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Comparing jsr166/src/main/java/util/ArrayList.java (file contents):
Revision 1.30 by jsr166, Sun Sep 5 21:32:19 2010 UTC vs.
Revision 1.71 by jsr166, Fri Jul 24 20:57:26 2020 UTC

#	Line 1 | Line 1
1		/*
2	<	* Copyright (c) 1997, 2008, Oracle and/or its affiliates. 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 25 | Line 25
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	+	// OPENJDK @java.io.Serial
113		private static final long serialVersionUID = 8683452581122892189L;
114
115		/**
116	+	* Default initial capacity.
117	+	*/
118	+	private static final int DEFAULT_CAPACITY = 10;
119	+
120	+	/**
121	+	* Shared empty array instance used for empty instances.
122	+	*/
123	+	private static final Object[] EMPTY_ELEMENTDATA = {};
124	+
125	+	/**
126	+	* Shared empty array instance used for default sized empty instances. We
127	+	* distinguish this from EMPTY_ELEMENTDATA to know how much to inflate when
128	+	* first element is added.
129	+	*/
130	+	private static final Object[] DEFAULTCAPACITY_EMPTY_ELEMENTDATA = {};
131	+
132	+	/**
133		* The array buffer into which the elements of the ArrayList are stored.
134	<	* The capacity of the ArrayList is the length of this array buffer.
134	>	* The capacity of the ArrayList is the length of this array buffer. Any
135	>	* empty ArrayList with elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
136	>	* will be expanded to DEFAULT_CAPACITY when the first element is added.
137		*/
138	<	private transient Object[] elementData;
138	>	transient Object[] elementData; // non-private to simplify nested class access
139
140		/**
141		* The size of the ArrayList (the number of elements it contains).
#	Line 120 | Line 147 | public class ArrayList<E> extends Abstra
147		/**
148		* Constructs an empty list with the specified initial capacity.
149		*
150	<	* @param   initialCapacity   the initial capacity of the list
151	<	* @exception IllegalArgumentException if the specified initial capacity
152	<	*            is negative
150	>	* @param  initialCapacity  the initial capacity of the list
151	>	* @throws IllegalArgumentException if the specified initial capacity
152	>	*         is negative
153		*/
154		public ArrayList(int initialCapacity) {
155	<	super();
156	<	if (initialCapacity < 0)
155	>	if (initialCapacity > 0) {
156	>	this.elementData = new Object[initialCapacity];
157	>	} else if (initialCapacity == 0) {
158	>	this.elementData = EMPTY_ELEMENTDATA;
159	>	} else {
160		throw new IllegalArgumentException("Illegal Capacity: "+
161		initialCapacity);
162	<	this.elementData = new Object[initialCapacity];
162	>	}
163		}
164
165		/**
166		* Constructs an empty list with an initial capacity of ten.
167		*/
168		public ArrayList() {
169	<	this(10);
169	>	this.elementData = DEFAULTCAPACITY_EMPTY_ELEMENTDATA;
170		}
171
172		/**
#	Line 148 | Line 178 | public class ArrayList<E> extends Abstra
178		* @throws NullPointerException if the specified collection is null
179		*/
180		public ArrayList(Collection<? extends E> c) {
181	<	elementData = c.toArray();
182	<	size = elementData.length;
183	<	// c.toArray might (incorrectly) not return Object[] (see 6260652)
184	<	if (elementData.getClass() != Object[].class)
185	<	elementData = Arrays.copyOf(elementData, size, Object[].class);
181	>	Object[] a = c.toArray();
182	>	if ((size = a.length) != 0) {
183	>	if (c.getClass() == ArrayList.class) {
184	>	elementData = a;
185	>	} else {
186	>	elementData = Arrays.copyOf(a, size, Object[].class);
187	>	}
188	>	} else {
189	>	// replace with empty array.
190	>	elementData = EMPTY_ELEMENTDATA;
191	>	}
192		}
193
194		/**
195	<	* Trims the capacity of this <tt>ArrayList</tt> instance to be the
195	>	* Trims the capacity of this {@code ArrayList} instance to be the
196		* list's current size.  An application can use this operation to minimize
197	<	* the storage of an <tt>ArrayList</tt> instance.
197	>	* the storage of an {@code ArrayList} instance.
198		*/
199		public void trimToSize() {
200		modCount++;
201	<	int oldCapacity = elementData.length;
202	<	if (size < oldCapacity) {
203	<	elementData = Arrays.copyOf(elementData, size);
201	>	if (size < elementData.length) {
202	>	elementData = (size == 0)
203	>	? EMPTY_ELEMENTDATA
204	>	: Arrays.copyOf(elementData, size);
205		}
206		}
207
208		/**
209	<	* Increases the capacity of this <tt>ArrayList</tt> instance, if
209	>	* Increases the capacity of this {@code ArrayList} instance, if
210		* necessary, to ensure that it can hold at least the number of elements
211		* specified by the minimum capacity argument.
212		*
213	<	* @param   minCapacity   the desired minimum capacity
213	>	* @param minCapacity the desired minimum capacity
214		*/
215		public void ensureCapacity(int minCapacity) {
216	<	modCount++;
216	>	if (minCapacity > elementData.length
217	>	&& !(elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA
218	>	&& minCapacity <= DEFAULT_CAPACITY)) {
219	>	modCount++;
220	>	grow(minCapacity);
221	>	}
222	>	}
223	>
224	>	/**
225	>	* Increases the capacity to ensure that it can hold at least the
226	>	* number of elements specified by the minimum capacity argument.
227	>	*
228	>	* @param minCapacity the desired minimum capacity
229	>	* @throws OutOfMemoryError if minCapacity is less than zero
230	>	*/
231	>	private Object[] grow(int minCapacity) {
232		int oldCapacity = elementData.length;
233	<	if (minCapacity > oldCapacity) {
234	<	int newCapacity = (oldCapacity * 3)/2 + 1;
235	<	if (newCapacity < minCapacity)
236	<	newCapacity = minCapacity;
237	<	// minCapacity is usually close to size, so this is a win:
238	<	elementData = Arrays.copyOf(elementData, newCapacity);
233	>	if (oldCapacity > 0 || elementData != DEFAULTCAPACITY_EMPTY_ELEMENTDATA) {
234	>	int newCapacity = ArraysSupport.newLength(oldCapacity,
235	>	minCapacity - oldCapacity, /* minimum growth */
236	>	oldCapacity >> 1           /* preferred growth */);
237	>	return elementData = Arrays.copyOf(elementData, newCapacity);
238	>	} else {
239	>	return elementData = new Object[Math.max(DEFAULT_CAPACITY, minCapacity)];
240		}
241		}
242
243	+	private Object[] grow() {
244	+	return grow(size + 1);
245	+	}
246	+
247		/**
248		* Returns the number of elements in this list.
249		*
#	Line 197 | Line 254 | public class ArrayList<E> extends Abstra
254		}
255
256		/**
257	<	* Returns <tt>true</tt> if this list contains no elements.
257	>	* Returns {@code true} if this list contains no elements.
258		*
259	<	* @return <tt>true</tt> if this list contains no elements
259	>	* @return {@code true} if this list contains no elements
260		*/
261		public boolean isEmpty() {
262		return size == 0;
263		}
264
265		/**
266	<	* Returns <tt>true</tt> if this list contains the specified element.
