- package demo1;
- class Ticket implements Runnable
- {
- private int tick = 100;
- Object obj = new Object();
- boolean flag = true;
- public void run()
- {
- if(flag)
- {
- while(true)
- {
- this.flag = false;
- synchronized([color=Red]obj[/color])
- {
- if(tick > 0)
- {
- try{
- Thread.sleep(100);
- }catch(Exception e)
- {
- }
- System.out.println(Thread.currentThread().getName() + " code.... " + tick-- );
-
- }
- }
- }
- }
- else
- while(true)
- show();
- }
- public [color=Red]synchronized[/color] void show()
- {
- if(tick>0)
- {
-
- try{
- Thread.sleep(100);
- }catch(Exception e)
- {
- }
- System.out.println(Thread.currentThread().getName() + " show.... " + tick-- );
-
- }
- }
- }
- class TicketDemo2
- {
- public static void main(String[] args)
- {
- Ticket t = new Ticket();
-
- Thread t1 = new Thread(t); //创建一个线程
- Thread t2 = new Thread(t); //创建一个线程
- t1.start();
- t2.start();
- }
- }
复制代码 用的不是同一个锁,方法同步用的this,而同步代码块用的却是obj,所以打出了0 |