ForkJoinPoolet用于类似递归

package cn.temp.temp;

import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.RecursiveTask;

// F:\myeclipseWorker\temp\bin\cn\temp\temp
// java -classpath .; cn.temp.temp.Temp
// java -classpath . cn.temp.temp.Temp
public class Temp {

    public static void main(String[] args) throws Exception {
        long start;
        int count = 20;
        
        start = System.currentTimeMillis();
        int value = a(count);
        System.out.println(value);
        System.out.println("用时：" + (System.currentTimeMillis() - start) + " ms");

        start = System.currentTimeMillis();
        ForkJoinPool pool = new ForkJoinPool();
        Task task = new Task(count);
        pool.invoke(task);
        System.out.println(task.getRawResult());
        System.out.println("用时：" + (System.currentTimeMillis() - start) + " ms");
    }

    public static int a(int j) {
        if (j <= 2)
            return 1;
        return a(j - 2) + a(j - 1);
    }
}

@SuppressWarnings("serial")
class Task extends RecursiveTask<Integer> {
    int    i;

    Task(int i) {
        super();
        this.i = i;
    }

    @Override
    protected Integer compute() {
        if (i <= 2)
            return 1;
        Task t1 = new Task(i - 1);
        Task t2 = new Task(i - 2);
        invokeAll(t1, t2);
        return t1.getRawResult() + t2.getRawResult();
    }

}