forkjoinpool

public static void main(String[] args) {
        ForkJoinTask<Long> myForkJoinPool = new MyForkJoinPool(1L,999999999L);

        ForkJoinPool pool = ForkJoinPool.commonPool();
        Future<Long> future = pool.submit(myForkJoinPool); //提交分解的SumTask 任务
        try {
            System.out.println(future.get());
        }  catch (Exception e) {
            e.printStackTrace();
        }


    }

 

import java.util.concurrent.RecursiveTask;

/**
 * @author shiqil.liu
 * @date 2019-08-23 16:31
 */
public class MyForkJoinPool extends RecursiveTask<Long> {
    private long start;
    private long end;
    public static final long MAX_SIZE = 10000;

    public MyForkJoinPool(long start, long end) {
        this.start = start;
        this.end = end;
    }

    public long getStart() {
        return start;
    }

    public void setStart(long start) {
        this.start = start;
    }

    public long getEnd() {
        return end;
    }

    public void setEnd(long end) {
        this.end = end;
    }



    @Override
    protected Long compute() {
        long sum = 0;
        if(end -start < MAX_SIZE) {
            for(long i=start;i<=end;i++) {
                sum += i;
            }
            return sum;
        } else {
            long mid = (end+start) / 2 ;
            MyForkJoinPool myForkJoinPool1 = new MyForkJoinPool(start, mid);
            MyForkJoinPool myForkJoinPool2 = new MyForkJoinPool(mid+1, end);
            //invokeAll(myForkJoinPool1,myForkJoinPool1);
            myForkJoinPool1.fork();
            myForkJoinPool2.fork();
            return myForkJoinPool1.join()+myForkJoinPool2.join();
        }

    }


}