.g. https://bugs.openjdk.java.net/browse/JDK-6260652)
184	>	if (elementData.getClass() != Object[].class)
185	>	elementData = Arrays.copyOf(elementData, size, Object[].class);
186	>	} else {
187	>	// replace with empty array.
188	>	this.elementData = EMPTY_ELEMENTDATA;
189	>	}
190		}
191
192		/**
193	<	* Trims the capacity of this <tt>ArrayList</tt> instance to be the
193	>	* Trims the capacity of this {@code ArrayList} instance to be the
194		* list's current size.  An application can use this operation to minimize
195	<	* the storage of an <tt>ArrayList</tt> instance.
195	>	* the storage of an {@code ArrayList} instance.
196		*/
197		public void trimToSize() {
198		modCount++;
199	<	int oldCapacity = elementData.length;
200	<	if (size < oldCapacity) {
201	<	elementData = Arrays.copyOf(elementData, size);
199	>	if (size < elementData.length) {
200	>	elementData = (size == 0)
201	>	? EMPTY_ELEMENTDATA
202	>	: Arrays.copyOf(elementData, size);
203		}
204		}
205
206		/**
207	<	* Increases the capacity of this <tt>ArrayList</tt> instance, if
207	>	* Increases the capacity of this {@code ArrayList} instance, if
208		* necessary, to ensure that it can hold at least the number of elements
209		* specified by the minimum capacity argument.
210		*
211	<	* @param   minCapacity   the desired minimum capacity
211	>	* @param minCapacity the desired minimum capacity
212		*/
213		public void ensureCapacity(int minCapacity) {
214	<	modCount++;
214	>	if (minCapacity > elementData.length
215	>	&& !(elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
216	>	&& minCapacity <= DEFAULT_CAPACITY)) {
217	>	modCount++;
218	>	grow(minCapacity);
219	>	}
220	>	}
221	>
222	>	/**
223	>	* Increases the capacity to ensure that it can hold at least the
224	>	* number of elements specified by the minimum capacity argument.
225	>	*
226	>	* @param minCapacity the desired minimum capacity
227	>	* @throws OutOfMemoryError if minCapacity is less than zero
228	>	*/
229	>	private Object[] grow(int minCapacity) {
230		int oldCapacity = elementData.length;
231	<	if (minCapacity > oldCapacity) {
232	<	int newCapacity = (oldCapacity * 3)/2 + 1;
233	<	if (newCapacity < minCapacity)
234	<	newCapacity = minCapacity;
235	<	// minCapacity is usually close to size, so this is a win:
236	<	elementData = Arrays.copyOf(elementData, newCapacity);
231	>	if (oldCapacity > 0 || elementData != DEFAULTCAPACITY_EMPTY_ELEMENTDATA) {
232	>	int newCapacity = ArraysSupport.newLength(oldCapacity,
233	>	minCapacity - oldCapacity, /* minimum growth */
234	>	oldCapacity >> 1           /* preferred growth */);
235	>	return elementData = Arrays.copyOf(elementData, newCapacity);
236	>	} else {
237	>	return elementData = new Object[Math.max(DEFAULT_CAPACITY, minCapacity)];
238		}
239		}
240
241	+	private Object[] grow() {
242	+	return grow(size + 1);
243	+	}
244	+
245		/**
246		* Returns the number of elements in this list.
247		*
#	Line 197 | Line 252 | public class ArrayList<E> extends Abstra
252		}
253
254		/**
255	<	* Returns <tt>true</tt> if this list contains no elements.
255	>	* Returns {@code true} if this list contains no elements.
256		*
257	<	* @return <tt>true</tt> if this list contains no elements
257	>	* @return {@code true} if this list contains no elements
258		*/
259		public boolean isEmpty() {
260		return size == 0;
261		}
262
263		/**
264	<	* Returns <tt>true</tt> if this list contains the specified element.
265	<	* More formally, returns <tt>true</tt> if and only if this list contains
266	<	* at least one element <tt>e</tt> such that
267	<	* <tt>(o==null&nbsp;?&nbsp;e==null&nbsp;:&nbsp;o.equals(e))</tt>.
264	>	* Returns {@code true} if this list contains the specified element.
265	>	* More formally, returns {@code true} if and only if this list contains
266	>	* at least one element {@code e} such that
267	>	* {@code Objects.equals(o, e)}.
268		*
269		* @param o element whose presence in this list is to be tested
270	<	* @return <tt>true</tt> if this list contains the specified element
270	>	* @return {@code true} if this list contains the specified element
271		*/
272		public boolean contains(Object o) {
273		return indexOf(o) >= 0;
#	Line 221 | Line 276 | public class ArrayList<E> extends Abstra
276		/**
277		* Returns the index of the first occurrence of the specified element
278		* in this list, or -1 if this list does not contain the element.
279	<	* More formally, returns the lowest index <tt>i</tt> such that
280	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
279	>	* More formally, returns the lowest index {@code i} such that
280	>	* {@code Objects.equals(o, get(i))},
281		* or -1 if there is no such index.
282		*/
283		public int indexOf(Object o) {
284	+	return indexOfRange(o, 0, size);
285	+	}
286	+
287	+	int indexOfRange(Object o, int start, int end) {
288	+	Object[] es = elementData;
289		if (o == null) {
290	<	for (int i = 0; i < size; i++)
291	<	if (elementData[i]==null)
290	>	for (int i = start; i < end; i++) {
291	>	if (es[i] == null) {
292		return i;
293	+	}
294	+	}
295		} else {
296	<	for (int i = 0; i < size; i++)
297	<	if (o.equals(elementData[i]))
296	>	for (int i = start; i < end; i++) {
297	>	if (o.equals(es[i])) {
298		return i;
299	+	}
300	+	}
301		}
302		return -1;
303		}
#	Line 241 | Line 305 | public class ArrayList<E> extends Abstra
305		/**
306		* Returns the index of the last occurrence of the specified element
307		* in this list, or -1 if this list does not contain the element.
308	<	* More formally, returns the highest index <tt>i</tt> such that
309	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
308	>	* More formally, returns the highest index {@code i} such that
309	>	* {@code Objects.equals(o, get(i))},
310		* or -1 if there is no such index.
311		*/
312		public int lastIndexOf(Object o) {
313	+	return lastIndexOfRange(o, 0, size);
314	+	}
315	+
316	+	int lastIndexOfRange(Object o, int start, int end) {
317	+	Object[] es = elementData;
318		if (o == null) {
319	<	for (int i = size-1; i >= 0; i--)
320	<	if (elementData[i]==null)
319	>	for (int i = end - 1; i >= start; i--) {
320	>	if (es[i] == null) {
321		return i;
322	+	}
323	+	}
324		} else {
325	<	for (int i = size-1; i >= 0; i--)
326	<	if (o.equals(elementData[i]))
325	>	for (int i = end - 1; i >= start; i--) {
326	>	if (o.equals(es[i])) {
327		return i;
328	+	}
329	+	}
330		}
331		return -1;
332		}
333
334		/**
335	<	* Returns a shallow copy of this <tt>ArrayList</tt> instance.  (The
335	>	* Returns a shallow copy of this {@code ArrayList} instance.  (The
336		* elements themselves are not copied.)
