swing实现双击Shift

Java swing 如何实现双击Shift呢?

Java代码  

1. startTimeField_3.addKeyListener(new KeyListener() {  
2.             private long lastTimeMillSencond;  
3.             @Override  
4.             public void keyTyped(KeyEvent e) {  
5.             }  
6.               
7.             @Override  
8.             public void keyReleased(KeyEvent e) {  
9.             }  
10.               
11.             @Override  
12.             public void keyPressed(KeyEvent e) {  
13.                 if(e.isShiftDown()){  
14.                     if(lastTimeMillSencond==0){  
15.                         lastTimeMillSencond=System.currentTimeMillis();  
16.                     }else{  
17.                         long currentTime=System.currentTimeMillis();  
18.                         if(currentTime-lastTimeMillSencond<1000){  
19.                             System.out.println("双击Shift");  
20.                             lastTimeMillSencond=0;  
21.                         }else{  
22.                             lastTimeMillSencond=System.currentTimeMillis();  
23.                         }  
24.                     }  
25.                 }  
26.             }  
27.         });  

 下面的是错误的:

 

会导致:连续按下Shift 3次,会造成两次双击Shift