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root/jsr166/jsr166/src/jsr166y/RecursiveTask.java

Comparing jsr166/src/jsr166y/RecursiveTask.java (file contents):
Revision 1.1 by dl, Tue Jan 6 14:30:31 2009 UTC vs.
Revision 1.5 by jsr166, Wed Jul 22 01:36:51 2009 UTC

#	Line 10 | Line 10 | package jsr166y;
10		* Recursive result-bearing ForkJoinTasks.
11		* <p> For a classic example, here is a task computing Fibonacci numbers:
12		*
13	<	* <pre>
14	<	* class Fibonacci extends RecursiveTask&lt;Integer&gt; {
13	>	*  <pre> {@code
14	>	* class Fibonacci extends RecursiveTask<Integer> {
15		*   final int n;
16	<	*   Fibonnaci(int n) { this.n = n; }
16	>	*   Fibonacci(int n) { this.n = n; }
17		*   Integer compute() {
18	<	*     if (n &lt;= 1)
18	>	*     if (n <= 1)
19		*        return n;
20		*     Fibonacci f1 = new Fibonacci(n - 1);
21		*     f1.fork();
22		*     Fibonacci f2 = new Fibonacci(n - 2);
23		*     return f2.compute() + f1.join();
24		*   }
25	<	* }
26	<	* </pre>
25	>	* }}</pre>
26		*
27		* However, besides being a dumb way to compute Fibonacci functions
28		* (there is a simple fast linear algorithm that you'd use in
#	Line 31 | Line 30 | package jsr166y;
30		* subtasks are too small to be worthwhile splitting up. Instead, as
31		* is the case for nearly all fork/join applications, you'd pick some
32		* minimum granularity size (for example 10 here) for which you always
33	<	* sequentially solve rather than subdividing.
33	>	* sequentially solve rather than subdividing.
34		*
35	+	* @since 1.7
36	+	* @author Doug Lea
37		*/
38		public abstract class RecursiveTask<V> extends ForkJoinTask<V> {
39
40		/**
41	<	* Empty contructor for use by subclasses.
41	>	* Empty constructor for use by subclasses.
42		*/
43		protected RecursiveTask() {
44		}
#	Line 48 | Line 49 | public abstract class RecursiveTask<V> e
49		V result;
50
51		/**
52	<	* The main computation performed by this task.
52	>	* The main computation performed by this task.
53		*/
54		protected abstract V compute();
55

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