Java 多线程 （PART XI）synchronized（IV）关于synchronized（非this对象X）

格式：

public Object myobject=new Object();
public void Method(){

synchronized (myobject){
/**
block body
*/
}
}

作用：

实例代码：

package hello;
class MyObject{

}
class Service{
private String usernameParam;
private String passwordParam;
private MyObject myObject=new MyObject();

public void setUsernamePassword(String username,String password) {
try {
synchronized(myObject) {
System.out.println("线程名称为："+Thread.currentThread().getName()+"在"+System.currentTimeMillis()+"进入同步块");
this.usernameParam=username;
Thread.sleep(3000);
this.passwordParam=password;
System.out.println("线程名称为："+Thread.currentThread().getName()+"在"+System.currentTimeMillis()+"离开同步块");

}

} catch (InterruptedException e) {
e.printStackTrace();
}

}
}
class ThreadA extends Thread{

private Service service;
public ThreadA(Service service) {
this.service=service;
}
@Override
public void run() {
this.service.setUsernamePassword("a", "aa");
}
}
class ThreadB extends Thread{

private Service service;
public ThreadB(Service service) {
this.service=service;
}
@Override
public void run() {
this.service.setUsernamePassword("b", "bb");
}
}
public class Main {

public static void main(String[] args) {
Service service=new Service();
ThreadA threada=new ThreadA(service);
threada.setName("A");
threada.start();
ThreadB threadb=new ThreadB(service);
threadb.setName("B");
threadb.start();
}

}

运行结果：

线程名称为：A在1507454349271进入同步块
线程名称为：A在1507454352272离开同步块
线程名称为：B在1507454352273进入同步块
线程名称为：B在1507454355273离开同步块