--- jsr166/src/main/java/util/ArrayList.java 2016/12/08 05:02:32 1.48
+++ jsr166/src/main/java/util/ArrayList.java 2017/05/14 21:44:25 1.51
@@ -91,7 +91,7 @@ import java.util.function.UnaryOperator;
* should be used only to detect bugs.
*
*
This class is a member of the
- *
+ *
* Java Collections Framework.
*
* @param the type of elements in this list
@@ -515,15 +515,10 @@ public class ArrayList extends Abstra
*/
public E remove(int index) {
Objects.checkIndex(index, size);
+ final Object[] es = elementData;
- modCount++;
- E oldValue = elementData(index);
-
- int numMoved = size - index - 1;
- if (numMoved > 0)
- System.arraycopy(elementData, index+1, elementData, index,
- numMoved);
- elementData[--size] = null; // clear to let GC do its work
+ @SuppressWarnings("unchecked") E oldValue = (E) es[index];
+ fastRemove(es, index);
// checkInvariants();
return oldValue;
@@ -543,33 +538,35 @@ public class ArrayList extends Abstra
* @return {@code true} if this list contained the specified element
*/
public boolean remove(Object o) {
- if (o == null) {
- for (int index = 0; index < size; index++)
- if (elementData[index] == null) {
- fastRemove(index);
- return true;
- }
- } else {
- for (int index = 0; index < size; index++)
- if (o.equals(elementData[index])) {
- fastRemove(index);
- return true;
- }
+ final Object[] es = elementData;
+ final int size = this.size;
+ int i = 0;
+ found: {
+ if (o == null) {
+ for (; i < size; i++)
+ if (es[i] == null)
+ break found;
+ } else {
+ for (; i < size; i++)
+ if (o.equals(es[i]))
+ break found;
+ }
+ return false;
}
- return false;
+ fastRemove(es, i);
+ return true;
}
/**
* Private remove method that skips bounds checking and does not
* return the value removed.
*/
- private void fastRemove(int index) {
+ private void fastRemove(Object[] es, int i) {
modCount++;
- int numMoved = size - index - 1;
- if (numMoved > 0)
- System.arraycopy(elementData, index+1, elementData, index,
- numMoved);
- elementData[--size] = null; // clear to let GC do its work
+ final int newSize;
+ if ((newSize = size - 1) > i)
+ System.arraycopy(es, i + 1, es, i, newSize - i);
+ es[size = newSize] = null;
}
/**
@@ -1443,7 +1440,7 @@ public class ArrayList extends Abstra
private int fence; // -1 until used; then one past last index
private int expectedModCount; // initialized when fence set
- /** Create new spliterator covering the given range */
+ /** Creates new spliterator covering the given range. */
ArrayListSpliterator(int origin, int fence, int expectedModCount) {
this.index = origin;
this.fence = fence;