多線程之原子性對比demo

package com.thread.test;

import java.util.Random;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicInteger;

public class StaticIn
{
    public static void main(String[] args)
        throws InterruptedException
    {

        CountDownLatch begin = new CountDownLatch();


        CountDownLatch end = new CountDownLatch();


        ExecutorService exec = Executors.newFixedThreadPool();
        StaticIn ss = new StaticIn();
        for (int index = ; index < ; index++)
        {
            exec.submit(ss.new MyIn(begin, end));
        }
        System.out.println("Game Start");
        // begin減一，開始遊戲
        begin.countDown();
        // 等待end變為0，即所有線程到達終點
        end.await();
        System.out.println("Game Over");
        exec.shutdown();

        System.out.println("now count is : " + count);
        System.out.println("now sun is : " + sum);
    }

    static int count = ;
    static AtomicInteger sum=new AtomicInteger();
    class MyIn extends Thread
    {
        Random random = new Random();

        // 開始的倒數鎖
        CountDownLatch begin;

        // 結束的倒數鎖
        CountDownLatch end;

        public MyIn(CountDownLatch begin_, CountDownLatch end_)
        {
            this.begin = begin_;
            this.end = end_;

        }

        @Override
        public void run()
        {
            try
            {
                begin.await();
                Thread.sleep(random.nextInt());
                count++;
                sum.addAndGet();
            }
            catch (InterruptedException e)
            {
                e.printStackTrace();
            }
            finally
            {
                end.countDown();
            }
        }
    }

}