//包含了synchronized 方法的类
public class SynchronizedMethod {public synchronized void test(){System.out.println("线程开始..");try {Thread.sleep(2000);} catch (Exception e) {e.printStackTrace();}System.out.println("线程结束..");}
}//测试类
public class MyThread extends Thread{public void run(){SynchronizedMethod clazz = new SynchronizedMethod();clazz.test();}public static void main(String[] args) {for(int i=0;i<3;i++){Thread thread = new MyThread();thread.start();}}}

执行结果:

线程开始..
线程开始..
线程开始..
线程结束..
线程结束..
线程结束..

 1 //修改测试类代码如下，使用同一对象调用test方法
 2
 3 public class MyThread extends Thread{
 4
 5     /**
 6      * Author:LearnAndGet
 7      */
 8     private SynchronizedMethod sync;
 9     public MyThread(SynchronizedMethod sync)
10     {
11         this.sync = sync;
12     }
13
14     public void run(){
15         sync.test();
16     }
17
18
19     public static void main(String[] args) {
20         SynchronizedMethod sync = new SynchronizedMethod();
21         for(int i=0;i<3;i++)
22         {
23             MyThread thread = new MyThread(sync);
24             thread.start();
25         }
26     }
27 }

　运行结果：

线程开始..
线程结束..
线程开始..
线程结束..
线程开始..
线程结束..

public class SynchronizedMethod {public void test(){//将代码块使用synchronized锁住synchronized(SynchronizedMethod.class){System.out.println("线程开始..");try {Thread.sleep(2000);} catch (Exception e) {e.printStackTrace();}System.out.println("线程结束..");}}
}