337		*
338	<	* @return a clone of this <tt>ArrayList</tt> instance
338	>	* @return a clone of this {@code ArrayList} instance
339		*/
340		public Object clone() {
341		try {
342	<	@SuppressWarnings("unchecked")
270	<	ArrayList<E> v = (ArrayList<E>) super.clone();
342	>	ArrayList<?> v = (ArrayList<?>) super.clone();
343		v.elementData = Arrays.copyOf(elementData, size);
344		v.modCount = 0;
345		return v;
346		} catch (CloneNotSupportedException e) {
347		// this shouldn't happen, since we are Cloneable
348	<	throw new InternalError();
348	>	throw new InternalError(e);
349		}
350		}
351
#	Line 306 | Line 378 | public class ArrayList<E> extends Abstra
378		* <p>If the list fits in the specified array with room to spare
379		* (i.e., the array has more elements than the list), the element in
380		* the array immediately following the end of the collection is set to
381	<	* <tt>null</tt>.  (This is useful in determining the length of the
381	>	* {@code null}.  (This is useful in determining the length of the
382		* list <i>only</i> if the caller knows that the list does not contain
383		* any null elements.)
384		*
#	Line 337 | Line 409 | public class ArrayList<E> extends Abstra
409		return (E) elementData[index];
410		}
411
412	+	@SuppressWarnings("unchecked")
413	+	static <E> E elementAt(Object[] es, int index) {
414	+	return (E) es[index];
415	+	}
416	+
417		/**
418		* Returns the element at the specified position in this list.
419		*
#	Line 345 | Line 422 | public class ArrayList<E> extends Abstra
422		* @throws IndexOutOfBoundsException {@inheritDoc}
423		*/
424		public E get(int index) {
425	<	rangeCheck(index);
349	<
425	>	Objects.checkIndex(index, size);
426		return elementData(index);
427		}
428
#	Line 360 | Line 436 | public class ArrayList<E> extends Abstra
436		* @throws IndexOutOfBoundsException {@inheritDoc}
437		*/
438		public E set(int index, E element) {
439	<	rangeCheck(index);
364	<
439	>	Objects.checkIndex(index, size);
440		E oldValue = elementData(index);
441		elementData[index] = element;
442		return oldValue;
443		}
444
445		/**
446	+	* This helper method split out from add(E) to keep method
447	+	* bytecode size under 35 (the -XX:MaxInlineSize default value),
448	+	* which helps when add(E) is called in a C1-compiled loop.
449	+	*/
450	+	private void add(E e, Object[] elementData, int s) {
451	+	if (s == elementData.length)
452	+	elementData = grow();
453	+	elementData[s] = e;
454	+	size = s + 1;
455	+	}
456	+
457	+	/**
458		* Appends the specified element to the end of this list.
459		*
460		* @param e element to be appended to this list
461	<	* @return <tt>true</tt> (as specified by {@link Collection#add})
461	>	* @return {@code true} (as specified by {@link Collection#add})
462		*/
463		public boolean add(E e) {
464	<	ensureCapacity(size + 1);  // Increments modCount!!
465	<	elementData[size++] = e;
464	>	modCount++;
465	>	add(e, elementData, size);
466		return true;
467		}
468
#	Line 390 | Line 477 | public class ArrayList<E> extends Abstra
477		*/
478		public void add(int index, E element) {
479		rangeCheckForAdd(index);
480	<
481	<	ensureCapacity(size+1);  // Increments modCount!!
482	<	System.arraycopy(elementData, index, elementData, index + 1,
483	<	size - index);
480	>	modCount++;
481	>	final int s;
482	>	Object[] elementData;
483	>	if ((s = size) == (elementData = this.elementData).length)
484	>	elementData = grow();
485	>	System.arraycopy(elementData, index,
486	>	elementData, index + 1,
487	>	s - index);
488		elementData[index] = element;
489	<	size++;
489	>	size = s + 1;
490	>	// checkInvariants();
491		}
492
493		/**
#	Line 408 | Line 500 | public class ArrayList<E> extends Abstra
500		* @throws IndexOutOfBoundsException {@inheritDoc}
501		*/
502		public E remove(int index) {
503	<	rangeCheck(index);
504	<
413	<	modCount++;
414	<	E oldValue = elementData(index);
503	>	Objects.checkIndex(index, size);
504	>	final Object[] es = elementData;
505
506	<	int numMoved = size - index - 1;
507	<	if (numMoved > 0)
418	<	System.arraycopy(elementData, index+1, elementData, index,
419	<	numMoved);
420	<	elementData[--size] = null; // Let gc do its work
506	>	@SuppressWarnings("unchecked") E oldValue = (E) es[index];
507	>	fastRemove(es, index);
508
509	+	// checkInvariants();
510		return oldValue;
511		}
512
513		/**
514	+	* {@inheritDoc}
515	+	*/
516	+	public boolean equals(Object o) {
517	+	if (o == this) {
518	+	return true;
519	+	}
520	+
521	+	if (!(o instanceof List)) {
522	+	return false;
523	+	}
524	+
525	+	final int expectedModCount = modCount;
526	+	// ArrayList can be subclassed and given arbitrary behavior, but we can
527	+	// still deal with the common case where o is ArrayList precisely
528	+	boolean equal = (o.getClass() == ArrayList.class)
529	+	? equalsArrayList((ArrayList<?>) o)
530	+	: equalsRange((List<?>) o, 0, size);
531	+
532	+	checkForComodification(expectedModCount);
533	+	return equal;
534	+	}
535	+
536	+	boolean equalsRange(List<?> other, int from, int to) {
537	+	final Object[] es = elementData;
538	+	if (to > es.length) {
539	+	throw new ConcurrentModificationException();
540	+	}
541	+	var oit = other.iterator();
542	+	for (; from < to; from++) {
543	+	if (!oit.hasNext() || !Objects.equals(es[from], oit.next())) {
544	+	return false;
545	+	}
546	+	}
547	+	return !oit.hasNext();
548	+	}
549	+
550	+	private boolean equalsArrayList(ArrayList<?> other) {
551	+	final int otherModCount = other.modCount;
552	+	final int s = size;
553	+	boolean equal;
554	+	if (equal = (s == other.size)) {
555	+	final Object[] otherEs = other.elementData;
556	+	final Object[] es = elementData;
557	+	if (s > es.length || s > otherEs.length) {
558	+	throw new ConcurrentModificationException();
559	+	}
560	+	for (int i = 0; i < s; i++) {
561	+	if (!Objects.equals(es[i], otherEs[i])) {
562	+	equal = false;
563	+	break;
564	+	}
565	+	}
566	+	}
567	+	other.checkForComodification(otherModCount);
568	+	return equal;
569	+	}
570	+
571	+	private void checkForComodification(final int expectedModCount) {
572	+	if (modCount != expectedModCount) {
573	+	throw new ConcurrentModificationException();
574	+	}
575	+	}
576	+
577	+	/**
578	+	* {@inheritDoc}
579	+	*/
580	+	public int hashCode() {
581	+	int expectedModCount = modCount;
582	+	int hash = hashCodeRange(0, size);
583	+	checkForComodification(expectedModCount);
584	+	return hash;
585	+	}
586	+
587	+	int hashCodeRange(int from, int to) {
588	+	final Object[] es = elementData;
589	+	if (to > es.length) {
590	+	throw new ConcurrentModificationException();
591	+	}
592	+	int hashCode = 1;
593	+	for (int i = from; i < to; i++) {
594	+	Object e = es[i];
595	+	hashCode = 31 * hashCode + (e == null ? 0 : e.hashCode());
596	+	}
597	+	return hashCode;
598	+	}
599	+
600	+	/**
601		* Removes the first occurrence of the specified element from this list,
602		* if it is present.  If the list does not contain the element, it is
603		* unchanged.  More formally, removes the element with the lowest index
604	<	* <tt>i</tt> such that
605	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>
606	<	* (if such an element exists).  Returns <tt>true</tt> if this list
604	>	* {@code i} such that
605	>	* {@code Objects.equals(o, get(i))}
606	>	* (if such an element exists).  Returns {@code true} if this list
607		* contained the specified element (or equivalently, if this list
608		* changed as a result of the call).
