【笔记】synchronized共享代码块

package sync;

public class Ticket implements Runnable {
    private int ticket = 100;
    private Object lock = new Object();


    @Override
    public void run() {

        while (true) {
//            synchronized (任意对象)：对象是唯一的
            synchronized (lock){
                if (ticket <= 0) {
                    break;
                } else {
//                    try {
//                        Thread.sleep(1000);
//                    } catch (InterruptedException e) {
//
//                    }
                    ticket--;
                    System.out.println(Thread.currentThread().getName() + "在买票，还剩" + ticket + "票");
                }
            }

        }
    }
}

package sync;

public class SyncDemo {
    public static void main(String[] args) {
        Ticket ti = new Ticket();

        Thread tr1 = new Thread(ti);
        Thread tr2 = new Thread(ti);
        Thread tr3 = new Thread(ti);

        tr1.setName("老王");
        tr2.setName("老李");
        tr3.setName("老张");

        tr1.start();
        tr2.start();
        tr3.start();
    }
}