浅谈辄止_java forkjoinpool

package com.muyichen.demo.forkjoin;
import lombok.extern.slf4j.Slf4j;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.Future;
import java.util.concurrent.RecursiveTask;
@Slf4j
public class ForkJoinExample extends RecursiveTask<Integer> { 

public static final int threshold = 2;
private int start;
private int end;
public ForkJoinExample(int start, int end) { 

this.start = start;
this.end = end;
}
@Override
protected Integer compute() { 

int sum = 0;
//如果任务足够小就计算任务
boolean canCompute = (end - start) <= threshold;
if (canCompute) { 

for (int i = start; i <= end; i++) { 

sum += i;
}
} else { 

// 如果任务大于阈值，就分裂成两个子任务计算
int middle = (start + end) / 2;
ForkJoinExample leftTask = new ForkJoinExample(start, middle);
ForkJoinExample rightTask = new ForkJoinExample(middle + 1, end);
// 执行子任务
leftTask.fork();
rightTask.fork();
// 等待任务执行结束合并其结果
int leftResult = leftTask.join();
int rightResult = rightTask.join();
// 合并子任务
sum = leftResult + rightResult;
}
return sum;
}
public static void main(String[] args) { 

ForkJoinPool forkjoinPool = new ForkJoinPool();
//生成一个计算任务，计算1加到100
ForkJoinExample task = new ForkJoinExample(1, 100);
//执行一个任务
Future<Integer> result = forkjoinPool.submit(task);
try { 

log.info("result:{}", result.get());
} catch (Exception e) { 

log.error("exception", e);
}
}
}