267	<	* More formally, returns <tt>true</tt> if and only if this list contains
268	<	* at least one element <tt>e</tt> such that
269	<	* <tt>(o==null&nbsp;?&nbsp;e==null&nbsp;:&nbsp;o.equals(e))</tt>.
266	>	* Returns {@code true} if this list contains the specified element.
267	>	* More formally, returns {@code true} if and only if this list contains
268	>	* at least one element {@code e} such that
269	>	* {@code Objects.equals(o, e)}.
270		*
271		* @param o element whose presence in this list is to be tested
272	<	* @return <tt>true</tt> if this list contains the specified element
272	>	* @return {@code true} if this list contains the specified element
273		*/
274		public boolean contains(Object o) {
275		return indexOf(o) >= 0;
#	Line 221 | Line 278 | public class ArrayList<E> extends Abstra
278		/**
279		* Returns the index of the first occurrence of the specified element
280		* in this list, or -1 if this list does not contain the element.
281	<	* More formally, returns the lowest index <tt>i</tt> such that
282	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
281	>	* More formally, returns the lowest index {@code i} such that
282	>	* {@code Objects.equals(o, get(i))},
283		* or -1 if there is no such index.
284		*/
285		public int indexOf(Object o) {
286	+	return indexOfRange(o, 0, size);
287	+	}
288	+
289	+	int indexOfRange(Object o, int start, int end) {
290	+	Object[] es = elementData;
291		if (o == null) {
292	<	for (int i = 0; i < size; i++)
293	<	if (elementData[i]==null)
292	>	for (int i = start; i < end; i++) {
293	>	if (es[i] == null) {
294		return i;
295	+	}
296	+	}
297		} else {
298	<	for (int i = 0; i < size; i++)
299	<	if (o.equals(elementData[i]))
298	>	for (int i = start; i < end; i++) {
299	>	if (o.equals(es[i])) {
300		return i;
301	+	}
302	+	}
303		}
304		return -1;
305		}
#	Line 241 | Line 307 | public class ArrayList<E> extends Abstra
307		/**
308		* Returns the index of the last occurrence of the specified element
309		* in this list, or -1 if this list does not contain the element.
310	<	* More formally, returns the highest index <tt>i</tt> such that
311	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>,
310	>	* More formally, returns the highest index {@code i} such that
311	>	* {@code Objects.equals(o, get(i))},
312		* or -1 if there is no such index.
313		*/
314		public int lastIndexOf(Object o) {
315	+	return lastIndexOfRange(o, 0, size);
316	+	}
317	+
318	+	int lastIndexOfRange(Object o, int start, int end) {
319	+	Object[] es = elementData;
320		if (o == null) {
321	<	for (int i = size-1; i >= 0; i--)
322	<	if (elementData[i]==null)
321	>	for (int i = end - 1; i >= start; i--) {
322	>	if (es[i] == null) {
323		return i;
324	+	}
325	+	}
326		} else {
327	<	for (int i = size-1; i >= 0; i--)
328	<	if (o.equals(elementData[i]))
327	>	for (int i = end - 1; i >= start; i--) {
328	>	if (o.equals(es[i])) {
329		return i;
330	+	}
331	+	}
332		}
333		return -1;
334		}
335
336		/**
337	<	* Returns a shallow copy of this <tt>ArrayList</tt> instance.  (The
337	>	* Returns a shallow copy of this {@code ArrayList} instance.  (The
338		* elements themselves are not copied.)
339		*
340	<	* @return a clone of this <tt>ArrayList</tt> instance
340	>	* @return a clone of this {@code ArrayList} instance
341		*/
342		public Object clone() {
343		try {
344	<	@SuppressWarnings("unchecked")
270	<	ArrayList<E> v = (ArrayList<E>) super.clone();
344	>	ArrayList<?> v = (ArrayList<?>) super.clone();
345		v.elementData = Arrays.copyOf(elementData, size);
346		v.modCount = 0;
347		return v;
348		} catch (CloneNotSupportedException e) {
349		// this shouldn't happen, since we are Cloneable
350	<	throw new InternalError();
350	>	throw new InternalError(e);
351		}
352		}
353
#	Line 306 | Line 380 | public class ArrayList<E> extends Abstra
380		* <p>If the list fits in the specified array with room to spare
381		* (i.e., the array has more elements than the list), the element in
382		* the array immediately following the end of the collection is set to
383	<	* <tt>null</tt>.  (This is useful in determining the length of the
383	>	* {@code null}.  (This is useful in determining the length of the
384		* list <i>only</i> if the caller knows that the list does not contain
385		* any null elements.)
386		*
#	Line 337 | Line 411 | public class ArrayList<E> extends Abstra
411		return (E) elementData[index];
412		}
413
414	+	@SuppressWarnings("unchecked")
415	+	static <E> E elementAt(Object[] es, int index) {
416	+	return (E) es[index];
417	+	}
418	+
419		/**
420		* Returns the element at the specified position in this list.
421		*
#	Line 345 | Line 424 | public class ArrayList<E> extends Abstra
424		* @throws IndexOutOfBoundsException {@inheritDoc}
425		*/
426		public E get(int index) {
427	<	rangeCheck(index);
349	<
427	>	Objects.checkIndex(index, size);
428		return elementData(index);
429		}
430
#	Line 360 | Line 438 | public class ArrayList<E> extends Abstra
438		* @throws IndexOutOfBoundsException {@inheritDoc}
439		*/
440		public E set(int index, E element) {
441	<	rangeCheck(index);
364	<
441	>	Objects.checkIndex(index, size);
442		E oldValue = elementData(index);
443		elementData[index] = element;
444		return oldValue;
445		}
446
447		/**
448	+	* This helper method split out from add(E) to keep method
449	+	* bytecode size under 35 (the -XX:MaxInlineSize default value),
450	+	* which helps when add(E) is called in a C1-compiled loop.
451	+	*/
452	+	private void add(E e, Object[] elementData, int s) {
453	+	if (s == elementData.length)
454	+	elementData = grow();
455	+	elementData[s] = e;
456	+	size = s + 1;
457	+	}
458	+
459	+	/**
460		* Appends the specified element to the end of this list.
461		*
462		* @param e element to be appended to this list
463	<	* @return <tt>true</tt> (as specified by {@link Collection#add})
463	>	* @return {@code true} (as specified by {@link Collection#add})
464		*/
465		public boolean add(E e) {
466	<	ensureCapacity(size + 1);  // Increments modCount!!
467	<	elementData[size++] = e;
466	>	modCount++;
467	>	add(e, elementData, size);
468		return true;
469		}
470
#	Line 390 | Line 479 | public class ArrayList<E> extends Abstra
479		*/
480		public void add(int index, E element) {
481		rangeCheckForAdd(index);
482	<
483	<	ensureCapacity(size+1);  // Increments modCount!!
