当synchronized关键字和this关键字

package cn.itcast_01_mythread.thread.testThread;

public class MyThreadWithImpliment_Synch_method implements Runnable {

    int x;

    public MyThreadWithImpliment_Synch_method(int x) {

        this.x = x;

    }

    public synchronized void queryCurrentTime(){

        for (int i = 0; i < 10; i++) {

            String name = Thread.currentThread().getName();

            System.out.println("to "+name + " current is " + i);

            /*try {

                //Thread.sleep(100);

            } catch (InterruptedException e) {

                // TODO Auto-generated catch block

                e.printStackTrace();

            }*/

        }

    }

    @Override

    public void run() {

        String name = Thread.currentThread().getName();

        System.out.println("线程" + name + "的run方法被调用……");

        this.queryCurrentTime();

//queryCurrentTime();

    }

    public static void main(String[] args) {

        Thread thread1 = new Thread(new MyThreadWithImpliment_Synch_method(1), "thread-1");

        Thread thread2 = new Thread(new MyThreadWithImpliment_Synch_method(2), "thread-2");

         thread1.start();

         thread2.start();

        // 注意调用run和调用start的区别,直接调用run，则都运行在main线程中

//        thread1.run();

//        thread2.run();

    }

}

this.queryCurrentTime();//执行的结果，结果与预期的一样

线程thread-2的run方法被调用……

to thread-2 current is 0

to thread-2 current is 1

to thread-2 current is 2

to thread-2 current is 3

to thread-2 current is 4

to thread-2 current is 5

to thread-2 current is 6

to thread-2 current is 7

to thread-2 current is 8

to thread-2 current is 9

线程thread-1的run方法被调用……

to thread-1 current is 0

to thread-1 current is 1

to thread-1 current is 2

to thread-1 current is 3

to thread-1 current is 4

to thread-1 current is 5

to thread-1 current is 6

to thread-1 current is 7

to thread-1 current is 8

to thread-1 current is 9

queryCurrentTime();//执行的结果与预期的不一样！！，好像就没有实现锁的功能

线程thread-1的run方法被调用……

线程thread-2的run方法被调用……

to thread-1 current is 0

to thread-2 current is 0

to thread-1 current is 1

to thread-2 current is 1

to thread-1 current is 2

to thread-2 current is 2

to thread-1 current is 3

to thread-2 current is 3

to thread-1 current is 4

to thread-2 current is 4

to thread-1 current is 5

to thread-2 current is 5

to thread-1 current is 6

to thread-2 current is 6

to thread-1 current is 7

to thread-2 current is 7

to thread-1 current is 8

to thread-2 current is 8

to thread-1 current is 9

to thread-2 current is 9

看疯狂java上说的，对于synchronized修饰的实例方法（非static方法）而言，无须显示指定同步监视器，同步方法监视器是this也就是调用该方法的对象。

所以我的理解是对于synchronized是站在对象的级别的，不是站在方法的级别的，如果直接在同一个类不通过this关键字调这个方法那么同步锁就没有加上同时代码不会报任何错误

synchronized和lock都是多线程的时候调用的，如果在javaweb中使用这些，而线程是有容器（tomcat）产生的不是我们自己产生的，这中做法很难测试，比如单例模式

比较好的做法是在我们自己写代码的时候结合业务需要建立多线程，然后用synchronized或lock

ps：用的是jdk1.8

巴特西

当synchronized关键字和this关键字

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