609		*
610		* @param o element to be removed from this list, if present
611	<	* @return <tt>true</tt> if this list contained the specified element
611	>	* @return {@code true} if this list contained the specified element
612		*/
613		public boolean remove(Object o) {
614	<	if (o == null) {
615	<	for (int index = 0; index < size; index++)
616	<	if (elementData[index] == null) {
617	<	fastRemove(index);
618	<	return true;
619	<	}
620	<	} else {
621	<	for (int index = 0; index < size; index++)
622	<	if (o.equals(elementData[index])) {
623	<	fastRemove(index);
624	<	return true;
625	<	}
614	>	final Object[] es = elementData;
615	>	final int size = this.size;
616	>	int i = 0;
617	>	found: {
618	>	if (o == null) {
619	>	for (; i < size; i++)
620	>	if (es[i] == null)
621	>	break found;
622	>	} else {
623	>	for (; i < size; i++)
624	>	if (o.equals(es[i]))
625	>	break found;
626	>	}
627	>	return false;
628		}
629	<	return false;
629	>	fastRemove(es, i);
630	>	return true;
631		}
632
633	<	/*
633	>	/**
634		* Private remove method that skips bounds checking and does not
635		* return the value removed.
636		*/
637	<	private void fastRemove(int index) {
637	>	private void fastRemove(Object[] es, int i) {
638		modCount++;
639	<	int numMoved = size - index - 1;
640	<	if (numMoved > 0)
641	<	System.arraycopy(elementData, index+1, elementData, index,
642	<	numMoved);
465	<	elementData[--size] = null; // Let gc do its work
639	>	final int newSize;
640	>	if ((newSize = size - 1) > i)
641	>	System.arraycopy(es, i + 1, es, i, newSize - i);
642	>	es[size = newSize] = null;
643		}
644
645		/**
#	Line 471 | Line 648 | public class ArrayList<E> extends Abstra
648		*/
649		public void clear() {
650		modCount++;
651	<
652	<	// Let gc do its work
653	<	for (int i = 0; i < size; i++)
477	<	elementData[i] = null;
478	<
479	<	size = 0;
651	>	final Object[] es = elementData;
652	>	for (int to = size, i = size = 0; i < to; i++)
653	>	es[i] = null;
654		}
655
656		/**
#	Line 489 | Line 663 | public class ArrayList<E> extends Abstra
663		* list is nonempty.)
664		*
665		* @param c collection containing elements to be added to this list
666	<	* @return <tt>true</tt> if this list changed as a result of the call
666	>	* @return {@code true} if this list changed as a result of the call
667		* @throws NullPointerException if the specified collection is null
668		*/
669		public boolean addAll(Collection<? extends E> c) {
670		Object[] a = c.toArray();
671	+	modCount++;
672		int numNew = a.length;
673	<	ensureCapacity(size + numNew);  // Increments modCount
674	<	System.arraycopy(a, 0, elementData, size, numNew);
675	<	size += numNew;
676	<	return numNew != 0;
673	>	if (numNew == 0)
674	>	return false;
675	>	Object[] elementData;
676	>	final int s;
677	>	if (numNew > (elementData = this.elementData).length - (s = size))
678	>	elementData = grow(s + numNew);
679	>	System.arraycopy(a, 0, elementData, s, numNew);
680	>	size = s + numNew;
681	>	// checkInvariants();
682	>	return true;
683		}
684
685		/**
#	Line 512 | Line 693 | public class ArrayList<E> extends Abstra
693		* @param index index at which to insert the first element from the
694		*              specified collection
695		* @param c collection containing elements to be added to this list
696	<	* @return <tt>true</tt> if this list changed as a result of the call
696	>	* @return {@code true} if this list changed as a result of the call
697		* @throws IndexOutOfBoundsException {@inheritDoc}
698		* @throws NullPointerException if the specified collection is null
699		*/
#	Line 520 | Line 701 | public class ArrayList<E> extends Abstra
701		rangeCheckForAdd(index);
702
703		Object[] a = c.toArray();
704	+	modCount++;
705		int numNew = a.length;
706	<	ensureCapacity(size + numNew);  // Increments modCount
706	>	if (numNew == 0)
707	>	return false;
708	>	Object[] elementData;
709	>	final int s;
710	>	if (numNew > (elementData = this.elementData).length - (s = size))
711	>	elementData = grow(s + numNew);
712
713	<	int numMoved = size - index;
713	>	int numMoved = s - index;
714		if (numMoved > 0)
715	<	System.arraycopy(elementData, index, elementData, index + numNew,
715	>	System.arraycopy(elementData, index,
716	>	elementData, index + numNew,
717		numMoved);
530	–
718		System.arraycopy(a, 0, elementData, index, numNew);
719	<	size += numNew;
720	<	return numNew != 0;
719	>	size = s + numNew;
720	>	// checkInvariants();
721	>	return true;
722		}
723
724		/**
#	Line 543 | Line 731 | public class ArrayList<E> extends Abstra
731		* @throws IndexOutOfBoundsException if {@code fromIndex} or
732		*         {@code toIndex} is out of range
733		*         ({@code fromIndex < 0 ||
546	–	*          fromIndex >= size() ||
734		*          toIndex > size() ||
735		*          toIndex < fromIndex})
736		*/
737		protected void removeRange(int fromIndex, int toIndex) {
738	+	if (fromIndex > toIndex) {
739	+	throw new IndexOutOfBoundsException(
740	+	outOfBoundsMsg(fromIndex, toIndex));
741	+	}
742		modCount++;
743	<	int numMoved = size - toIndex;
744	<	System.arraycopy(elementData, toIndex, elementData, fromIndex,
554	<	numMoved);
555	<
556	<	// Let gc do its work
557	<	int newSize = size - (toIndex-fromIndex);
558	<	while (size != newSize)
559	<	elementData[--size] = null;
743	>	shiftTailOverGap(elementData, fromIndex, toIndex);
744	>	// checkInvariants();
745		}
746
747	<	/**
748	<	* Checks if the given index is in range.  If not, throws an appropriate
749	<	* runtime exception.  This method does *not* check if the index is
750	<	* negative: It is always used immediately prior to an array access,
751	<	* which throws an ArrayIndexOutOfBoundsException if index is negative.
