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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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package jsr166y; |
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/** |
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* Recursive result-bearing ForkJoinTasks. |
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* <p> For a classic example, here is a task computing Fibonacci numbers: |
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* A recursive result-bearing {@link ForkJoinTask}. |
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* |
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* <p>For a classic example, here is a task computing Fibonacci numbers: |
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* |
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* <pre> {@code |
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* class Fibonacci extends RecursiveTask<Integer> { |
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* final int n; |
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* Fibonacci(int n) { this.n = n; } |
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* Integer compute() { |
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* protected Integer compute() { |
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* if (n <= 1) |
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* return n; |
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* return n; |
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* Fibonacci f1 = new Fibonacci(n - 1); |
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* f1.fork(); |
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* Fibonacci f2 = new Fibonacci(n - 2); |
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* @author Doug Lea |
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*/ |
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public abstract class RecursiveTask<V> extends ForkJoinTask<V> { |
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private static final long serialVersionUID = 5232453952276485270L; |
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/** |
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* Empty constructor for use by subclasses. |
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*/ |
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protected RecursiveTask() { |
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} |
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/** |
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* The result returned by compute method. |
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* The result of the computation. |
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*/ |
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V result; |
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} |
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/** |
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* Implements execution conventions for RecursiveTask |
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* Implements execution conventions for RecursiveTask. |
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*/ |
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protected final boolean exec() { |
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result = compute(); |