package lock;

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

//分支合併
class MyTask extends RecursiveTask<Integer>{
    //拆分差值不超過10
    private static final Integer number = 10;
    
 
private int begin;//拆分開始值
    private int end;//拆分結束值
    private int result;//返回結果

    //建立有參構造
    public MyTask(int begin,int end){
        this.begin=begin;
        this.end=end;
    }
    //拆分和合並過程
    @Override
    protected Integer compute() {
        //判斷差值是否大於10 小於直接相加
        if (end-begin>=number){
            
 
//相加操作
            for (int i = begin; i <= end ; i++) {
                result = result+i;
            }
        }else {//進一步拆分
            //獲取資料中間值
            int middle = (begin+end)/2;
            //拆分左邊
            MyTask task01 = new MyTask(begin,middle);
            //拆分右邊
            MyTask task02 = new
 
 MyTask(middle,end);
            //呼叫方法拆分
            task01.fork();
            task02.fork();
            //合併結果
            result = task01.join() + task02.join();
        }
        return result;
    }
}
public class Lock_10 {
    public static void main(String[] args) throws ExecutionException, InterruptedException {
        //建立MyTask物件
        MyTask myTask = new MyTask(0,100);
        //建立分支合併池物件
        ForkJoinPool forkJoinPool = new ForkJoinPool();
        ForkJoinTask<Integer> forkJoinTask = forkJoinPool.submit(myTask);
        //獲取最終合併之後結果
        Integer integer = forkJoinTask.get();
        System.out.println(integer);
        //關閉池物件
        forkJoinPool.shutdown();

    }
}

　　fork是分支

　　join是合併