Fork/Jion框架详解

public class ForkJionDemo extends RecursiveTask<Integer> {    //任务拆分阈值    public static final int threshold = 100;    //计算起始值    private int start;    //计算结束值    private int end;
    public ForkJionDemo(int start, int end) {        this.start = start;        this.end = end;    }
    @Override    protected Integer compute() {        int sum = 0;        //计算任务是否需要拆分        boolean canCompute = (end - start) <= threshold;        if (canCompute) {            //无需拆分则执行任务累计            for (int i = start; i <= end; i++) {                sum += i;            }        } else {            List<ForkJionDemo> forkJionDemoList=new ArrayList<>();            //将任务拆分成100份            for(int i=0;i<100;i++){                //计算这个一份任务要计算的起点和终点，如果终点大于最大值则使用最大值为终点                int last=(start+threshold)>end?end:(start+threshold);                ForkJionDemo forkJionDemo = new ForkJionDemo(start, last);                //下一份任务的起点要更新                start+=threshold+1;                forkJionDemoList.add(forkJionDemo);                //提交子任务                forkJionDemo.fork();            }            //汇总拆分完毕后的任务结果            for(ForkJionDemo forkJionDemo:forkJionDemoList){                sum  += forkJionDemo.join();            }        }        return sum;    }
    public static void main(String[] args) {        //构造一个任务线程池        ForkJoinPool forkjoinPool = new ForkJoinPool();        //创建一个计算1到10000之间所有数的和的任务        ForkJionDemo forkJionDemo = new ForkJionDemo(1, 10000);        //将任务提交到任务线程池        Future<Integer> result = forkjoinPool.submit(forkJionDemo);        try {            //打印最后计算结果            System.out.println(result.get());        } catch (InterruptedException e) {            e.printStackTrace();        } catch (ExecutionException e) {            e.printStackTrace();        }    }}