567	<	*/
568	<	private void rangeCheck(int index) {
569	<	if (index >= size)
570	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
747	>	/** Erases the gap from lo to hi, by sliding down following elements. */
748	>	private void shiftTailOverGap(Object[] es, int lo, int hi) {
749	>	System.arraycopy(es, hi, es, lo, size - hi);
750	>	for (int to = size, i = (size -= hi - lo); i < to; i++)
751	>	es[i] = null;
752		}
753
754		/**
#	Line 588 | Line 769 | public class ArrayList<E> extends Abstra
769		}
770
771		/**
772	+	* A version used in checking (fromIndex > toIndex) condition
773	+	*/
774	+	private static String outOfBoundsMsg(int fromIndex, int toIndex) {
775	+	return "From Index: " + fromIndex + " > To Index: " + toIndex;
776	+	}
777	+
778	+	/**
779		* Removes from this list all of its elements that are contained in the
780		* specified collection.
781		*
782		* @param c collection containing elements to be removed from this list
783		* @return {@code true} if this list changed as a result of the call
784		* @throws ClassCastException if the class of an element of this list
785	<	*         is incompatible with the specified collection (optional)
785	>	*         is incompatible with the specified collection
786	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
787		* @throws NullPointerException if this list contains a null element and the
788	<	*         specified collection does not permit null elements (optional),
788	>	*         specified collection does not permit null elements
789	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
790		*         or if the specified collection is null
791		* @see Collection#contains(Object)
792		*/
793		public boolean removeAll(Collection<?> c) {
794	<	return batchRemove(c, false);
794	>	return batchRemove(c, false, 0, size);
795		}
796
797		/**
#	Line 612 | Line 802 | public class ArrayList<E> extends Abstra
802		* @param c collection containing elements to be retained in this list
803		* @return {@code true} if this list changed as a result of the call
804		* @throws ClassCastException if the class of an element of this list
805	<	*         is incompatible with the specified collection (optional)
805	>	*         is incompatible with the specified collection
806	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
807		* @throws NullPointerException if this list contains a null element and the
808	<	*         specified collection does not permit null elements (optional),
808	>	*         specified collection does not permit null elements
809	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
810		*         or if the specified collection is null
811		* @see Collection#contains(Object)
812		*/
813		public boolean retainAll(Collection<?> c) {
814	<	return batchRemove(c, true);
814	>	return batchRemove(c, true, 0, size);
815		}
816
817	<	private boolean batchRemove(Collection<?> c, boolean complement) {
818	<	final Object[] elementData = this.elementData;
819	<	int r = 0, w = 0;
820	<	boolean modified = false;
817	>	boolean batchRemove(Collection<?> c, boolean complement,
818	>	final int from, final int end) {
819	>	Objects.requireNonNull(c);
820	>	final Object[] es = elementData;
821	>	int r;
822	>	// Optimize for initial run of survivors
823	>	for (r = from;; r++) {
824	>	if (r == end)
825	>	return false;
826	>	if (c.contains(es[r]) != complement)
827	>	break;
828	>	}
829	>	int w = r++;
830		try {
831	<	for (; r < size; r++)
832	<	if (c.contains(elementData[r]) == complement)
833	<	elementData[w++] = elementData[r];
834	<	} finally {
831	>	for (Object e; r < end; r++)
832	>	if (c.contains(e = es[r]) == complement)
833	>	es[w++] = e;
834	>	} catch (Throwable ex) {
835		// Preserve behavioral compatibility with AbstractCollection,
836		// even if c.contains() throws.
837	<	if (r != size) {
838	<	System.arraycopy(elementData, r,
839	<	elementData, w,
840	<	size - r);
841	<	w += size - r;
842	<	}
642	<	if (w != size) {
643	<	for (int i = w; i < size; i++)
644	<	elementData[i] = null;
645	<	modCount += size - w;
646	<	size = w;
647	<	modified = true;
648	<	}
837	>	System.arraycopy(es, r, es, w, end - r);
838	>	w += end - r;
839	>	throw ex;
840	>	} finally {
841	>	modCount += end - w;
842	>	shiftTailOverGap(es, w, end);
843		}
844	<	return modified;
844	>	// checkInvariants();
845	>	return true;
846		}
847
848		/**
849	<	* Save the state of the <tt>ArrayList</tt> instance to a stream (that
850	<	* is, serialize it).
849	>	* Saves the state of the {@code ArrayList} instance to a stream
850	>	* (that is, serializes it).
851		*
852	<	* @serialData The length of the array backing the <tt>ArrayList</tt>
852	>	* @param s the stream
853	>	* @throws java.io.IOException if an I/O error occurs
854	>	* @serialData The length of the array backing the {@code ArrayList}
855		*             instance is emitted (int), followed by all of its elements
856	<	*             (each an <tt>Object</tt>) in the proper order.
856	>	*             (each an {@code Object}) in the proper order.
857		*/
858		private void writeObject(java.io.ObjectOutputStream s)
859	<	throws java.io.IOException{
859	>	throws java.io.IOException {
860		// Write out element count, and any hidden stuff
861		int expectedModCount = modCount;
862		s.defaultWriteObject();
863
864	<	// Write out array length
865	<	s.writeInt(elementData.length);
864	>	// Write out size as capacity for behavioral compatibility with clone()
865	>	s.writeInt(size);
866
867		// Write out all elements in the proper order.
868	<	for (int i=0; i<size; i++)
868	>	for (int i=0; i<size; i++) {
869		s.writeObject(elementData[i]);
870	+	}
871
872		if (modCount != expectedModCount) {
873		throw new ConcurrentModificationException();
874		}
677	–
875		}
876
877		/**
878	<	* Reconstitute the <tt>ArrayList</tt> instance from a stream (that is,
879	<	* deserialize it).
878	>	* Reconstitutes the {@code ArrayList} instance from a stream (that is,
879	>	* deserializes it).
880	>	* @param s the stream
881	>	* @throws ClassNotFoundException if the class of a serialized object
882	>	*         could not be found
883	>	* @throws java.io.IOException if an I/O error occurs
884		*/
885		private void readObject(java.io.ObjectInputStream s)
886		throws java.io.IOException, ClassNotFoundException {
887	+
888		// Read in size, and any hidden stuff
889		s.defaultReadObject();
890
891	<	// Read in array length and allocate array
892	<	int arrayLength = s.readInt();
893	<	Object[] a = elementData = new Object[arrayLength];
894	<
895	<	// Read in all elements in the proper order.
