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 1.49 by jsr166, Wed Dec 21 05:15:36 2016 UTC vs.
Revision 1.69 by jsr166, Fri Aug 30 18:05:39 2019 UTC

#	Line 1 | Line 1
1		/*
2	<	* Copyright (c) 1997, 2016, 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
#	Line 28 | Line 28 | package java.util;
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 {@code List} interface.  Implements
#	Line 91 | Line 93 | import java.util.function.UnaryOperator;
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
#	Line 107 | Line 109 | import java.util.function.UnaryOperator;
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		/**
#	Line 218 | Line 221 | public class ArrayList<E> extends Abstra
221		}
222
223		/**
221	–	* The maximum size of array to allocate (unless necessary).
222	–	* Some VMs reserve some header words in an array.
223	–	* Attempts to allocate larger arrays may result in
224	–	* OutOfMemoryError: Requested array size exceeds VM limit
225	–	*/
226	–	private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
227	–
228	–	/**
224		* Increases the capacity to ensure that it can hold at least the
225		* number of elements specified by the minimum capacity argument.
226		*
#	Line 233 | Line 228 | public class ArrayList<E> extends Abstra
228		* @throws OutOfMemoryError if minCapacity is less than zero
229		*/
230		private Object[] grow(int minCapacity) {
231	<	return elementData = Arrays.copyOf(elementData,
232	<	newCapacity(minCapacity));
231	>	int oldCapacity = elementData.length;
232	>	if (oldCapacity > 0 || elementData != DEFAULTCAPACITY_EMPTY_ELEMENTDATA) {
233	>	int newCapacity = ArraysSupport.newLength(oldCapacity,
234	>	minCapacity - oldCapacity, /* minimum growth */
235	>	oldCapacity >> 1           /* preferred growth */);
236	>	return elementData = Arrays.copyOf(elementData, newCapacity);
237	>	} else {
238	>	return elementData = new Object[Math.max(DEFAULT_CAPACITY, minCapacity)];
239	>	}
240		}
241
242		private Object[] grow() {
#	Line 242 | Line 244 | public class ArrayList<E> extends Abstra
244		}
245
246		/**
245	–	* Returns a capacity at least as large as the given minimum capacity.
246	–	* Returns the current capacity increased by 50% if that suffices.
247	–	* Will not return a capacity greater than MAX_ARRAY_SIZE unless
248	–	* the given minimum capacity is greater than MAX_ARRAY_SIZE.
249	–	*
250	–	* @param minCapacity the desired minimum capacity
251	–	* @throws OutOfMemoryError if minCapacity is less than zero
252	–	*/
253	–	private int newCapacity(int minCapacity) {
254	–	// overflow-conscious code
255	–	int oldCapacity = elementData.length;
256	–	int newCapacity = oldCapacity + (oldCapacity >> 1);
257	–	if (newCapacity - minCapacity <= 0) {
258	–	if (elementData == DEFAULTCAPACITY_EMPTY_ELEMENTDATA)
259	–	return Math.max(DEFAULT_CAPACITY, minCapacity);
260	–	if (minCapacity < 0) // overflow
261	–	throw new OutOfMemoryError();
262	–	return minCapacity;
263	–	}
264	–	return (newCapacity - MAX_ARRAY_SIZE <= 0)
265	–	? newCapacity
266	–	: hugeCapacity(minCapacity);
267	–	}
268	–
269	–	private static int hugeCapacity(int minCapacity) {
270	–	if (minCapacity < 0) // overflow
271	–	throw new OutOfMemoryError();
272	–	return (minCapacity > MAX_ARRAY_SIZE)
273	–	? Integer.MAX_VALUE
274	–	: MAX_ARRAY_SIZE;
275	–	}
276	–
277	–	/**
247		* Returns the number of elements in this list.
248		*
249		* @return the number of elements in this list
#	Line 313 | Line 282 | public class ArrayList<E> extends Abstra
282		* or -1 if there is no such index.
283		*/
284		public int indexOf(Object o) {
285	+	return indexOfRange(o, 0, size);
286	+	}
287	+
288	+	int indexOfRange(Object o, int start, int end) {
289	+	Object[] es = elementData;
290		if (o == null) {
291	<	for (int i = 0; i < size; i++)
292	<	if (elementData[i]==null)
291	>	for (int i = start; i < end; i++) {
292	>	if (es[i] == null) {
293		return i;
294	+	}
295	+	}
296		} else {
297	<	for (int i = 0; i < size; i++)
298	<	if (o.equals(elementData[i]))
297	>	for (int i = start; i < end; i++) {
298	>	if (o.equals(es[i])) {
299		return i;
300	+	}
301	+	}
302		}
303		return -1;
304		}
#	Line 333 | Line 311 | public class ArrayList<E> extends Abstra
311		* or -1 if there is no such index.
