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Comparing jsr166/src/main/java/util/ArrayList.java (file contents):
Revision 1.45 by jsr166, Wed Nov 30 03:31:47 2016 UTC vs.
Revision 1.68 by jsr166, Sat Aug 10 16:48:05 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 218 | Line 220 | public class ArrayList<E> extends Abstra
220		}
221
222		/**
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	–	/**
223		* Increases the capacity to ensure that it can hold at least the
224		* number of elements specified by the minimum capacity argument.
225		*
#	Line 233 | Line 227 | public class ArrayList<E> extends Abstra
227		* @throws OutOfMemoryError if minCapacity is less than zero
228		*/
229		private Object[] grow(int minCapacity) {
230	<	return elementData = Arrays.copyOf(elementData,
231	<	newCapacity(minCapacity));
230	>	int oldCapacity = elementData.length;
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() {
#	Line 242 | Line 243 | public class ArrayList<E> extends Abstra
243		}
244
245		/**
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	–	/**
246		* Returns the number of elements in this list.
247		*
248		* @return the number of elements in this list
#	Line 313 | Line 281 | public class ArrayList<E> extends Abstra
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 333 | Line 310 | public class ArrayList<E> extends Abstra
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		}
#	Line 515 | Line 501 | public class ArrayList<E> extends Abstra
501		*/
502		public E remove(int index) {
503		Objects.checkIndex(index, size);
504	+	final Object[] es = elementData;
505
506	<	modCount++;
507	<	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
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
#	Line 543 | Line 611 | public class ArrayList<E> extends Abstra
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		/**
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);
572	<	elementData[--size] = null; // clear to 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 578 | Line 648 | public class ArrayList<E> extends Abstra
648		*/
649		public void clear() {
650		modCount++;
651	<	Arrays.fill(elementData, 0, size, null);
652	<	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 669 | Line 740 | public class ArrayList<E> extends Abstra
740		outOfBoundsMsg(fromIndex, toIndex));
741		}
742		modCount++;
743	<	final Object[] es = elementData;
673	<	final int oldSize = size;
674	<	System.arraycopy(es, toIndex, es, fromIndex, oldSize - toIndex);
675	<	Arrays.fill(es, size -= (toIndex - fromIndex), oldSize, null);
743	>	shiftTailOverGap(elementData, fromIndex, toIndex);
744		// checkInvariants();
745		}
746
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		/**
755		* A version of rangeCheck used by add and addAll.
756		*/
#	Line 743 | Line 818 | public class ArrayList<E> extends Abstra
818		final int from, final int end) {
819		Objects.requireNonNull(c);
820		final Object[] es = elementData;
746	–	final boolean modified;
821		int r;
822		// Optimize for initial run of survivors
823	<	for (r = from; r < end && c.contains(es[r]) == complement; r++)
824	<	;
825	<	if (modified = (r < end)) {
826	<	int w = r++;
827	<	try {
828	<	for (Object e; r < end; r++)
829	<	if (c.contains(e = es[r]) == complement)
830	<	es[w++] = e;
831	<	} catch (Throwable ex) {
832	<	// Preserve behavioral compatibility with AbstractCollection,
833	<	// even if c.contains() throws.
834	<	System.arraycopy(es, r, es, w, end - r);
835	<	w += end - r;
836	<	throw ex;
837	<	} finally {
838	<	final int oldSize = size, deleted = end - w;
839	<	modCount += deleted;
840	<	System.arraycopy(es, end, es, w, oldSize - end);
841	<	Arrays.fill(es, size -= deleted, oldSize, null);
842	<	}
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 (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	>	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		// checkInvariants();
845	<	return modified;
845	>	return true;
846		}
847
848		/**
849	<	* Save the state of the {@code ArrayList} 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	+	* @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 {@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 size as capacity for behavioural compatibility with clone()
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.
#	Line 799 | Line 875 | public class ArrayList<E> extends Abstra
875		}
876
877		/**
878	<	* Reconstitute the {@code ArrayList} 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 {
#	Line 813 | Line 893 | public class ArrayList<E> extends Abstra
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.
#	Line 1113 | Line 1194 | public class ArrayList<E> extends Abstra
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		}
#	Line 1140 | Line 1225 | public class ArrayList<E> extends Abstra
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		}
#	Line 1362 | Line 1500 | public class ArrayList<E> extends Abstra
1500		}
1501		}
1502
1503	+	/**
1504	+	* @throws NullPointerException {@inheritDoc}
1505	+	*/
1506		@Override
1507		public void forEach(Consumer<? super E> action) {
1508		Objects.requireNonNull(action);
#	Line 1431 | Line 1572 | public class ArrayList<E> extends Abstra
1572		private int fence; // -1 until used; then one past last index
1573		private int expectedModCount; // initialized when fence set
1574
1575	<	/** Create new spliterator covering the given range */
1575	>	/** Creates new spliterator covering the given range. */
1576		ArrayListSpliterator(int origin, int fence, int expectedModCount) {
1577		this.index = origin;
1578		this.fence = fence;
#	Line 1513 | Line 1654 | public class ArrayList<E> extends Abstra
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);
#	Line 1541 | Line 1685 | public class ArrayList<E> extends Abstra
1685		setBit(deathRow, i - beg);
1686		if (modCount != expectedModCount)
1687		throw new ConcurrentModificationException();
1544	–	expectedModCount++;
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	<	final int oldSize = size;
1551	<	System.arraycopy(es, end, es, w, oldSize - end);
1552	<	Arrays.fill(es, size -= (end - w), oldSize, null);
1693	>	shiftTailOverGap(es, w, end);
1694		// checkInvariants();
1695		return true;
1696		} else {
#	Line 1562 | Line 1703 | public class ArrayList<E> extends Abstra
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	<	final int size = this.size;
1569	<	for (int i = 0; modCount == expectedModCount && i < size; i++)
1715	>	for (; modCount == expectedModCount && i < end; i++)
1716		es[i] = operator.apply(elementAt(es, i));
1717		if (modCount != expectedModCount)
1718		throw new ConcurrentModificationException();
1573	–	modCount++;
1719		// checkInvariants();
1720		}
1721

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