forkjoin多线程执行任务

ForkJoin.java

package com.doraemoney.wk.quotecheckplatform.util;

import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.RecursiveAction;
import java.util.concurrent.TimeUnit;

/**
 * created by wanglichao@163.com on 2018/10/26.
 */
public class PrintTask extends RecursiveAction{
    // 每个"小任务"最多只打印20个数
    private static final int MAX = 50;

    private int start;
    private int end;

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

    @Override
    protected void compute() {
        // 当end-start的值小于MAX时候，开始打印
        if ((end - start) < MAX) {
            for (int i = start; i < end; i++) {
                System.out.println(Thread.currentThread().getName() + "的i值:"
                        + i);
            }
        } else {
            // 将大任务分解成两个小任务
            int middle = (start + end) / 2;
            System.out.println("进入分解任务start："+start+",middle:"+middle+",end:"+end);
            PrintTask left = new PrintTask(start, middle);
            PrintTask right = new PrintTask(middle, end);
            // 并行执行两个小任务
            invokeAll(left,right);
        }
    }
    public static void main(String[] args) throws Exception {
        // 创建包含Runtime.getRuntime().availableProcessors()返回值作为个数的并行线程的ForkJoinPool
        ForkJoinPool forkJoinPool = new ForkJoinPool();//todo使用线程池
        // 提交可分解的PrintTask任务
        forkJoinPool.submit(new PrintTask(0, 1000));
        forkJoinPool.awaitTermination(2, TimeUnit.SECONDS);//阻塞当前线程直到 ForkJoinPool 中所有的任务都执行结束
        // 关闭线程池
        forkJoinPool.shutdown();
    }

}