312		*/
313		public int lastIndexOf(Object o) {
314	+	return lastIndexOfRange(o, 0, size);
315	+	}
316	+
317	+	int lastIndexOfRange(Object o, int start, int end) {
318	+	Object[] es = elementData;
319		if (o == null) {
320	<	for (int i = size-1; i >= 0; i--)
321	<	if (elementData[i]==null)
320	>	for (int i = end - 1; i >= start; i--) {
321	>	if (es[i] == null) {
322		return i;
323	+	}
324	+	}
325		} else {
326	<	for (int i = size-1; i >= 0; i--)
327	<	if (o.equals(elementData[i]))
326	>	for (int i = end - 1; i >= start; i--) {
327	>	if (o.equals(es[i])) {
328		return i;
329	+	}
330	+	}
331		}
332		return -1;
333		}
#	Line 515 | Line 502 | public class ArrayList<E> extends Abstra
502		*/
503		public E remove(int index) {
504		Objects.checkIndex(index, size);
505	+	final Object[] es = elementData;
506
507	<	modCount++;
508	<	E oldValue = elementData(index);
521	<
522	<	int numMoved = size - index - 1;
523	<	if (numMoved > 0)
524	<	System.arraycopy(elementData, index+1, elementData, index,
525	<	numMoved);
526	<	elementData[--size] = null; // clear to let GC do its work
507	>	@SuppressWarnings("unchecked") E oldValue = (E) es[index];
508	>	fastRemove(es, index);
509
510		// checkInvariants();
511		return oldValue;
512		}
513
514		/**
515	+	* {@inheritDoc}
516	+	*/
517	+	public boolean equals(Object o) {
518	+	if (o == this) {
519	+	return true;
520	+	}
521	+
522	+	if (!(o instanceof List)) {
523	+	return false;
524	+	}
525	+
526	+	final int expectedModCount = modCount;
527	+	// ArrayList can be subclassed and given arbitrary behavior, but we can
528	+	// still deal with the common case where o is ArrayList precisely
529	+	boolean equal = (o.getClass() == ArrayList.class)
530	+	? equalsArrayList((ArrayList<?>) o)
531	+	: equalsRange((List<?>) o, 0, size);
532	+
533	+	checkForComodification(expectedModCount);
534	+	return equal;
535	+	}
536	+
537	+	boolean equalsRange(List<?> other, int from, int to) {
538	+	final Object[] es = elementData;
539	+	if (to > es.length) {
540	+	throw new ConcurrentModificationException();
541	+	}
542	+	var oit = other.iterator();
543	+	for (; from < to; from++) {
544	+	if (!oit.hasNext() || !Objects.equals(es[from], oit.next())) {
545	+	return false;
546	+	}
547	+	}
548	+	return !oit.hasNext();
549	+	}
550	+
551	+	private boolean equalsArrayList(ArrayList<?> other) {
552	+	final int otherModCount = other.modCount;
553	+	final int s = size;
554	+	boolean equal;
555	+	if (equal = (s == other.size)) {
556	+	final Object[] otherEs = other.elementData;
557	+	final Object[] es = elementData;
558	+	if (s > es.length || s > otherEs.length) {
559	+	throw new ConcurrentModificationException();
560	+	}
561	+	for (int i = 0; i < s; i++) {
562	+	if (!Objects.equals(es[i], otherEs[i])) {
563	+	equal = false;
564	+	break;
565	+	}
566	+	}
567	+	}
568	+	other.checkForComodification(otherModCount);
569	+	return equal;
570	+	}
571	+
572	+	private void checkForComodification(final int expectedModCount) {
573	+	if (modCount != expectedModCount) {
574	+	throw new ConcurrentModificationException();
575	+	}
576	+	}
577	+
578	+	/**
579	+	* {@inheritDoc}
580	+	*/
581	+	public int hashCode() {
582	+	int expectedModCount = modCount;
583	+	int hash = hashCodeRange(0, size);
584	+	checkForComodification(expectedModCount);
585	+	return hash;
586	+	}
587	+
588	+	int hashCodeRange(int from, int to) {
589	+	final Object[] es = elementData;
590	+	if (to > es.length) {
591	+	throw new ConcurrentModificationException();
592	+	}
593	+	int hashCode = 1;
594	+	for (int i = from; i < to; i++) {
595	+	Object e = es[i];
596	+	hashCode = 31 * hashCode + (e == null ? 0 : e.hashCode());
597	+	}
598	+	return hashCode;
599	+	}
600	+
601	+	/**
602		* Removes the first occurrence of the specified element from this list,
603		* if it is present.  If the list does not contain the element, it is
