public void run()  
    {  
  
        while(true)  
        {  
            synchronized(obj)  
            {  
                if(tick > 0)  
                {  
                    //try{Thread.sleep(40);}catch(Exception e){}  
                    System.out.println( Thread.currentThread().getName() + " sail --" + tick--);  
                }     
            }  
        }  
    }