forkjoin练习

package com.gxnu.bigdata.study.forkjoin;

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

import org.junit.Test;

public class  {
	public class Calculator extends RecursiveTask<Integer> {
		private static final int THRESHOLD = 100;
		private int start;
		private int end;

		public Calculator(int start, int end) {
			this.start = start;
			this.end = end;
		}

		
		protected Integer compute() {
			int sum = 0;
			if ((start - end) < THRESHOLD) {
				for (int i = start; i < end; i++) {
					sum += i;
				}
			} else {
				int middle = (start + end) / 2;
				Calculator left = new Calculator(start, middle);
				Calculator right = new Calculator(middle + 1, end);
				left.fork();
				right.fork();

				sum = left.join() + right.join();
			}
			return sum;
		}
	}

	@Test
	public void test() {
		Calculator calculator = new Calculator(110, 100);
		int compute = calculator.compute();
		System.out.println(compute);
	}

	@Test
	public void run() throws Exception {
		ForkJoinPool forkJoinPool = new ForkJoinPool();
		Future<Integer> result = forkJoinPool.submit(new Calculator(0, 10000));

		
		 * if(result.isDone()){ System.out.println(result.get()); }
		 */
		Random random = new Random();
		int num = random.nextInt(100);
		if (!result.isDone()) {
			Thread.sleep(num);
			System.out.println(result.get());
		}
		// assertEquals(new Integer(49995000), result.get());
	}
}