896	<	for (int i=0; i<size; i++)
897	<	a[i] = s.readObject();
891	>	// Read in capacity
892	>	s.readInt(); // ignored
893	>
894	>	if (size > 0) {
895	>	// like clone(), allocate array based upon size not capacity
896	>	jsr166.Platform.checkArray(s, Object[].class, size);
897	>	Object[] elements = new Object[size];
898	>
899	>	// Read in all elements in the proper order.
900	>	for (int i = 0; i < size; i++) {
901	>	elements[i] = s.readObject();
902	>	}
903	>
904	>	elementData = elements;
905	>	} else if (size == 0) {
906	>	elementData = EMPTY_ELEMENTDATA;
907	>	} else {
908	>	throw new java.io.InvalidObjectException("Invalid size: " + size);
909	>	}
910		}
911
912		/**
#	Line 708 | Line 922 | public class ArrayList<E> extends Abstra
922		* @throws IndexOutOfBoundsException {@inheritDoc}
923		*/
924		public ListIterator<E> listIterator(int index) {
925	<	if (index < 0 || index > size)
712	<	throw new IndexOutOfBoundsException("Index: "+index);
925	>	rangeCheckForAdd(index);
926		return new ListItr(index);
927		}
928
#	Line 744 | Line 957 | public class ArrayList<E> extends Abstra
957		int lastRet = -1; // index of last element returned; -1 if no such
958		int expectedModCount = modCount;
959
960	+	// prevent creating a synthetic constructor
961	+	Itr() {}
962	+
963		public boolean hasNext() {
964		return cursor != size;
965		}
#	Line 776 | Line 992 | public class ArrayList<E> extends Abstra
992		}
993		}
994
995	+	@Override
996	+	public void forEachRemaining(Consumer<? super E> action) {
997	+	Objects.requireNonNull(action);
998	+	final int size = ArrayList.this.size;
999	+	int i = cursor;
1000	+	if (i < size) {
1001	+	final Object[] es = elementData;
1002	+	if (i >= es.length)
1003	+	throw new ConcurrentModificationException();
1004	+	for (; i < size && modCount == expectedModCount; i++)
1005	+	action.accept(elementAt(es, i));
1006	+	// update once at end to reduce heap write traffic
1007	+	cursor = i;
1008	+	lastRet = i - 1;
1009	+	checkForComodification();
1010	+	}
1011	+	}
1012	+
1013		final void checkForComodification() {
1014		if (modCount != expectedModCount)
1015		throw new ConcurrentModificationException();
#	Line 874 | Line 1108 | public class ArrayList<E> extends Abstra
1108		*/
1109		public List<E> subList(int fromIndex, int toIndex) {
1110		subListRangeCheck(fromIndex, toIndex, size);
1111	<	return new SubList(this, 0, fromIndex, toIndex);
1111	>	return new SubList<>(this, fromIndex, toIndex);
1112		}
1113
1114	<	static void subListRangeCheck(int fromIndex, int toIndex, int size) {
1115	<	if (fromIndex < 0)
1116	<	throw new IndexOutOfBoundsException("fromIndex = " + fromIndex);
883	<	if (toIndex > size)
884	<	throw new IndexOutOfBoundsException("toIndex = " + toIndex);
885	<	if (fromIndex > toIndex)
886	<	throw new IllegalArgumentException("fromIndex(" + fromIndex +
887	<	") > toIndex(" + toIndex + ")");
888	<	}
889	<
890	<	private class SubList extends AbstractList<E> implements RandomAccess {
891	<	private final AbstractList<E> parent;
892	<	private final int parentOffset;
1114	>	private static class SubList<E> extends AbstractList<E> implements RandomAccess {
1115	>	private final ArrayList<E> root;
1116	>	private final SubList<E> parent;
1117		private final int offset;
1118	<	int size;
1118	>	private int size;
1119	>
1120	>	/**
1121	>	* Constructs a sublist of an arbitrary ArrayList.
1122	>	*/
1123	>	public SubList(ArrayList<E> root, int fromIndex, int toIndex) {
1124	>	this.root = root;
1125	>	this.parent = null;
1126	>	this.offset = fromIndex;
1127	>	this.size = toIndex - fromIndex;
1128	>	this.modCount = root.modCount;
1129	>	}
1130
1131	<	SubList(AbstractList<E> parent,
1132	<	int offset, int fromIndex, int toIndex) {
1131	>	/**
1132	>	* Constructs a sublist of another SubList.
1133	>	*/
1134	>	private SubList(SubList<E> parent, int fromIndex, int toIndex) {
1135	>	this.root = parent.root;
1136		this.parent = parent;
1137	<	this.parentOffset = fromIndex;
900	<	this.offset = offset + fromIndex;
1137	>	this.offset = parent.offset + fromIndex;
1138		this.size = toIndex - fromIndex;
1139	<	this.modCount = ArrayList.this.modCount;
1139	>	this.modCount = root.modCount;
1140		}
1141
1142	<	public E set(int index, E e) {
1143	<	rangeCheck(index);
1142	>	public E set(int index, E element) {
1143	>	Objects.checkIndex(index, size);
1144		checkForComodification();
1145	<	E oldValue = ArrayList.this.elementData(offset + index);
1146	<	ArrayList.this.elementData[offset + index] = e;
1145	>	E oldValue = root.elementData(offset + index);
1146	>	root.elementData[offset + index] = element;
1147		return oldValue;
1148		}
1149
1150		public E get(int index) {
1151	<	rangeCheck(index);
1151	>	Objects.checkIndex(index, size);
1152		checkForComodification();
1153	<	return ArrayList.this.elementData(offset + index);
1153	>	return root.elementData(offset + index);
1154		}
1155
1156		public int size() {
1157		checkForComodification();
1158	<	return this.size;
1158	>	return size;
1159		}
1160
1161	<	public void add(int index, E e) {
1161	>	public void add(int index, E element) {
1162		rangeCheckForAdd(index);
1163		checkForComodification();
1164	<	parent.add(parentOffset + index, e);
1165	<	this.modCount = parent.modCount;
929	<	this.size++;
1164	>	root.add(offset + index, element);
1165	>	updateSizeAndModCount(1);
1166		}
1167
1168		public E remove(int index) {
1169	<	rangeCheck(index);
1169	>	Objects.checkIndex(index, size);
1170		checkForComodification();
1171	<	E result = parent.remove(parentOffset + index);
1172	<	this.modCount = parent.modCount;
937	<	this.size--;
1171	>	E result = root.remove(offset + index);
1172	>	updateSizeAndModCount(-1);
1173		return result;
1174		}
1175
1176		protected void removeRange(int fromIndex, int toIndex) {
1177		checkForComodification();
1178	<	parent.removeRange(parentOffset + fromIndex,
1179	<	parentOffset + toIndex);
945	<	this.modCount = parent.modCount;
946	<	this.size -= toIndex - fromIndex;
1178	>	root.removeRange(offset + fromIndex, offset + toIndex);
1179	>	updateSizeAndModCount(fromIndex - toIndex);
1180		}
1181
1182		public boolean addAll(Collection<? extends E> c) {
#	Line 955 | Line 1188 | public class ArrayList<E> extends Abstra
1188		int cSize = c.size();
1189		if (cSize==0)
1190		return false;
958	–
1191		checkForComodification();
1192	<	parent.addAll(parentOffset + index, c);
