java并发编程学习之脏读代码示例及处理

来源：互联网发布：feynman 知乎编辑：程序博客网时间：2024/06/13 00:22

public class Thread10 {    public static void main(String[] args) {        Thread10_Entity entity = new Thread10_Entity();        Thread10_1 t10_1 = new  Thread10_1(entity);        t10_1.start();        try {            Thread.sleep(1000);        } catch (InterruptedException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        System.out.println(entity.get());    }}class Thread10_1 extends Thread {    private Thread10_Entity thread10_Entity;    public Thread10_1(Thread10_Entity t10) {        this.thread10_Entity = t10;    }    @Override    public void run() {        thread10_Entity.set("admin", "admin");    }}class Thread10_Entity {    private String username = "user";    private String password = "user";    synchronized void set(String username, String password) {        this.username = username;        try {            Thread.sleep(5000);        } catch (InterruptedException e) {            // TODO Auto-generated catch block            e.printStackTrace();        }        this.password = password;    }    String get() {        return username + "   " + password;    }}

运行结果：admin user

加上sleep只是为了放大错误，便于观察。
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那么如何避免脏读呢？上篇文章（ java并发编程学习之一段简单代码证明synchronized锁的是对象）中提到过，synchronized锁的是对象，这里就可以用上了。
在get方法上加上synchronized关键字即可，在set没处理完之前，对对象加锁，避免其他线程进行脏读。

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