484	<	System.arraycopy(elementData, index, elementData, index + 1,
485	<	size - index);
482	>	modCount++;
483	>	final int s;
484	>	Object[] elementData;
485	>	if ((s = size) == (elementData = this.elementData).length)
486	>	elementData = grow();
487	>	System.arraycopy(elementData, index,
488	>	elementData, index + 1,
489	>	s - index);
490		elementData[index] = element;
491	<	size++;
491	>	size = s + 1;
492	>	// checkInvariants();
493		}
494
495		/**
#	Line 408 | Line 502 | public class ArrayList<E> extends Abstra
502		* @throws IndexOutOfBoundsException {@inheritDoc}
503		*/
504		public E remove(int index) {
505	<	rangeCheck(index);
505	>	Objects.checkIndex(index, size);
506	>	final Object[] es = elementData;
507
508	<	modCount++;
509	<	E oldValue = elementData(index);
415	<
416	<	int numMoved = size - index - 1;
417	<	if (numMoved > 0)
418	<	System.arraycopy(elementData, index+1, elementData, index,
419	<	numMoved);
420	<	elementData[--size] = null; // Let gc do its work
508	>	@SuppressWarnings("unchecked") E oldValue = (E) es[index];
509	>	fastRemove(es, index);
510
511	+	// checkInvariants();
512		return oldValue;
513		}
514
515		/**
516	+	* {@inheritDoc}
517	+	*/
518	+	public boolean equals(Object o) {
519	+	if (o == this) {
520	+	return true;
521	+	}
522	+
523	+	if (!(o instanceof List)) {
524	+	return false;
525	+	}
526	+
527	+	final int expectedModCount = modCount;
528	+	// ArrayList can be subclassed and given arbitrary behavior, but we can
529	+	// still deal with the common case where o is ArrayList precisely
530	+	boolean equal = (o.getClass() == ArrayList.class)
531	+	? equalsArrayList((ArrayList<?>) o)
532	+	: equalsRange((List<?>) o, 0, size);
533	+
534	+	checkForComodification(expectedModCount);
535	+	return equal;
536	+	}
537	+
538	+	boolean equalsRange(List<?> other, int from, int to) {
539	+	final Object[] es = elementData;
540	+	if (to > es.length) {
541	+	throw new ConcurrentModificationException();
542	+	}
543	+	var oit = other.iterator();
544	+	for (; from < to; from++) {
545	+	if (!oit.hasNext() || !Objects.equals(es[from], oit.next())) {
546	+	return false;
547	+	}
548	+	}
549	+	return !oit.hasNext();
550	+	}
551	+
552	+	private boolean equalsArrayList(ArrayList<?> other) {
553	+	final int otherModCount = other.modCount;
554	+	final int s = size;
555	+	boolean equal;
556	+	if (equal = (s == other.size)) {
557	+	final Object[] otherEs = other.elementData;
558	+	final Object[] es = elementData;
559	+	if (s > es.length || s > otherEs.length) {
560	+	throw new ConcurrentModificationException();
561	+	}
562	+	for (int i = 0; i < s; i++) {
563	+	if (!Objects.equals(es[i], otherEs[i])) {
564	+	equal = false;
565	+	break;
566	+	}
567	+	}
568	+	}
569	+	other.checkForComodification(otherModCount);
570	+	return equal;
571	+	}
572	+
573	+	private void checkForComodification(final int expectedModCount) {
574	+	if (modCount != expectedModCount) {
575	+	throw new ConcurrentModificationException();
576	+	}
577	+	}
578	+
579	+	/**
580	+	* {@inheritDoc}
581	+	*/
582	+	public int hashCode() {
583	+	int expectedModCount = modCount;
584	+	int hash = hashCodeRange(0, size);
585	+	checkForComodification(expectedModCount);
586	+	return hash;
587	+	}
588	+
589	+	int hashCodeRange(int from, int to) {
590	+	final Object[] es = elementData;
591	+	if (to > es.length) {
592	+	throw new ConcurrentModificationException();
593	+	}
594	+	int hashCode = 1;
595	+	for (int i = from; i < to; i++) {
596	+	Object e = es[i];
597	+	hashCode = 31 * hashCode + (e == null ? 0 : e.hashCode());
598	+	}
599	+	return hashCode;
600	+	}
601	+
602	+	/**
603		* Removes the first occurrence of the specified element from this list,
604		* if it is present.  If the list does not contain the element, it is
605		* unchanged.  More formally, removes the element with the lowest index
606	<	* <tt>i</tt> such that
607	<	* <tt>(o==null&nbsp;?&nbsp;get(i)==null&nbsp;:&nbsp;o.equals(get(i)))</tt>
608	<	* (if such an element exists).  Returns <tt>true</tt> if this list
606	>	* {@code i} such that
607	>	* {@code Objects.equals(o, get(i))}
608	>	* (if such an element exists).  Returns {@code true} if this list
609		* contained the specified element (or equivalently, if this list
610		* changed as a result of the call).
611		*
612		* @param o element to be removed from this list, if present
613	<	* @return <tt>true</tt> if this list contained the specified element
613	>	* @return {@code true} if this list contained the specified element
614		*/
615		public boolean remove(Object o) {
616	<	if (o == null) {
617	<	for (int index = 0; index < size; index++)
618	<	if (elementData[index] == null) {
619	<	fastRemove(index);
620	<	return true;
621	<	}
622	<	} else {
623	<	for (int index = 0; index < size; index++)
624	<	if (o.equals(elementData[index])) {
625	<	fastRemove(index);
626	<	return true;
627	<	}
616	>	final Object[] es = elementData;
617	>	final int size = this.size;
618	>	int i = 0;
619	>	found: {
620	>	if (o == null) {
621	>	for (; i < size; i++)
622	>	if (es[i] == null)
623	>	break found;
624	>	} else {
625	>	for (; i < size; i++)
626	>	if (o.equals(es[i]))
627	>	break found;
628	>	}
629	>	return false;
630		}
631	<	return false;
631	>	fastRemove(es, i);
632	>	return true;
633		}
634
635	<	/*
635	>	/**
636		* Private remove method that skips bounds checking and does not
637		* return the value removed.
638		*/
639	<	private void fastRemove(int index) {
639	>	private void fastRemove(Object[] es, int i) {
640		modCount++;
641	<	int numMoved = size - index - 1;
642	<	if (numMoved > 0)
643	<	System.arraycopy(elementData, index+1, elementData, index,
644	<	numMoved);
465	<	elementData[--size] = null; // Let gc do its work
641	>	final int newSize;
642	>	if ((newSize = size - 1) > i)
643	>	System.arraycopy(es, i + 1, es, i, newSize - i);
644	>	es[size = newSize] = null;
645		}
646
647		/**
#	Line 471 | Line 650 | public class ArrayList<E> extends Abstra
650		*/
651		public void clear() {
652		modCount++;
653	<
654	<	// Let gc do its work
655	<	for (int i = 0; i < size; i++)
477	<	elementData[i] = null;
478	<
479	<	size = 0;
653	>	final Object[] es = elementData;
654	>	for (int to = size, i = size = 0; i < to; i++)
655	>	es[i] = null;
656		}
657
658		/**
#	Line 489 | Line 665 | public class ArrayList<E> extends Abstra
665		* list is nonempty.)