1193	<	this.modCount = parent.modCount;
962	<	this.size += cSize;
1192	>	root.addAll(offset + index, c);
1193	>	updateSizeAndModCount(cSize);
1194		return true;
1195		}
1196
1197	+	public void replaceAll(UnaryOperator<E> operator) {
1198	+	root.replaceAllRange(operator, offset, offset + size);
1199	+	}
1200	+
1201	+	public boolean removeAll(Collection<?> c) {
1202	+	return batchRemove(c, false);
1203	+	}
1204	+
1205	+	public boolean retainAll(Collection<?> c) {
1206	+	return batchRemove(c, true);
1207	+	}
1208	+
1209	+	private boolean batchRemove(Collection<?> c, boolean complement) {
1210	+	checkForComodification();
1211	+	int oldSize = root.size;
1212	+	boolean modified =
1213	+	root.batchRemove(c, complement, offset, offset + size);
1214	+	if (modified)
1215	+	updateSizeAndModCount(root.size - oldSize);
1216	+	return modified;
1217	+	}
1218	+
1219	+	public boolean removeIf(Predicate<? super E> filter) {
1220	+	checkForComodification();
1221	+	int oldSize = root.size;
1222	+	boolean modified = root.removeIf(filter, offset, offset + size);
1223	+	if (modified)
1224	+	updateSizeAndModCount(root.size - oldSize);
1225	+	return modified;
1226	+	}
1227	+
1228	+	public Object[] toArray() {
1229	+	checkForComodification();
1230	+	return Arrays.copyOfRange(root.elementData, offset, offset + size);
1231	+	}
1232	+
1233	+	@SuppressWarnings("unchecked")
1234	+	public <T> T[] toArray(T[] a) {
1235	+	checkForComodification();
1236	+	if (a.length < size)
1237	+	return (T[]) Arrays.copyOfRange(
1238	+	root.elementData, offset, offset + size, a.getClass());
1239	+	System.arraycopy(root.elementData, offset, a, 0, size);
1240	+	if (a.length > size)
1241	+	a[size] = null;
1242	+	return a;
1243	+	}
1244	+
1245	+	public boolean equals(Object o) {
1246	+	if (o == this) {
1247	+	return true;
1248	+	}
1249	+
1250	+	if (!(o instanceof List)) {
1251	+	return false;
1252	+	}
1253	+
1254	+	boolean equal = root.equalsRange((List<?>)o, offset, offset + size);
1255	+	checkForComodification();
1256	+	return equal;
1257	+	}
1258	+
1259	+	public int hashCode() {
1260	+	int hash = root.hashCodeRange(offset, offset + size);
1261	+	checkForComodification();
1262	+	return hash;
1263	+	}
1264	+
1265	+	public int indexOf(Object o) {
1266	+	int index = root.indexOfRange(o, offset, offset + size);
1267	+	checkForComodification();
1268	+	return index >= 0 ? index - offset : -1;
1269	+	}
1270	+
1271	+	public int lastIndexOf(Object o) {
1272	+	int index = root.lastIndexOfRange(o, offset, offset + size);
1273	+	checkForComodification();
1274	+	return index >= 0 ? index - offset : -1;
1275	+	}
1276	+
1277	+	public boolean contains(Object o) {
1278	+	return indexOf(o) >= 0;
1279	+	}
1280	+
1281		public Iterator<E> iterator() {
1282		return listIterator();
1283		}
1284
1285	<	public ListIterator<E> listIterator(final int index) {
1285	>	public ListIterator<E> listIterator(int index) {
1286		checkForComodification();
1287		rangeCheckForAdd(index);
973	–	final int offset = this.offset;
1288
1289		return new ListIterator<E>() {
1290		int cursor = index;
1291		int lastRet = -1;
1292	<	int expectedModCount = ArrayList.this.modCount;
1292	>	int expectedModCount = root.modCount;
1293
1294		public boolean hasNext() {
1295		return cursor != SubList.this.size;
#	Line 987 | Line 1301 | public class ArrayList<E> extends Abstra
1301		int i = cursor;
1302		if (i >= SubList.this.size)
1303		throw new NoSuchElementException();
1304	<	Object[] elementData = ArrayList.this.elementData;
1304	>	Object[] elementData = root.elementData;
1305		if (offset + i >= elementData.length)
1306		throw new ConcurrentModificationException();
1307		cursor = i + 1;
#	Line 1004 | Line 1318 | public class ArrayList<E> extends Abstra
1318		int i = cursor - 1;
1319		if (i < 0)
1320		throw new NoSuchElementException();
1321	<	Object[] elementData = ArrayList.this.elementData;
1321	>	Object[] elementData = root.elementData;
1322		if (offset + i >= elementData.length)
1323		throw new ConcurrentModificationException();
1324		cursor = i;
1325		return (E) elementData[offset + (lastRet = i)];
1326		}
1327
1328	+	public void forEachRemaining(Consumer<? super E> action) {
1329	+	Objects.requireNonNull(action);
1330	+	final int size = SubList.this.size;
1331	+	int i = cursor;
1332	+	if (i < size) {
1333	+	final Object[] es = root.elementData;
1334	+	if (offset + i >= es.length)
1335	+	throw new ConcurrentModificationException();
1336	+	for (; i < size && modCount == expectedModCount; i++)
1337	+	action.accept(elementAt(es, offset + i));
1338	+	// update once at end to reduce heap write traffic
1339	+	cursor = i;
1340	+	lastRet = i - 1;
1341	+	checkForComodification();
1342	+	}
1343	+	}
1344	+
1345		public int nextIndex() {
1346		return cursor;
1347		}
#	Line 1028 | Line 1359 | public class ArrayList<E> extends Abstra
1359		SubList.this.remove(lastRet);
1360		cursor = lastRet;
1361		lastRet = -1;
1362	<	expectedModCount = ArrayList.this.modCount;
1362	>	expectedModCount = root.modCount;
1363		} catch (IndexOutOfBoundsException ex) {
1364		throw new ConcurrentModificationException();
1365		}
#	Line 1040 | Line 1371 | public class ArrayList<E> extends Abstra
1371		checkForComodification();
1372
1373		try {
1374	<	ArrayList.this.set(offset + lastRet, e);
1374	>	root.set(offset + lastRet, e);
1375		} catch (IndexOutOfBoundsException ex) {
1376		throw new ConcurrentModificationException();
1377		}
#	Line 1054 | Line 1385 | public class ArrayList<E> extends Abstra
1385		SubList.this.add(i, e);
1386		cursor = i + 1;
1387		lastRet = -1;
1388	<	expectedModCount = ArrayList.this.modCount;
1388	>	expectedModCount = root.modCount;
1389		} catch (IndexOutOfBoundsException ex) {
1390		throw new ConcurrentModificationException();
1391		}
1392		}
1393
1394		final void checkForComodification() {
1395	<	if (expectedModCount != ArrayList.this.modCount)
1395	>	if (root.modCount != expectedModCount)
1396		throw new ConcurrentModificationException();
1397		}
1398		};
#	Line 1069 | Line 1400 | public class ArrayList<E> extends Abstra
1400
1401		public List<E> subList(int fromIndex, int toIndex) {
1402		subListRangeCheck(fromIndex, toIndex, size);
1403	<	return new SubList(this, offset, fromIndex, toIndex);
1073	<	}
1074	<
1075	<	private void rangeCheck(int index) {
1076	<	if (index < 0 || index >= this.size)