604		* unchanged.  More formally, removes the element with the lowest index
#	Line 543 | Line 612 | public class ArrayList<E> extends Abstra
612		* @return {@code true} if this list contained the specified element
613		*/
614		public boolean remove(Object o) {
615	<	if (o == null) {
616	<	for (int index = 0; index < size; index++)
617	<	if (elementData[index] == null) {
618	<	fastRemove(index);
619	<	return true;
620	<	}
621	<	} else {
622	<	for (int index = 0; index < size; index++)
623	<	if (o.equals(elementData[index])) {
624	<	fastRemove(index);
625	<	return true;
626	<	}
615	>	final Object[] es = elementData;
616	>	final int size = this.size;
617	>	int i = 0;
618	>	found: {
619	>	if (o == null) {
620	>	for (; i < size; i++)
621	>	if (es[i] == null)
622	>	break found;
623	>	} else {
624	>	for (; i < size; i++)
625	>	if (o.equals(es[i]))
626	>	break found;
627	>	}
628	>	return false;
629		}
630	<	return false;
630	>	fastRemove(es, i);
631	>	return true;
632		}
633
634		/**
635		* Private remove method that skips bounds checking and does not
636		* return the value removed.
637		*/
638	<	private void fastRemove(int index) {
638	>	private void fastRemove(Object[] es, int i) {
639		modCount++;
640	<	int numMoved = size - index - 1;
641	<	if (numMoved > 0)
642	<	System.arraycopy(elementData, index+1, elementData, index,
643	<	numMoved);
572	<	elementData[--size] = null; // clear to let GC do its work
640	>	final int newSize;
641	>	if ((newSize = size - 1) > i)
642	>	System.arraycopy(es, i + 1, es, i, newSize - i);
643	>	es[size = newSize] = null;
644		}
645
646		/**
#	Line 748 | Line 819 | public class ArrayList<E> extends Abstra
819		final int from, final int end) {
820		Objects.requireNonNull(c);
821		final Object[] es = elementData;
751	–	final boolean modified;
822		int r;
823		// Optimize for initial run of survivors
824	<	for (r = from; r < end && c.contains(es[r]) == complement; r++)
825	<	;
826	<	if (modified = (r < end)) {
827	<	int w = r++;
828	<	try {
829	<	for (Object e; r < end; r++)
830	<	if (c.contains(e = es[r]) == complement)
831	<	es[w++] = e;
832	<	} catch (Throwable ex) {
833	<	// Preserve behavioral compatibility with AbstractCollection,
834	<	// even if c.contains() throws.
835	<	System.arraycopy(es, r, es, w, end - r);
836	<	w += end - r;
837	<	throw ex;
838	<	} finally {
839	<	modCount += end - w;
840	<	shiftTailOverGap(es, w, end);
841	<	}
824	>	for (r = from;; r++) {
825	>	if (r == end)
826	>	return false;
827	>	if (c.contains(es[r]) != complement)
828	>	break;
829	>	}
830	>	int w = r++;
831	>	try {
832	>	for (Object e; r < end; r++)
833	>	if (c.contains(e = es[r]) == complement)
834	>	es[w++] = e;
835	>	} catch (Throwable ex) {
836	>	// Preserve behavioral compatibility with AbstractCollection,
837	>	// even if c.contains() throws.
838	>	System.arraycopy(es, r, es, w, end - r);
839	>	w += end - r;
840	>	throw ex;
841	>	} finally {
842	>	modCount += end - w;
843	>	shiftTailOverGap(es, w, end);
844		}
845		// checkInvariants();
846	<	return modified;
846	>	return true;
847		}
848
849		/**
#	Line 784 | Line 856 | public class ArrayList<E> extends Abstra
856		*             instance is emitted (int), followed by all of its elements
857		*             (each an {@code Object}) in the proper order.
858		*/
859	+	// OPENJDK @java.io.Serial
860		private void writeObject(java.io.ObjectOutputStream s)
861		throws java.io.IOException {
862		// Write out element count, and any hidden stuff
863		int expectedModCount = modCount;
864		s.defaultWriteObject();
865
866	<	// Write out size as capacity for behavioural compatibility with clone()
866	>	// Write out size as capacity for behavioral compatibility with clone()
867		s.writeInt(size);
868
869		// Write out all elements in the proper order.