666		*
667		* @param c collection containing elements to be added to this list
668	<	* @return <tt>true</tt> if this list changed as a result of the call
668	>	* @return {@code true} if this list changed as a result of the call
669		* @throws NullPointerException if the specified collection is null
670		*/
671		public boolean addAll(Collection<? extends E> c) {
672		Object[] a = c.toArray();
673	+	modCount++;
674		int numNew = a.length;
675	<	ensureCapacity(size + numNew);  // Increments modCount
676	<	System.arraycopy(a, 0, elementData, size, numNew);
677	<	size += numNew;
678	<	return numNew != 0;
675	>	if (numNew == 0)
676	>	return false;
677	>	Object[] elementData;
678	>	final int s;
679	>	if (numNew > (elementData = this.elementData).length - (s = size))
680	>	elementData = grow(s + numNew);
681	>	System.arraycopy(a, 0, elementData, s, numNew);
682	>	size = s + numNew;
683	>	// checkInvariants();
684	>	return true;
685		}
686
687		/**
#	Line 512 | Line 695 | public class ArrayList<E> extends Abstra
695		* @param index index at which to insert the first element from the
696		*              specified collection
697		* @param c collection containing elements to be added to this list
698	<	* @return <tt>true</tt> if this list changed as a result of the call
698	>	* @return {@code true} if this list changed as a result of the call
699		* @throws IndexOutOfBoundsException {@inheritDoc}
700		* @throws NullPointerException if the specified collection is null
701		*/
#	Line 520 | Line 703 | public class ArrayList<E> extends Abstra
703		rangeCheckForAdd(index);
704
705		Object[] a = c.toArray();
706	+	modCount++;
707		int numNew = a.length;
708	<	ensureCapacity(size + numNew);  // Increments modCount
708	>	if (numNew == 0)
709	>	return false;
710	>	Object[] elementData;
711	>	final int s;
712	>	if (numNew > (elementData = this.elementData).length - (s = size))
713	>	elementData = grow(s + numNew);
714
715	<	int numMoved = size - index;
715	>	int numMoved = s - index;
716		if (numMoved > 0)
717	<	System.arraycopy(elementData, index, elementData, index + numNew,
717	>	System.arraycopy(elementData, index,
718	>	elementData, index + numNew,
719		numMoved);
530	–
720		System.arraycopy(a, 0, elementData, index, numNew);
721	<	size += numNew;
722	<	return numNew != 0;
721	>	size = s + numNew;
722	>	// checkInvariants();
723	>	return true;
724		}
725
726		/**
#	Line 543 | Line 733 | public class ArrayList<E> extends Abstra
733		* @throws IndexOutOfBoundsException if {@code fromIndex} or
734		*         {@code toIndex} is out of range
735		*         ({@code fromIndex < 0 ||
546	–	*          fromIndex >= size() ||
736		*          toIndex > size() ||
737		*          toIndex < fromIndex})
738		*/
739		protected void removeRange(int fromIndex, int toIndex) {
740	+	if (fromIndex > toIndex) {
741	+	throw new IndexOutOfBoundsException(
742	+	outOfBoundsMsg(fromIndex, toIndex));
743	+	}
744		modCount++;
745	<	int numMoved = size - toIndex;
746	<	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;
745	>	shiftTailOverGap(elementData, fromIndex, toIndex);
746	>	// checkInvariants();
747		}
748
749	<	/**
750	<	* Checks if the given index is in range.  If not, throws an appropriate
751	<	* runtime exception.  This method does *not* check if the index is
752	<	* negative: It is always used immediately prior to an array access,
753	<	* 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));
749	>	/** Erases the gap from lo to hi, by sliding down following elements. */
750	>	private void shiftTailOverGap(Object[] es, int lo, int hi) {
751	>	System.arraycopy(es, hi, es, lo, size - hi);
752	>	for (int to = size, i = (size -= hi - lo); i < to; i++)
753	>	es[i] = null;
754		}
755
756		/**
#	Line 588 | Line 771 | public class ArrayList<E> extends Abstra
771		}
772
773		/**
774	+	* A version used in checking (fromIndex > toIndex) condition
775	+	*/
776	+	private static String outOfBoundsMsg(int fromIndex, int toIndex) {
777	+	return "From Index: " + fromIndex + " > To Index: " + toIndex;
778	+	}
779	+
780	+	/**
781		* Removes from this list all of its elements that are contained in the
782		* specified collection.
783		*
784		* @param c collection containing elements to be removed from this list
785		* @return {@code true} if this list changed as a result of the call
786		* @throws ClassCastException if the class of an element of this list
787	<	*         is incompatible with the specified collection (optional)
787	>	*         is incompatible with the specified collection
788	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
789		* @throws NullPointerException if this list contains a null element and the
790	<	*         specified collection does not permit null elements (optional),
790	>	*         specified collection does not permit null elements
791	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
792		*         or if the specified collection is null
793		* @see Collection#contains(Object)
794		*/
795		public boolean removeAll(Collection<?> c) {
796	<	return batchRemove(c, false);
796	>	return batchRemove(c, false, 0, size);
797		}
798
799		/**
#	Line 612 | Line 804 | public class ArrayList<E> extends Abstra
804		* @param c collection containing elements to be retained in this list
805		* @return {@code true} if this list changed as a result of the call
806		* @throws ClassCastException if the class of an element of this list
807	<	*         is incompatible with the specified collection (optional)
807	>	*         is incompatible with the specified collection
808	>	* (<a href="Collection.html#optional-restrictions">optional</a>)
809		* @throws NullPointerException if this list contains a null element and the
810	<	*         specified collection does not permit null elements (optional),
810	>	*         specified collection does not permit null elements
811	>	* (<a href="Collection.html#optional-restrictions">optional</a>),
812		*         or if the specified collection is null
813		* @see Collection#contains(Object)
814		*/
815		public boolean retainAll(Collection<?> c) {
816	<	return batchRemove(c, true);
816	>	return batchRemove(c, true, 0, size);
817		}
818
819	<	private boolean batchRemove(Collection<?> c, boolean complement) {
820	<	final Object[] elementData = this.elementData;
821	<	int r = 0, w = 0;
822	<	boolean modified = false;
819	>	boolean batchRemove(Collection<?> c, boolean complement,
820	>	final int from, final int end) {
821	>	Objects.requireNonNull(c);
822	>	final Object[] es = elementData;
823	>	int r;
824	>	// Optimize for initial run of survivors
825	>	for (r = from;; r++) {
826	>	if (r == end)
827	>	return false;
828	>	if (c.contains(es[r]) != complement)
829	>	break;
830	>	}
831	>	int w = r++;
832		try {
833	<	for (; r < size; r++)
834	<	if (c.contains(elementData[r]) == complement)
835	<	elementData[w++] = elementData[r];
836	<	} finally {
833	>	for (Object e; r < end; r++)
834	>	if (c.contains(e = es[r]) == complement)
835	>	es[w++] = e;
836	>	} catch (Throwable ex) {
837		// Preserve behavioral compatibility with AbstractCollection,
838		// even if c.contains() throws.
839	<	if (r != size) {
840	<	System.arraycopy(elementData, r,
841	<	elementData, w,
842	<	size - r);
843	<	w += size - r;
844	<	}
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	<	}
839	>	System.arraycopy(es, r, es, w, end - r);
840	>	w += end - r;
841	>	throw ex;
842	>	} finally {
843	>	modCount += end - w;
844	>	shiftTailOverGap(es, w, end);
845		}
846	<	return modified;
846	>	// checkInvariants();
847	>	return true;
848		}
849
850		/**
851	<	* Save the state of the <tt>ArrayList</tt> instance to a stream (that
852	<	* is, serialize it).
851	>	* Saves the state of the {@code ArrayList} instance to a stream
852	>	* (that is, serializes it).
853		*
854	<	* @serialData The length of the array backing the <tt>ArrayList</tt>
854	>	* @param s the stream
855	>	* @throws java.io.IOException if an I/O error occurs
856	>	* @serialData The length of the array backing the {@code ArrayList}
857		*             instance is emitted (int), followed by all of its elements
858	<	*             (each an <tt>Object</tt>) in the proper order.