1077	<	throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
1403	>	return new SubList<>(this, fromIndex, toIndex);
1404		}
1405
1406		private void rangeCheckForAdd(int index) {
#	Line 1087 | Line 1413 | public class ArrayList<E> extends Abstra
1413		}
1414
1415		private void checkForComodification() {
1416	<	if (ArrayList.this.modCount != this.modCount)
1416	>	if (root.modCount != modCount)
1417		throw new ConcurrentModificationException();
1418		}
1419	+
1420	+	private void updateSizeAndModCount(int sizeChange) {
1421	+	SubList<E> slist = this;
1422	+	do {
1423	+	slist.size += sizeChange;
1424	+	slist.modCount = root.modCount;
1425	+	slist = slist.parent;
1426	+	} while (slist != null);
1427	+	}
1428	+
1429	+	public Spliterator<E> spliterator() {
1430	+	checkForComodification();
1431	+
1432	+	// ArrayListSpliterator not used here due to late-binding
1433	+	return new Spliterator<E>() {
1434	+	private int index = offset; // current index, modified on advance/split
1435	+	private int fence = -1; // -1 until used; then one past last index
1436	+	private int expectedModCount; // initialized when fence set
1437	+
1438	+	private int getFence() { // initialize fence to size on first use
1439	+	int hi; // (a specialized variant appears in method forEach)
1440	+	if ((hi = fence) < 0) {
1441	+	expectedModCount = modCount;
1442	+	hi = fence = offset + size;
1443	+	}
1444	+	return hi;
1445	+	}
1446	+
1447	+	public ArrayList<E>.ArrayListSpliterator trySplit() {
1448	+	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1449	+	// ArrayListSpliterator can be used here as the source is already bound
1450	+	return (lo >= mid) ? null : // divide range in half unless too small
1451	+	root.new ArrayListSpliterator(lo, index = mid, expectedModCount);
1452	+	}
1453	+
1454	+	public boolean tryAdvance(Consumer<? super E> action) {
1455	+	Objects.requireNonNull(action);
1456	+	int hi = getFence(), i = index;
1457	+	if (i < hi) {
1458	+	index = i + 1;
1459	+	@SuppressWarnings("unchecked") E e = (E)root.elementData[i];
1460	+	action.accept(e);
1461	+	if (root.modCount != expectedModCount)
1462	+	throw new ConcurrentModificationException();
1463	+	return true;
1464	+	}
1465	+	return false;
1466	+	}
1467	+
1468	+	public void forEachRemaining(Consumer<? super E> action) {
1469	+	Objects.requireNonNull(action);
1470	+	int i, hi, mc; // hoist accesses and checks from loop
1471	+	ArrayList<E> lst = root;
1472	+	Object[] a;
1473	+	if ((a = lst.elementData) != null) {
1474	+	if ((hi = fence) < 0) {
1475	+	mc = modCount;
1476	+	hi = offset + size;
1477	+	}
1478	+	else
1479	+	mc = expectedModCount;
1480	+	if ((i = index) >= 0 && (index = hi) <= a.length) {
1481	+	for (; i < hi; ++i) {
1482	+	@SuppressWarnings("unchecked") E e = (E) a[i];
1483	+	action.accept(e);
1484	+	}
1485	+	if (lst.modCount == mc)
1486	+	return;
1487	+	}
1488	+	}
1489	+	throw new ConcurrentModificationException();
1490	+	}
1491	+
1492	+	public long estimateSize() {
1493	+	return getFence() - index;
1494	+	}
1495	+
1496	+	public int characteristics() {
1497	+	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1498	+	}
1499	+	};
1500	+	}
1501	+	}
1502	+
1503	+	/**
1504	+	* @throws NullPointerException {@inheritDoc}
1505	+	*/
1506	+	@Override
1507	+	public void forEach(Consumer<? super E> action) {
1508	+	Objects.requireNonNull(action);
1509	+	final int expectedModCount = modCount;
1510	+	final Object[] es = elementData;
1511	+	final int size = this.size;
1512	+	for (int i = 0; modCount == expectedModCount && i < size; i++)
1513	+	action.accept(elementAt(es, i));
1514	+	if (modCount != expectedModCount)
1515	+	throw new ConcurrentModificationException();
1516	+	}
1517	+
1518	+	/**
1519	+	* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
1520	+	* and <em>fail-fast</em> {@link Spliterator} over the elements in this
1521	+	* list.
1522	+	*
1523	+	* <p>The {@code Spliterator} reports {@link Spliterator#SIZED},
1524	+	* {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}.
1525	+	* Overriding implementations should document the reporting of additional
1526	+	* characteristic values.
1527	+	*
1528	+	* @return a {@code Spliterator} over the elements in this list
1529	+	* @since 1.8
1530	+	*/
1531	+	@Override
1532	+	public Spliterator<E> spliterator() {
1533	+	return new ArrayListSpliterator(0, -1, 0);
1534	+	}
1535	+
1536	+	/** Index-based split-by-two, lazily initialized Spliterator */
1537	+	final class ArrayListSpliterator implements Spliterator<E> {
1538	+
1539	+	/*
1540	+	* If ArrayLists were immutable, or structurally immutable (no
1541	+	* adds, removes, etc), we could implement their spliterators
1542	+	* with Arrays.spliterator. Instead we detect as much
1543	+	* interference during traversal as practical without
1544	+	* sacrificing much performance. We rely primarily on
1545	+	* modCounts. These are not guaranteed to detect concurrency
1546	+	* violations, and are sometimes overly conservative about
1547	+	* within-thread interference, but detect enough problems to
1548	+	* be worthwhile in practice. To carry this out, we (1) lazily
1549	+	* initialize fence and expectedModCount until the latest
1550	+	* point that we need to commit to the state we are checking
1551	+	* against; thus improving precision.  (This doesn't apply to
1552	+	* SubLists, that create spliterators with current non-lazy
1553	+	* values).  (2) We perform only a single
1554	+	* ConcurrentModificationException check at the end of forEach
1555	+	* (the most performance-sensitive method). When using forEach
1556	+	* (as opposed to iterators), we can normally only detect
1557	+	* interference after actions, not before. Further
1558	+	* CME-triggering checks apply to all other possible
1559	+	* violations of assumptions for example null or too-small
1560	+	* elementData array given its size(), that could only have
1561	+	* occurred due to interference.  This allows the inner loop
1562	+	* of forEach to run without any further checks, and
1563	+	* simplifies lambda-resolution. While this does entail a
1564	+	* number of checks, note that in the common case of
1565	+	* list.stream().forEach(a), no checks or other computation
1566	+	* occur anywhere other than inside forEach itself.  The other
1567	+	* less-often-used methods cannot take advantage of most of
1568	+	* these streamlinings.
