Java concurrent programming-synchronization and asynchrony of object locks

package cn.bufanli.test;

/**
 * 同步: synchronized
 *      同步的概念是共享;
 * 异步: asynchronized
 *      异步的概念是独立,相互之间没有任何制约.和http发ajax请求,页面还可以做其他操作,二者没有任何关系
 *      同步的目的就是为了线程安全,对于线程来说,需要满足两个特性: 原子性 (同步) 可见性
 */
public class MultiThread1 {
    public synchronized void method1() {
        try {
            System.out.println(Thread.currentThread().getName());
            Thread.sleep(4000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    public  void method2()  {
        System.out.println(Thread.currentThread().getName());
    }

    /**
     * 总结:
     *      A线程持有Object对象的Lock锁,B线程如果要调用synchronized修饰的方法就要等待,这就是同步
     *      A线程持有Object对象的Lock锁,B线程可以以异步的方式调用对象中非synchronized修饰的方法,这就是异步
     * @param args
     */
    public static void main(String[] args) {
       final MultiThread1 multiThread1 = new MultiThread1();
        Thread thread = new Thread(() -> {
            multiThread1.method1();
        },"method1");
        thread.start();
        Thread thread2 = new Thread(() -> {
            multiThread1.method2();
        },"method2");
        thread2.start();

    }
}

 

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Origin blog.csdn.net/adminBfl/article/details/102895628