858	>	*             (each an {@code Object}) in the proper order.
859		*/
860	+	// OPENJDK @java.io.Serial
861		private void writeObject(java.io.ObjectOutputStream s)
862	<	throws java.io.IOException{
862	>	throws java.io.IOException {
863		// Write out element count, and any hidden stuff
864		int expectedModCount = modCount;
865		s.defaultWriteObject();
866
867	<	// Write out array length
868	<	s.writeInt(elementData.length);
867	>	// Write out size as capacity for behavioral compatibility with clone()
868	>	s.writeInt(size);
869
870		// Write out all elements in the proper order.
871	<	for (int i=0; i<size; i++)
871	>	for (int i=0; i<size; i++) {
872		s.writeObject(elementData[i]);
873	+	}
874
875		if (modCount != expectedModCount) {
876		throw new ConcurrentModificationException();
877		}
677	–
878		}
879
880		/**
881	<	* Reconstitute the <tt>ArrayList</tt> instance from a stream (that is,
882	<	* deserialize it).
881	>	* Reconstitutes the {@code ArrayList} instance from a stream (that is,
882	>	* deserializes it).
883	>	* @param s the stream
884	>	* @throws ClassNotFoundException if the class of a serialized object
885	>	*         could not be found
886	>	* @throws java.io.IOException if an I/O error occurs
887		*/
888	+	// OPENJDK @java.io.Serial
889		private void readObject(java.io.ObjectInputStream s)
890		throws java.io.IOException, ClassNotFoundException {
891	+
892		// Read in size, and any hidden stuff
893		s.defaultReadObject();
894
895	<	// Read in array length and allocate array
896	<	int arrayLength = s.readInt();
897	<	Object[] a = elementData = new Object[arrayLength];
898	<
899	<	// Read in all elements in the proper order.
900	<	for (int i=0; i<size; i++)
901	<	a[i] = s.readObject();
895	>	// Read in capacity
896	>	s.readInt(); // ignored
897	>
898	>	if (size > 0) {
899	>	// like clone(), allocate array based upon size not capacity
900	>	jsr166.Platform.checkArray(s, Object[].class, size);
901	>	Object[] elements = new Object[size];
902	>
903	>	// Read in all elements in the proper order.
904	>	for (int i = 0; i < size; i++) {
905	>	elements[i] = s.readObject();
906	>	}
907	>
908	>	elementData = elements;
909	>	} else if (size == 0) {
910	>	elementData = EMPTY_ELEMENTDATA;
911	>	} else {
912	>	throw new java.io.InvalidObjectException("Invalid size: " + size);
913	>	}
914		}
915
916		/**
#	Line 708 | Line 926 | public class ArrayList<E> extends Abstra
926		* @throws IndexOutOfBoundsException {@inheritDoc}
927		*/
928		public ListIterator<E> listIterator(int index) {
929	<	if (index < 0 || index > size)
712	<	throw new IndexOutOfBoundsException("Index: "+index);
929	>	rangeCheckForAdd(index);
930		return new ListItr(index);
931		}
932
#	Line 744 | Line 961 | public class ArrayList<E> extends Abstra
961		int lastRet = -1; // index of last element returned; -1 if no such
962		int expectedModCount = modCount;
963
964	+	// prevent creating a synthetic constructor
965	+	Itr() {}
966	+
967		public boolean hasNext() {
968		return cursor != size;
969		}
#	Line 776 | Line 996 | public class ArrayList<E> extends Abstra
996		}
997		}
998
999	+	@Override
1000	+	public void forEachRemaining(Consumer<? super E> action) {
1001	+	Objects.requireNonNull(action);
1002	+	final int size = ArrayList.this.size;
1003	+	int i = cursor;
1004	+	if (i < size) {
1005	+	final Object[] es = elementData;
1006	+	if (i >= es.length)
1007	+	throw new ConcurrentModificationException();
1008	+	for (; i < size && modCount == expectedModCount; i++)
1009	+	action.accept(elementAt(es, i));
1010	+	// update once at end to reduce heap write traffic
1011	+	cursor = i;
1012	+	lastRet = i - 1;
1013	+	checkForComodification();
1014	+	}
1015	+	}
1016	+
1017		final void checkForComodification() {
1018		if (modCount != expectedModCount)
1019		throw new ConcurrentModificationException();
#	Line 874 | Line 1112 | public class ArrayList<E> extends Abstra
1112		*/
1113		public List<E> subList(int fromIndex, int toIndex) {
1114		subListRangeCheck(fromIndex, toIndex, size);
1115	<	return new SubList(this, 0, fromIndex, toIndex);
1115	>	return new SubList<>(this, fromIndex, toIndex);
1116		}
1117
1118	<	static void subListRangeCheck(int fromIndex, int toIndex, int size) {
1119	<	if (fromIndex < 0)
1120	<	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;
1118	>	private static class SubList<E> extends AbstractList<E> implements RandomAccess {
1119	>	private final ArrayList<E> root;
1120	>	private final SubList<E> parent;
1121		private final int offset;
1122	<	int size;
1122	>	private int size;
1123
1124	<	SubList(AbstractList<E> parent,
1125	<	int offset, int fromIndex, int toIndex) {
1124	>	/**
1125	>	* Constructs a sublist of an arbitrary ArrayList.
1126	>	*/
1127	>	public SubList(ArrayList<E> root, int fromIndex, int toIndex) {
1128	>	this.root = root;
1129	>	this.parent = null;
1130	>	this.offset = fromIndex;
1131	>	this.size = toIndex - fromIndex;
1132	>	this.modCount = root.modCount;
1133	>	}
1134	>
1135	>	/**
1136	>	* Constructs a sublist of another SubList.