#	Line 811 | Line 884 | public class ArrayList<E> extends Abstra
884		*         could not be found
885		* @throws java.io.IOException if an I/O error occurs
886		*/
887	+	// OPENJDK @java.io.Serial
888		private void readObject(java.io.ObjectInputStream s)
889		throws java.io.IOException, ClassNotFoundException {
890
#	Line 822 | Line 896 | public class ArrayList<E> extends Abstra
896
897		if (size > 0) {
898		// like clone(), allocate array based upon size not capacity
899	+	jsr166.Platform.checkArray(s, Object[].class, size);
900		Object[] elements = new Object[size];
901
902		// Read in all elements in the proper order.
#	Line 1122 | Line 1197 | public class ArrayList<E> extends Abstra
1197		return true;
1198		}
1199
1200	+	public void replaceAll(UnaryOperator<E> operator) {
1201	+	root.replaceAllRange(operator, offset, offset + size);
1202	+	}
1203	+
1204		public boolean removeAll(Collection<?> c) {
1205		return batchRemove(c, false);
1206		}
#	Line 1149 | Line 1228 | public class ArrayList<E> extends Abstra
1228		return modified;
1229		}
1230
1231	+	public Object[] toArray() {
1232	+	checkForComodification();
1233	+	return Arrays.copyOfRange(root.elementData, offset, offset + size);
1234	+	}
1235	+
1236	+	@SuppressWarnings("unchecked")
1237	+	public <T> T[] toArray(T[] a) {
1238	+	checkForComodification();
1239	+	if (a.length < size)
1240	+	return (T[]) Arrays.copyOfRange(
1241	+	root.elementData, offset, offset + size, a.getClass());
1242	+	System.arraycopy(root.elementData, offset, a, 0, size);
1243	+	if (a.length > size)
1244	+	a[size] = null;
1245	+	return a;
1246	+	}
1247	+
1248	+	public boolean equals(Object o) {
1249	+	if (o == this) {
1250	+	return true;
1251	+	}
1252	+
1253	+	if (!(o instanceof List)) {
1254	+	return false;
1255	+	}
1256	+
1257	+	boolean equal = root.equalsRange((List<?>)o, offset, offset + size);
1258	+	checkForComodification();
1259	+	return equal;
1260	+	}
1261	+
1262	+	public int hashCode() {
1263	+	int hash = root.hashCodeRange(offset, offset + size);
1264	+	checkForComodification();
1265	+	return hash;
1266	+	}
1267	+
1268	+	public int indexOf(Object o) {
1269	+	int index = root.indexOfRange(o, offset, offset + size);
1270	+	checkForComodification();
1271	+	return index >= 0 ? index - offset : -1;
1272	+	}
1273	+
1274	+	public int lastIndexOf(Object o) {
1275	+	int index = root.lastIndexOfRange(o, offset, offset + size);
1276	+	checkForComodification();
1277	+	return index >= 0 ? index - offset : -1;
1278	+	}
1279	+
1280	+	public boolean contains(Object o) {
1281	+	return indexOf(o) >= 0;
1282	+	}
1283	+
1284		public Iterator<E> iterator() {
1285		return listIterator();
1286		}
#	Line 1556 | Line 1688 | public class ArrayList<E> extends Abstra
1688		setBit(deathRow, i - beg);
1689		if (modCount != expectedModCount)
1690		throw new ConcurrentModificationException();
1559	–	expectedModCount++;
1691		modCount++;
1692		int w = beg;
1693		for (i = beg; i < end; i++)
#	Line 1575 | Line 1706 | public class ArrayList<E> extends Abstra
1706
1707		@Override
1708		public void replaceAll(UnaryOperator<E> operator) {
1709	+	replaceAllRange(operator, 0, size);
1710	+	// TODO(8203662): remove increment of modCount from ...
1711	+	modCount++;
1712	+	}
1713	+
1714	+	private void replaceAllRange(UnaryOperator<E> operator, int i, int end) {
1715		Objects.requireNonNull(operator);
1716		final int expectedModCount = modCount;
1717		final Object[] es = elementData;
1718	<	final int size = this.size;
1582	<	for (int i = 0; modCount == expectedModCount && i < size; i++)
1718	>	for (; modCount == expectedModCount && i < end; i++)
1719		es[i] = operator.apply(elementAt(es, i));
1720		if (modCount != expectedModCount)
1721		throw new ConcurrentModificationException();
1586	–	modCount++;
1722		// checkInvariants();
1723		}
1724

Diff Legend

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