ForkJoinPow

gistfile1.txt

package interview;

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

/**
 * Created by zhuguowei on 5/17/17.
 */
public class ForkJoinPow extends RecursiveTask<Long> {
    private int a;
    private int b;

    public ForkJoinPow(int a, int b) {
        this.a = a;
        this.b = b;
    }
    @Override
    protected Long compute() {
//        System.out.printf("%s %d%n",Thread.currentThread().getName(),b);
        if(b == 1){
            return Long.valueOf(a);
        }
//        if(b == 2){
//            return Long.valueOf(a * a);
//        }
        int left = b/2;
        ForkJoinPow leftResult = new ForkJoinPow(a, left);
        leftResult.fork();
        ForkJoinPow rightResult = new ForkJoinPow(a, b - left);

        return rightResult.compute() * leftResult.join();
    }

    public static void main(String[] args) {
        int a = 2;
        int b = 30;
        ForkJoinPow task = new ForkJoinPow(a, b);
        ForkJoinPool pool = new ForkJoinPool();
        Long result = pool.invoke(task);
        System.out.println(result);
    }
}