--- jsr166/src/main/java/util/PriorityQueue.java 2016/11/30 18:12:52 1.114
+++ jsr166/src/main/java/util/PriorityQueue.java 2018/05/06 16:26:03 1.123
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -26,6 +26,7 @@
package java.util;
import java.util.function.Consumer;
+import jdk.internal.misc.SharedSecrets;
/**
* An unbounded priority {@linkplain Queue queue} based on a priority heap.
@@ -73,7 +74,7 @@ import java.util.function.Consumer;
* ({@code peek}, {@code element}, and {@code size}).
*
*
This class is a member of the
- *
+ *
* Java Collections Framework.
*
* @since 1.5
@@ -350,8 +351,9 @@ public class PriorityQueue extends Ab
private int indexOf(Object o) {
if (o != null) {
- for (int i = 0; i < size; i++)
- if (o.equals(queue[i]))
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++)
+ if (o.equals(es[i]))
return i;
}
return -1;
@@ -379,20 +381,18 @@ public class PriorityQueue extends Ab
}
/**
- * Version of remove using reference equality, not equals.
- * Needed by iterator.remove.
+ * Identity-based version for use in Itr.remove.
*
* @param o element to be removed from this queue, if present
- * @return {@code true} if removed
*/
- boolean removeEq(Object o) {
- for (int i = 0; i < size; i++) {
- if (o == queue[i]) {
+ void removeEq(Object o) {
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++) {
+ if (o == es[i]) {
removeAt(i);
- return true;
+ break;
}
}
- return false;
}
/**
@@ -522,6 +522,8 @@ public class PriorityQueue extends Ab
*/
private int expectedModCount = modCount;
+ Itr() {} // prevent access constructor creation
+
public boolean hasNext() {
return cursor < size ||
(forgetMeNot != null && !forgetMeNot.isEmpty());
@@ -575,8 +577,9 @@ public class PriorityQueue extends Ab
*/
public void clear() {
modCount++;
- for (int i = 0; i < size; i++)
- queue[i] = null;
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++)
+ es[i] = null;
size = 0;
}
@@ -631,7 +634,7 @@ public class PriorityQueue extends Ab
* promoting x up the tree until it is greater than or equal to
* its parent, or is the root.
*
- * To simplify and speed up coercions and comparisons. the
+ * To simplify and speed up coercions and comparisons, the
* Comparable and Comparator versions are separated into different
* methods that are otherwise identical. (Similarly for siftDown.)
*
@@ -732,12 +735,12 @@ public class PriorityQueue extends Ab
@SuppressWarnings("unchecked")
private void heapify() {
final Object[] es = queue;
- final int half = (size >>> 1) - 1;
+ int i = (size >>> 1) - 1;
if (comparator == null)
- for (int i = half; i >= 0; i--)
+ for (; i >= 0; i--)
siftDownComparable(i, (E) es[i]);
else
- for (int i = half; i >= 0; i--)
+ for (; i >= 0; i--)
siftDownUsingComparator(i, (E) es[i]);
}
@@ -772,8 +775,9 @@ public class PriorityQueue extends Ab
s.writeInt(Math.max(2, size + 1));
// Write out all elements in the "proper order".
- for (int i = 0; i < size; i++)
- s.writeObject(queue[i]);
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++)
+ s.writeObject(es[i]);
}
/**
@@ -793,11 +797,13 @@ public class PriorityQueue extends Ab
// Read in (and discard) array length
s.readInt();
+ SharedSecrets.getJavaObjectInputStreamAccess().checkArray(s, Object[].class, size);
queue = new Object[size];
// Read in all elements.
- for (int i = 0; i < size; i++)
- queue[i] = s.readObject();
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++)
+ es[i] = s.readObject();
// Elements are guaranteed to be in "proper order", but the
// spec has never explained what that might be.
@@ -823,10 +829,6 @@ public class PriorityQueue extends Ab
}
final class PriorityQueueSpliterator implements Spliterator {
- /*
- * This is very similar to ArrayList Spliterator, except for
- * extra null checks.
- */
private int index; // current index, modified on advance/split
private int fence; // -1 until first use
private int expectedModCount; // initialized when fence set
@@ -855,46 +857,33 @@ public class PriorityQueue extends Ab
@SuppressWarnings("unchecked")
public void forEachRemaining(Consumer super E> action) {
- int i, hi, mc; // hoist accesses and checks from loop
- final Object[] a;
if (action == null)
throw new NullPointerException();
- if ((a = queue) != null) {
- if ((hi = fence) < 0) {
- mc = modCount;
- hi = size;
- }
- else
- mc = expectedModCount;
- if ((i = index) >= 0 && (index = hi) <= a.length) {
- for (E e;; ++i) {
- if (i < hi) {
- if ((e = (E) a[i]) == null) // must be CME
- break;
- action.accept(e);
- }
- else if (modCount != mc)
- break;
- else
- return;
- }
- }
+ if (fence < 0) { fence = size; expectedModCount = modCount; }
+ final Object[] a = queue;
+ int i, hi; E e;
+ for (i = index, index = hi = fence; i < hi; i++) {
+ if ((e = (E) a[i]) == null)
+ break; // must be CME
+ action.accept(e);
}
- throw new ConcurrentModificationException();
+ if (modCount != expectedModCount)
+ throw new ConcurrentModificationException();
}
+ @SuppressWarnings("unchecked")
public boolean tryAdvance(Consumer super E> action) {
if (action == null)
throw new NullPointerException();
- int hi = getFence(), lo = index;
- if (lo >= 0 && lo < hi) {
- index = lo + 1;
- @SuppressWarnings("unchecked") E e = (E)queue[lo];
- if (e == null)
+ if (fence < 0) { fence = size; expectedModCount = modCount; }
+ int i;
+ if ((i = index) < fence) {
+ index = i + 1;
+ E e;
+ if ((e = (E) queue[i]) == null
+ || modCount != expectedModCount)
throw new ConcurrentModificationException();
action.accept(e);
- if (modCount != expectedModCount)
- throw new ConcurrentModificationException();
return true;
}
return false;
@@ -908,4 +897,18 @@ public class PriorityQueue extends Ab
return Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.NONNULL;
}
}
+
+ /**
+ * @throws NullPointerException {@inheritDoc}
+ */
+ @SuppressWarnings("unchecked")
+ public void forEach(Consumer super E> action) {
+ Objects.requireNonNull(action);
+ final int expectedModCount = modCount;
+ final Object[] es = queue;
+ for (int i = 0, n = size; i < n; i++)
+ action.accept((E) es[i]);
+ if (expectedModCount != modCount)
+ throw new ConcurrentModificationException();
+ }
}