1137	>	*/
1138	>	private SubList(SubList<E> parent, int fromIndex, int toIndex) {
1139	>	this.root = parent.root;
1140		this.parent = parent;
1141	<	this.parentOffset = fromIndex;
900	<	this.offset = offset + fromIndex;
1141	>	this.offset = parent.offset + fromIndex;
1142		this.size = toIndex - fromIndex;
1143	<	this.modCount = ArrayList.this.modCount;
1143	>	this.modCount = parent.modCount;
1144		}
1145
1146	<	public E set(int index, E e) {
1147	<	rangeCheck(index);
1146	>	public E set(int index, E element) {
1147	>	Objects.checkIndex(index, size);
1148		checkForComodification();
1149	<	E oldValue = ArrayList.this.elementData(offset + index);
1150	<	ArrayList.this.elementData[offset + index] = e;
1149	>	E oldValue = root.elementData(offset + index);
1150	>	root.elementData[offset + index] = element;
1151		return oldValue;
1152		}
1153
1154		public E get(int index) {
1155	<	rangeCheck(index);
1155	>	Objects.checkIndex(index, size);
1156		checkForComodification();
1157	<	return ArrayList.this.elementData(offset + index);
1157	>	return root.elementData(offset + index);
1158		}
1159
1160		public int size() {
1161		checkForComodification();
1162	<	return this.size;
1162	>	return size;
1163		}
1164
1165	<	public void add(int index, E e) {
1165	>	public void add(int index, E element) {
1166		rangeCheckForAdd(index);
1167		checkForComodification();
1168	<	parent.add(parentOffset + index, e);
1169	<	this.modCount = parent.modCount;
929	<	this.size++;
1168	>	root.add(offset + index, element);
1169	>	updateSizeAndModCount(1);
1170		}
1171
1172		public E remove(int index) {
1173	<	rangeCheck(index);
1173	>	Objects.checkIndex(index, size);
1174		checkForComodification();
1175	<	E result = parent.remove(parentOffset + index);
1176	<	this.modCount = parent.modCount;
937	<	this.size--;
1175	>	E result = root.remove(offset + index);
1176	>	updateSizeAndModCount(-1);
1177		return result;
1178		}
1179
1180		protected void removeRange(int fromIndex, int toIndex) {
1181		checkForComodification();
1182	<	parent.removeRange(parentOffset + fromIndex,
1183	<	parentOffset + toIndex);
945	<	this.modCount = parent.modCount;
946	<	this.size -= toIndex - fromIndex;
1182	>	root.removeRange(offset + fromIndex, offset + toIndex);
1183	>	updateSizeAndModCount(fromIndex - toIndex);
1184		}
1185
1186		public boolean addAll(Collection<? extends E> c) {
#	Line 955 | Line 1192 | public class ArrayList<E> extends Abstra
1192		int cSize = c.size();
1193		if (cSize==0)
1194		return false;
958	–
1195		checkForComodification();
1196	<	parent.addAll(parentOffset + index, c);
1197	<	this.modCount = parent.modCount;
962	<	this.size += cSize;
1196	>	root.addAll(offset + index, c);
1197	>	updateSizeAndModCount(cSize);
1198		return true;
1199		}
1200
1201	+	public void replaceAll(UnaryOperator<E> operator) {
1202	+	root.replaceAllRange(operator, offset, offset + size);
1203	+	}
1204	+
1205	+	public boolean removeAll(Collection<?> c) {
1206	+	return batchRemove(c, false);
1207	+	}
1208	+
1209	+	public boolean retainAll(Collection<?> c) {
1210	+	return batchRemove(c, true);
1211	+	}
1212	+
1213	+	private boolean batchRemove(Collection<?> c, boolean complement) {
1214	+	checkForComodification();
1215	+	int oldSize = root.size;
1216	+	boolean modified =
1217	+	root.batchRemove(c, complement, offset, offset + size);
1218	+	if (modified)
1219	+	updateSizeAndModCount(root.size - oldSize);
1220	+	return modified;
1221	+	}
1222	+
1223	+	public boolean removeIf(Predicate<? super E> filter) {
1224	+	checkForComodification();
1225	+	int oldSize = root.size;
1226	+	boolean modified = root.removeIf(filter, offset, offset + size);
1227	+	if (modified)
1228	+	updateSizeAndModCount(root.size - oldSize);
1229	+	return modified;
1230	+	}
1231	+
1232	+	public Object[] toArray() {
1233	+	checkForComodification();
1234	+	return Arrays.copyOfRange(root.elementData, offset, offset + size);
1235	+	}
1236	+
1237	+	@SuppressWarnings("unchecked")
1238	+	public <T> T[] toArray(T[] a) {
1239	+	checkForComodification();
1240	+	if (a.length < size)
1241	+	return (T[]) Arrays.copyOfRange(
1242	+	root.elementData, offset, offset + size, a.getClass());
1243	+	System.arraycopy(root.elementData, offset, a, 0, size);
1244	+	if (a.length > size)
1245	+	a[size] = null;
1246	+	return a;
1247	+	}
1248	+
1249	+	public boolean equals(Object o) {
1250	+	if (o == this) {
1251	+	return true;
1252	+	}
1253	+
1254	+	if (!(o instanceof List)) {
1255	+	return false;
1256	+	}
1257	+
1258	+	boolean equal = root.equalsRange((List<?>)o, offset, offset + size);
1259	+	checkForComodification();
1260	+	return equal;
1261	+	}
1262	+
1263	+	public int hashCode() {
1264	+	int hash = root.hashCodeRange(offset, offset + size);
1265	+	checkForComodification();
1266	+	return hash;
1267	+	}
1268	+
1269	+	public int indexOf(Object o) {
1270	+	int index = root.indexOfRange(o, offset, offset + size);
1271	+	checkForComodification();
1272	+	return index >= 0 ? index - offset : -1;
1273	+	}
1274	+
1275	+	public int lastIndexOf(Object o) {
1276	+	int index = root.lastIndexOfRange(o, offset, offset + size);
1277	+	checkForComodification();
1278	+	return index >= 0 ? index - offset : -1;
1279	+	}
1280	+
1281	+	public boolean contains(Object o) {
1282	+	return indexOf(o) >= 0;
1283	+	}
1284	+
1285		public Iterator<E> iterator() {
1286		return listIterator();
1287		}
1288
1289	<	public ListIterator<E> listIterator(final int index) {
1289	>	public ListIterator<E> listIterator(int index) {
1290		checkForComodification();
1291		rangeCheckForAdd(index);
973	–	final int offset = this.offset;
1292
1293		return new ListIterator<E>() {
1294		int cursor = index;
1295		int lastRet = -1;
1296	<	int expectedModCount = ArrayList.this.modCount;
1296	>	int expectedModCount = SubList.this.modCount;
1297
1298		public boolean hasNext() {
1299		return cursor != SubList.this.size;
#	Line 987 | Line 1305 | public class ArrayList<E> extends Abstra
1305		int i = cursor;
1306		if (i >= SubList.this.size)
1307		throw new NoSuchElementException();
1308	<	Object[] elementData = ArrayList.this.elementData;
1308	>	Object[] elementData = root.elementData;
1309		if (offset + i >= elementData.length)
1310		throw new ConcurrentModificationException();
1311		cursor = i + 1;
#	Line 1004 | Line 1322 | public class ArrayList<E> extends Abstra
1322		int i = cursor - 1;
1323		if (i < 0)
1324		throw new NoSuchElementException();
1325	<	Object[] elementData = ArrayList.this.elementData;
1325	>	Object[] elementData = root.elementData;
1326		if (offset + i >= elementData.length)
1327		throw new ConcurrentModificationException();
1328		cursor = i;
1329		return (E) elementData[offset + (lastRet = i)];
1330		}
1331
1332	+	public void forEachRemaining(Consumer<? super E> action) {
1333	+	Objects.requireNonNull(action);
1334	+	final int size = SubList.this.size;
1335	+	int i = cursor;
1336	+	if (i < size) {
1337	+	final Object[] es = root.elementData;
1338	+	if (offset + i >= es.length)
1339	+	throw new ConcurrentModificationException();
1340	+	for (; i < size && root.modCount == expectedModCount; i++)
1341	+	action.accept(elementAt(es, offset + i));
1342	+	// update once at end to reduce heap write traffic
1343	+	cursor = i;
1344	+	lastRet = i - 1;
1345	+	checkForComodification();
1346	+	}
1347	+	}
1348	+
1349		public int nextIndex() {
1350		return cursor;
1351		}
#	Line 1028 | Line 1363 | public class ArrayList<E> extends Abstra
1363		SubList.this.remove(lastRet);
1364		cursor = lastRet;
1365		lastRet = -1;
1366	<	expectedModCount = ArrayList.this.modCount;
