彻底搞懂对象并发访问（六）

最新推荐文章于 2024-06-28 13:33:28 发布

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最新推荐文章于 2024-06-28 13:33:28 发布

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分类专栏：多线程文章标签：多线程

本文链接：https://blog.youkuaiyun.com/weixin_37418246/article/details/89212643

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12 篇文章

订阅专栏

本文深入探讨了Java中多线程与同步机制的关系，通过具体示例代码讲解了对象锁与Class锁的区别及作用范围，揭示了多线程环境下不同锁导致的异步现象。

总览

多线程+单对象+synchronized+static（例子）

Service类

public class Service {
    synchronized public static void PrintA() {
        try {
            System.out.println("线程名称为：" + Thread.currentThread().getName() +
                    "在" + System.currentTimeMillis() + "进入printA");
            Thread.sleep(3000);
            System.out.println("线程名称为：" + Thread.currentThread().getName() +
                    "在" + System.currentTimeMillis() + "离开printA");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    synchronized public static void printB() {
        System.out.println("线程名称为：" + Thread.currentThread().getName() +
                "在" + System.currentTimeMillis() + "进入printB");
        System.out.println("线程名称为：" + Thread.currentThread().getName() +
                "在" + System.currentTimeMillis() + "离开printB");
    }

	//注意这个方法不加static
    synchronized public void printC() {
        System.out.println("线程名称为：" + Thread.currentThread().getName() +
                "在" + System.currentTimeMillis() + "进入printC");
        System.out.println("线程名称为：" + Thread.currentThread().getName() +
                "在" + System.currentTimeMillis() + "离开printC");
    }
}

ThreadA.java

public class ThreadA extends Thread {
    private Service service;
    public ThreadA(Service service) {
        this.service = service;
    }
    @Override
    public void run() {
        //注意这里是对象调用
        service.PrintA();
    }
}

ThreadB.java

public class ThreadB extends Thread {
    private Service service;
    public ThreadB(Service service) {
        this.service = service;
    }
    @Override
    public void run() {
        //注意这里是对象调用
        service.printB();
    }
}

ThreadC.java

public class ThreadC extends Thread {
    private Service service;
    public ThreadC(Service service) {
        this.service = service;
    }
    @Override
    public void run() {
        //注意这里是对象调用
        service.printC();
    }
}

Run.java

public class Run {
    public static void main(String[] args) {

        Service service = new Service();
        
        ThreadA a = new ThreadA(service);
        a.setName("A");
        a.start();

        ThreadB b = new ThreadB(service);
        b.setName("B");
        b.start();

        ThreadC c = new ThreadC(service);
        c.setName("C");
        c.start();
    }
}