同步里面的this

synchronized(this)用法

public class test {
 
 private Thread startingNextJob = null;
 
    protected final void startNextJob() {
        synchronized (this) {
         System.out.println(this.getClass().getName());
            if(startingNextJob != null) {
                try {
                    startingNextJob.join();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                    return;
                }
            }
            startingNextJob = new Thread(new Runnable() {
                public void run() {
                    //startNextJobInternal();
                 System.out.println("我在这里");
                }
            }, "StartNextJob");
            startingNextJob.start();
        }
    }
    public void init(){
     startNextJob();
    }
}
public class test2 extends test{
 public void te(){
  init();
 }
 public static void main(String args[]){
  test2 tt = new test2();
  tt.te();
 }
}

 用test2类来继承test，调用init()办法，测试synchronized(this)是哪个对象。结果是test2对象。