java 线程篇之 Atomic*

1、Atomic*是什么

java 提供了很多原子类来保证并发下的正确性和提升并发能力

2、Atomic*的用法

Atomic* 类提供的方法基本类似，我就挑出AtomicInteger来说明

public class AtomicTest {
    private static final AtomicInteger count = new AtomicInteger();
    private static final CountDownLatch start = new CountDownLatch(1);
    private static final CountDownLatch end = new CountDownLatch(10);
    private static final Object obj = new Object();

    public static void main(String[] args) throws InterruptedException {
        for (int i =0 ;i < 100 ;i++){
            Thread thread = new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        start.await();
                        //task
                        System.out.println("原子类在并发情况下的输出："+count.addAndGet(1));
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }finally {
                        end.countDown();
                    }
                }
            });
            thread.start();
        }
        start.countDown();
        end.await();
    }

上面输出结果不是顺序性（但是结果不会出现重复记录，由于存在字符串拼接）

 

转载于:https://my.oschina.net/chenping12/blog/1517507