1569	+	*/
1570	+
1571	+	private int index; // current index, modified on advance/split
1572	+	private int fence; // -1 until used; then one past last index
1573	+	private int expectedModCount; // initialized when fence set
1574	+
1575	+	/** Creates new spliterator covering the given range. */
1576	+	ArrayListSpliterator(int origin, int fence, int expectedModCount) {
1577	+	this.index = origin;
1578	+	this.fence = fence;
1579	+	this.expectedModCount = expectedModCount;
1580	+	}
1581	+
1582	+	private int getFence() { // initialize fence to size on first use
1583	+	int hi; // (a specialized variant appears in method forEach)
1584	+	if ((hi = fence) < 0) {
1585	+	expectedModCount = modCount;
1586	+	hi = fence = size;
1587	+	}
1588	+	return hi;
1589	+	}
1590	+
1591	+	public ArrayListSpliterator trySplit() {
1592	+	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1593	+	return (lo >= mid) ? null : // divide range in half unless too small
1594	+	new ArrayListSpliterator(lo, index = mid, expectedModCount);
1595	+	}
1596	+
1597	+	public boolean tryAdvance(Consumer<? super E> action) {
1598	+	if (action == null)
1599	+	throw new NullPointerException();
1600	+	int hi = getFence(), i = index;
1601	+	if (i < hi) {
1602	+	index = i + 1;
1603	+	@SuppressWarnings("unchecked") E e = (E)elementData[i];
1604	+	action.accept(e);
1605	+	if (modCount != expectedModCount)
1606	+	throw new ConcurrentModificationException();
1607	+	return true;
1608	+	}
1609	+	return false;
1610	+	}
1611	+
1612	+	public void forEachRemaining(Consumer<? super E> action) {
1613	+	int i, hi, mc; // hoist accesses and checks from loop
1614	+	Object[] a;
1615	+	if (action == null)
1616	+	throw new NullPointerException();
1617	+	if ((a = elementData) != null) {
1618	+	if ((hi = fence) < 0) {
1619	+	mc = modCount;
1620	+	hi = size;
1621	+	}
1622	+	else
1623	+	mc = expectedModCount;
1624	+	if ((i = index) >= 0 && (index = hi) <= a.length) {
1625	+	for (; i < hi; ++i) {
1626	+	@SuppressWarnings("unchecked") E e = (E) a[i];
1627	+	action.accept(e);
1628	+	}
1629	+	if (modCount == mc)
1630	+	return;
1631	+	}
1632	+	}
1633	+	throw new ConcurrentModificationException();
1634	+	}
1635	+
1636	+	public long estimateSize() {
1637	+	return getFence() - index;
1638	+	}
1639	+
1640	+	public int characteristics() {
1641	+	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1642	+	}
1643	+	}
1644	+
1645	+	// A tiny bit set implementation
1646	+
1647	+	private static long[] nBits(int n) {
1648	+	return new long[((n - 1) >> 6) + 1];
1649	+	}
1650	+	private static void setBit(long[] bits, int i) {
1651	+	bits[i >> 6] |= 1L << i;
1652	+	}
1653	+	private static boolean isClear(long[] bits, int i) {
1654	+	return (bits[i >> 6] & (1L << i)) == 0;
1655	+	}
1656	+
1657	+	/**
1658	+	* @throws NullPointerException {@inheritDoc}
1659	+	*/
1660	+	@Override
1661	+	public boolean removeIf(Predicate<? super E> filter) {
1662	+	return removeIf(filter, 0, size);
1663	+	}
1664	+
1665	+	/**
1666	+	* Removes all elements satisfying the given predicate, from index
1667	+	* i (inclusive) to index end (exclusive).
1668	+	*/
1669	+	boolean removeIf(Predicate<? super E> filter, int i, final int end) {
1670	+	Objects.requireNonNull(filter);
1671	+	int expectedModCount = modCount;
1672	+	final Object[] es = elementData;
1673	+	// Optimize for initial run of survivors
1674	+	for (; i < end && !filter.test(elementAt(es, i)); i++)
1675	+	;
1676	+	// Tolerate predicates that reentrantly access the collection for
1677	+	// read (but writers still get CME), so traverse once to find
1678	+	// elements to delete, a second pass to physically expunge.
1679	+	if (i < end) {
1680	+	final int beg = i;
1681	+	final long[] deathRow = nBits(end - beg);
1682	+	deathRow[0] = 1L;   // set bit 0
1683	+	for (i = beg + 1; i < end; i++)
1684	+	if (filter.test(elementAt(es, i)))
1685	+	setBit(deathRow, i - beg);
1686	+	if (modCount != expectedModCount)
1687	+	throw new ConcurrentModificationException();
1688	+	modCount++;
1689	+	int w = beg;
1690	+	for (i = beg; i < end; i++)
1691	+	if (isClear(deathRow, i - beg))
1692	+	es[w++] = es[i];
1693	+	shiftTailOverGap(es, w, end);
1694	+	// checkInvariants();
1695	+	return true;
1696	+	} else {
1697	+	if (modCount != expectedModCount)
1698	+	throw new ConcurrentModificationException();
1699	+	// checkInvariants();
1700	+	return false;
1701	+	}
1702	+	}
1703	+
1704	+	@Override
1705	+	public void replaceAll(UnaryOperator<E> operator) {
1706	+	replaceAllRange(operator, 0, size);
1707	+	// TODO(8203662): remove increment of modCount from ...
1708	+	modCount++;
1709	+	}
1710	+
1711	+	private void replaceAllRange(UnaryOperator<E> operator, int i, int end) {
1712	+	Objects.requireNonNull(operator);
1713	+	final int expectedModCount = modCount;
1714	+	final Object[] es = elementData;
1715	+	for (; modCount == expectedModCount && i < end; i++)
1716	+	es[i] = operator.apply(elementAt(es, i));
1717	+	if (modCount != expectedModCount)
1718	+	throw new ConcurrentModificationException();
1719	+	// checkInvariants();
1720	+	}
1721	+
1722	+	@Override
1723	+	@SuppressWarnings("unchecked")
1724	+	public void sort(Comparator<? super E> c) {
1725	+	final int expectedModCount = modCount;
1726	+	Arrays.sort((E[]) elementData, 0, size, c);
1727	+	if (modCount != expectedModCount)
1728	+	throw new ConcurrentModificationException();
1729	+	modCount++;
1730	+	// checkInvariants();
1731	+	}
1732	+
1733	+	void checkInvariants() {
1734	+	// assert size >= 0;
1735	+	// assert size == elementData.length || elementData[size] == null;
1736		}
1737		}

Diff Legend

–	Removed lines
+	Added lines
<	Changed lines
>	Changed lines