1366	>	expectedModCount = SubList.this.modCount;
1367		} catch (IndexOutOfBoundsException ex) {
1368		throw new ConcurrentModificationException();
1369		}
#	Line 1040 | Line 1375 | public class ArrayList<E> extends Abstra
1375		checkForComodification();
1376
1377		try {
1378	<	ArrayList.this.set(offset + lastRet, e);
1378	>	root.set(offset + lastRet, e);
1379		} catch (IndexOutOfBoundsException ex) {
1380		throw new ConcurrentModificationException();
1381		}
#	Line 1054 | Line 1389 | public class ArrayList<E> extends Abstra
1389		SubList.this.add(i, e);
1390		cursor = i + 1;
1391		lastRet = -1;
1392	<	expectedModCount = ArrayList.this.modCount;
1392	>	expectedModCount = SubList.this.modCount;
1393		} catch (IndexOutOfBoundsException ex) {
1394		throw new ConcurrentModificationException();
1395		}
1396		}
1397
1398		final void checkForComodification() {
1399	<	if (expectedModCount != ArrayList.this.modCount)
1399	>	if (root.modCount != expectedModCount)
1400		throw new ConcurrentModificationException();
1401		}
1402		};
#	Line 1069 | Line 1404 | public class ArrayList<E> extends Abstra
1404
1405		public List<E> subList(int fromIndex, int toIndex) {
1406		subListRangeCheck(fromIndex, toIndex, size);
1407	<	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));
1407	>	return new SubList<>(this, fromIndex, toIndex);
1408		}
1409
1410		private void rangeCheckForAdd(int index) {
#	Line 1087 | Line 1417 | public class ArrayList<E> extends Abstra
1417		}
1418
1419		private void checkForComodification() {
1420	<	if (ArrayList.this.modCount != this.modCount)
1420	>	if (root.modCount != modCount)
1421		throw new ConcurrentModificationException();
1422		}
1423	+
1424	+	private void updateSizeAndModCount(int sizeChange) {
1425	+	SubList<E> slist = this;
1426	+	do {
1427	+	slist.size += sizeChange;
1428	+	slist.modCount = root.modCount;
1429	+	slist = slist.parent;
1430	+	} while (slist != null);
1431	+	}
1432	+
1433	+	public Spliterator<E> spliterator() {
1434	+	checkForComodification();
1435	+
1436	+	// ArrayListSpliterator not used here due to late-binding
1437	+	return new Spliterator<E>() {
1438	+	private int index = offset; // current index, modified on advance/split
1439	+	private int fence = -1; // -1 until used; then one past last index
1440	+	private int expectedModCount; // initialized when fence set
1441	+
1442	+	private int getFence() { // initialize fence to size on first use
1443	+	int hi; // (a specialized variant appears in method forEach)
1444	+	if ((hi = fence) < 0) {
1445	+	expectedModCount = modCount;
1446	+	hi = fence = offset + size;
1447	+	}
1448	+	return hi;
1449	+	}
1450	+
1451	+	public ArrayList<E>.ArrayListSpliterator trySplit() {
1452	+	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1453	+	// ArrayListSpliterator can be used here as the source is already bound
1454	+	return (lo >= mid) ? null : // divide range in half unless too small
1455	+	root.new ArrayListSpliterator(lo, index = mid, expectedModCount);
1456	+	}
1457	+
1458	+	public boolean tryAdvance(Consumer<? super E> action) {
1459	+	Objects.requireNonNull(action);
1460	+	int hi = getFence(), i = index;
1461	+	if (i < hi) {
1462	+	index = i + 1;
1463	+	@SuppressWarnings("unchecked") E e = (E)root.elementData[i];
1464	+	action.accept(e);
1465	+	if (root.modCount != expectedModCount)
1466	+	throw new ConcurrentModificationException();
1467	+	return true;
1468	+	}
1469	+	return false;
1470	+	}
1471	+
1472	+	public void forEachRemaining(Consumer<? super E> action) {
1473	+	Objects.requireNonNull(action);
1474	+	int i, hi, mc; // hoist accesses and checks from loop
1475	+	ArrayList<E> lst = root;
1476	+	Object[] a;
1477	+	if ((a = lst.elementData) != null) {
1478	+	if ((hi = fence) < 0) {
1479	+	mc = modCount;
1480	+	hi = offset + size;
1481	+	}
1482	+	else
1483	+	mc = expectedModCount;
1484	+	if ((i = index) >= 0 && (index = hi) <= a.length) {
1485	+	for (; i < hi; ++i) {
1486	+	@SuppressWarnings("unchecked") E e = (E) a[i];
1487	+	action.accept(e);
1488	+	}
1489	+	if (lst.modCount == mc)
1490	+	return;
1491	+	}
1492	+	}
1493	+	throw new ConcurrentModificationException();
1494	+	}
1495	+
1496	+	public long estimateSize() {
1497	+	return getFence() - index;
1498	+	}
1499	+
1500	+	public int characteristics() {
1501	+	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1502	+	}
1503	+	};
1504	+	}
1505	+	}
1506	+
1507	+	/**
1508	+	* @throws NullPointerException {@inheritDoc}
1509	+	*/
1510	+	@Override
1511	+	public void forEach(Consumer<? super E> action) {
1512	+	Objects.requireNonNull(action);
1513	+	final int expectedModCount = modCount;
1514	+	final Object[] es = elementData;
1515	+	final int size = this.size;
1516	+	for (int i = 0; modCount == expectedModCount && i < size; i++)
1517	+	action.accept(elementAt(es, i));
1518	+	if (modCount != expectedModCount)
1519	+	throw new ConcurrentModificationException();
1520	+	}
1521	+
1522	+	/**
1523	+	* Creates a <em><a href="Spliterator.html#binding">late-binding</a></em>
1524	+	* and <em>fail-fast</em> {@link Spliterator} over the elements in this
1525	+	* list.
1526	+	*
1527	+	* <p>The {@code Spliterator} reports {@link Spliterator#SIZED},
1528	+	* {@link Spliterator#SUBSIZED}, and {@link Spliterator#ORDERED}.
1529	+	* Overriding implementations should document the reporting of additional
1530	+	* characteristic values.
1531	+	*
1532	+	* @return a {@code Spliterator} over the elements in this list
1533	+	* @since 1.8
1534	+	*/
1535	+	@Override
1536	+	public Spliterator<E> spliterator() {
1537	+	return new ArrayListSpliterator(0, -1, 0);
1538	+	}
1539	+
1540	+	/** Index-based split-by-two, lazily initialized Spliterator */
1541	+	final class ArrayListSpliterator implements Spliterator<E> {
1542	+
1543	+	/*
1544	+	* If ArrayLists were immutable, or structurally immutable (no
1545	+	* adds, removes, etc), we could implement their spliterators
1546	+	* with Arrays.spliterator. Instead we detect as much
1547	+	* interference during traversal as practical without
1548	+	* sacrificing much performance. We rely primarily on
1549	+	* modCounts. These are not guaranteed to detect concurrency
1550	+	* violations, and are sometimes overly conservative about
1551	+	* within-thread interference, but detect enough problems to
1552	+	* be worthwhile in practice. To carry this out, we (1) lazily
1553	+	* initialize fence and expectedModCount until the latest
1554	+	* point that we need to commit to the state we are checking
1555	+	* against; thus improving precision.  (This doesn't apply to
1556	+	* SubLists, that create spliterators with current non-lazy
1557	+	* values).  (2) We perform only a single
1558	+	* ConcurrentModificationException check at the end of forEach
1559	+	* (the most performance-sensitive method). When using forEach
1560	+	* (as opposed to iterators), we can normally only detect
1561	+	* interference after actions, not before. Further
1562	+	* CME-triggering checks apply to all other possible
1563	+	* violations of assumptions for example null or too-small
1564	+	* elementData array given its size(), that could only have
1565	+	* occurred due to interference.  This allows the inner loop
1566	+	* of forEach to run without any further checks, and
1567	+	* simplifies lambda-resolution. While this does entail a
1568	+	* number of checks, note that in the common case of
1569	+	* list.stream().forEach(a), no checks or other computation
1570	+	* occur anywhere other than inside forEach itself.  The other
1571	+	* less-often-used methods cannot take advantage of most of
1572	+	* these streamlinings.
