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root/jsr166/jsr166/src/jsr166y/RecursiveAction.java
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Comparing jsr166/src/jsr166y/RecursiveAction.java (file contents):
Revision 1.5 by jsr166, Mon Jul 20 23:07:43 2009 UTC vs.
Revision 1.11 by dl, Tue Aug 4 14:42:02 2009 UTC

# Line 7 | Line 7
7   package jsr166y;
8  
9   /**
10 < * Recursive resultless ForkJoinTasks. This class establishes
11 < * conventions to parameterize resultless actions as {@code Void}
12 < * ForkJoinTasks. Because {@code null} is the only valid value of
13 < * type {@code Void}, methods such as join always return {@code null}
14 < * upon completion.
10 > * A recursive resultless {@link ForkJoinTask}.  This class
11 > * establishes conventions to parameterize resultless actions as
12 > * {@code Void} {@code ForkJoinTask}s. Because {@code null} is the
13 > * only valid value of type {@code Void}, methods such as join always
14 > * return {@code null} upon completion.
15   *
16   * <p><b>Sample Usages.</b> Here is a sketch of a ForkJoin sort that
17   * sorts a given {@code long[]} array:
# Line 34 | Line 34 | package jsr166y;
34   *   }
35   * }}</pre>
36   *
37 < * You could then sort anArray by creating {@code new SortTask(anArray, 0,
38 < * anArray.length-1) } and invoking it in a ForkJoinPool.
39 < * As a more concrete simple example, the following task increments
40 < * each element of an array:
37 > * You could then sort {@code anArray} by creating {@code new
38 > * SortTask(anArray, 0, anArray.length-1) } and invoking it in a
39 > * ForkJoinPool.  As a more concrete simple example, the following
40 > * task increments each element of an array:
41   *  <pre> {@code
42   * class IncrementTask extends RecursiveAction {
43   *   final long[] array; final int lo; final int hi;
# Line 64 | Line 64 | package jsr166y;
64   * of each element of a double array, by subdividing out only the
65   * right-hand-sides of repeated divisions by two, and keeping track of
66   * them with a chain of {@code next} references. It uses a dynamic
67 < * threshold based on method {@code surplus}, but counterbalances
68 < * potential excess partitioning by directly performing leaf actions
69 < * on unstolen tasks rather than further subdividing.
67 > * threshold based on method {@code getEstimatedSurplusTaskCount}, but
68 > * counterbalances potential excess partitioning by directly
69 > * performing leaf actions on unstolen tasks rather than further
70 > * subdividing.
71   *
72   *  <pre> {@code
73   * double sumOfSquares(ForkJoinPool pool, double[] array) {
# Line 98 | Line 99 | package jsr166y;
99   *     int l = lo;
100   *     int h = hi;
101   *     Applyer right = null;
102 < *     while (h - l > 1 &&
102 < *        ForkJoinWorkerThread.getEstimatedSurplusTaskCount() <= 3) {
102 > *     while (h - l > 1 && getSurplusQueuedTaskCount() <= 3) {
103   *        int mid = (l + h) >>> 1;
104   *        right = new Applyer(array, mid, h, seqSize, right);
105   *        right.fork();
# Line 118 | Line 118 | package jsr166y;
118   *     result = sum;
119   *   }
120   * }}</pre>
121 + *
122 + * @since 1.7
123 + * @author Doug Lea
124   */
125   public abstract class RecursiveAction extends ForkJoinTask<Void> {
126 +    private static final long serialVersionUID = 5232453952276485070L;
127  
128      /**
129       * The main computation performed by this task.

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