java 数值实验并行计算（并行计算框架ForkJoin）

代码

import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.concurrent.ForkJoinPool;
public class ParallelTest {
    public static void main(String[] args) {
        System.out.println("线程数为"+ForkJoinPool.getCommonPoolParallelism());
        for(int j=0; j<10; j++){
            List<Integer> result = new ArrayList<>();
            //测试forkjoin耗时
            List<Integer> list = new ArrayList<>();
            for (int i = 0; i < 20; i++) {
                list.add(i);
            }
            long s = System.currentTimeMillis();
            Random random = new Random();
            list.parallelStream().forEach(i -> {
                try {
                    result.add(i);
                    int time = random.nextInt(100);
                    System.out.println("等待时间为: " + time);
                    Thread.sleep(time);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            });
            long e = System.currentTimeMillis();
            System.out.print(j + ": forkjoin:" + (e - s));
            System.out.print("\t list的长度为：" + list.size());
            System.out.print("\t result的长度为：" + result.size());
            System.out.println("");
        }
//        for(int i=0; i<result.size(); i++){
//            System.out.printf("第%d个元素的值为%d\n", i, result.get(i));
//        }
    }
}

参考资料

• Java并行计算框架之ForkJoin