1573	+	*/
1574	+
1575	+	private int index; // current index, modified on advance/split
1576	+	private int fence; // -1 until used; then one past last index
1577	+	private int expectedModCount; // initialized when fence set
1578	+
1579	+	/** Creates new spliterator covering the given range. */
1580	+	ArrayListSpliterator(int origin, int fence, int expectedModCount) {
1581	+	this.index = origin;
1582	+	this.fence = fence;
1583	+	this.expectedModCount = expectedModCount;
1584	+	}
1585	+
1586	+	private int getFence() { // initialize fence to size on first use
1587	+	int hi; // (a specialized variant appears in method forEach)
1588	+	if ((hi = fence) < 0) {
1589	+	expectedModCount = modCount;
1590	+	hi = fence = size;
1591	+	}
1592	+	return hi;
1593	+	}
1594	+
1595	+	public ArrayListSpliterator trySplit() {
1596	+	int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
1597	+	return (lo >= mid) ? null : // divide range in half unless too small
1598	+	new ArrayListSpliterator(lo, index = mid, expectedModCount);
1599	+	}
1600	+
1601	+	public boolean tryAdvance(Consumer<? super E> action) {
1602	+	if (action == null)
1603	+	throw new NullPointerException();
1604	+	int hi = getFence(), i = index;
1605	+	if (i < hi) {
1606	+	index = i + 1;
1607	+	@SuppressWarnings("unchecked") E e = (E)elementData[i];
1608	+	action.accept(e);
1609	+	if (modCount != expectedModCount)
1610	+	throw new ConcurrentModificationException();
1611	+	return true;
1612	+	}
1613	+	return false;
1614	+	}
1615	+
1616	+	public void forEachRemaining(Consumer<? super E> action) {
1617	+	int i, hi, mc; // hoist accesses and checks from loop
1618	+	Object[] a;
1619	+	if (action == null)
1620	+	throw new NullPointerException();
1621	+	if ((a = elementData) != null) {
1622	+	if ((hi = fence) < 0) {
1623	+	mc = modCount;
1624	+	hi = size;
1625	+	}
1626	+	else
1627	+	mc = expectedModCount;
1628	+	if ((i = index) >= 0 && (index = hi) <= a.length) {
1629	+	for (; i < hi; ++i) {
1630	+	@SuppressWarnings("unchecked") E e = (E) a[i];
1631	+	action.accept(e);
1632	+	}
1633	+	if (modCount == mc)
1634	+	return;
1635	+	}
1636	+	}
1637	+	throw new ConcurrentModificationException();
1638	+	}
1639	+
1640	+	public long estimateSize() {
1641	+	return getFence() - index;
1642	+	}
1643	+
1644	+	public int characteristics() {
1645	+	return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
1646	+	}
1647	+	}
1648	+
1649	+	// A tiny bit set implementation
1650	+
1651	+	private static long[] nBits(int n) {
1652	+	return new long[((n - 1) >> 6) + 1];
1653	+	}
1654	+	private static void setBit(long[] bits, int i) {
1655	+	bits[i >> 6] |= 1L << i;
1656	+	}
1657	+	private static boolean isClear(long[] bits, int i) {
1658	+	return (bits[i >> 6] & (1L << i)) == 0;
1659	+	}
1660	+
1661	+	/**
1662	+	* @throws NullPointerException {@inheritDoc}
1663	+	*/
1664	+	@Override
1665	+	public boolean removeIf(Predicate<? super E> filter) {
1666	+	return removeIf(filter, 0, size);
1667	+	}
1668	+
1669	+	/**
1670	+	* Removes all elements satisfying the given predicate, from index
1671	+	* i (inclusive) to index end (exclusive).
1672	+	*/
1673	+	boolean removeIf(Predicate<? super E> filter, int i, final int end) {
1674	+	Objects.requireNonNull(filter);
1675	+	int expectedModCount = modCount;
1676	+	final Object[] es = elementData;
1677	+	// Optimize for initial run of survivors
1678	+	for (; i < end && !filter.test(elementAt(es, i)); i++)
1679	+	;
1680	+	// Tolerate predicates that reentrantly access the collection for
1681	+	// read (but writers still get CME), so traverse once to find
1682	+	// elements to delete, a second pass to physically expunge.
1683	+	if (i < end) {
1684	+	final int beg = i;
1685	+	final long[] deathRow = nBits(end - beg);
1686	+	deathRow[0] = 1L;   // set bit 0
1687	+	for (i = beg + 1; i < end; i++)
1688	+	if (filter.test(elementAt(es, i)))
1689	+	setBit(deathRow, i - beg);
1690	+	if (modCount != expectedModCount)
1691	+	throw new ConcurrentModificationException();
1692	+	modCount++;
1693	+	int w = beg;
1694	+	for (i = beg; i < end; i++)
1695	+	if (isClear(deathRow, i - beg))
1696	+	es[w++] = es[i];
1697	+	shiftTailOverGap(es, w, end);
1698	+	// checkInvariants();
1699	+	return true;
1700	+	} else {
1701	+	if (modCount != expectedModCount)
1702	+	throw new ConcurrentModificationException();
1703	+	// checkInvariants();
1704	+	return false;
1705	+	}
1706	+	}
1707	+
1708	+	@Override
1709	+	public void replaceAll(UnaryOperator<E> operator) {
1710	+	replaceAllRange(operator, 0, size);
1711	+	// TODO(8203662): remove increment of modCount from ...
1712	+	modCount++;
1713	+	}
1714	+
1715	+	private void replaceAllRange(UnaryOperator<E> operator, int i, int end) {
1716	+	Objects.requireNonNull(operator);
1717	+	final int expectedModCount = modCount;
1718	+	final Object[] es = elementData;
1719	+	for (; modCount == expectedModCount && i < end; i++)
1720	+	es[i] = operator.apply(elementAt(es, i));
1721	+	if (modCount != expectedModCount)
1722	+	throw new ConcurrentModificationException();
1723	+	// checkInvariants();
1724	+	}
1725	+
1726	+	@Override
1727	+	@SuppressWarnings("unchecked")
1728	+	public void sort(Comparator<? super E> c) {
1729	+	final int expectedModCount = modCount;
1730	+	Arrays.sort((E[]) elementData, 0, size, c);
1731	+	if (modCount != expectedModCount)
1732	+	throw new ConcurrentModificationException();
1733	+	modCount++;
1734	+	// checkInvariants();
1735	+	}
1736	+
1737	+	void checkInvariants() {
1738	+	// assert size >= 0;
1739	+	// assert size == elementData.length || elementData[size] == null;
1740		}
1741		}

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