多线程-同步代码块

//copyright?liupengcheng //http://www.VEVb.com/liupengcheng

/** * Created by Administrator on 2014/10/24. * synchronized 锁旗标，改变标志位，已达到同一时刻只有一个线程在执行有效操作。 */

public class TheadDemo5 {     public static void main(String[] args)     {         ThreadTest t = new ThreadTest();         Thread t1 = new Thread(t);t1.start();         Thread t2 = new Thread(t);t2.start();         Thread t3 = new Thread(t);t3.start();     } }

class ThreadTest implements Runnable {     PRivate int tickets = 100;     String str = new String("");

    public void run() {         while (true) {             synchronized (str) {                 if (tickets > 0) {                     try {                         Thread.sleep(10);                     } catch (Exception e) {                         System.out.println(e.getMessage());                     }                     System.out.println(Thread.currentThread().getName() + "is saling ticket" + tickets--);                 }             }         }     } }

/** * 结果为 * Thread-0is saling ticket100 Thread-0is saling ticket99 Thread-0is saling ticket98 Thread-0is saling ticket97 Thread-0is saling ticket96 Thread-0is saling ticket95 Thread-2is saling ticket94 Thread-2is saling ticket93 Thread-2is saling ticket92 Thread-2is saling ticket91 Thread-2is saling ticket90 Thread-2is saling ticket89 Thread-2is saling ticket88 Thread-2is saling ticket87 Thread-2is saling ticket86 Thread-2is saling ticket85 Thread-2is saling ticket84 Thread-2is saling ticket83 Thread-2is saling ticket82 Thread-2is saling ticket81 Thread-2is saling ticket80 Thread-2is saling ticket79 Thread-2is saling ticket78 Thread-2is saling ticket77 Thread-2is saling ticket76 Thread-2is saling ticket75 Thread-2is saling ticket74 Thread-2is saling ticket73 Thread-2is saling ticket72 Thread-2is saling ticket71 Thread-2is saling ticket70 Thread-2is saling ticket69 Thread-2is saling ticket68 Thread-2is saling ticket67 Thread-2is saling ticket66 Thread-2is saling ticket65 Thread-2is saling ticket64 Thread-2is saling ticket63 Thread-2is saling ticket62 Thread-2is saling ticket61 Thread-2is saling ticket60 Thread-2is saling ticket59 Thread-2is saling ticket58 Thread-2is saling ticket57 Thread-2is saling ticket56 Thread-2is saling ticket55 Thread-2is saling ticket54 Thread-2is saling ticket53 Thread-2is saling ticket52 Thread-2is saling ticket51 Thread-2is saling ticket50 Thread-2is saling ticket49 Thread-2is saling ticket48 Thread-2is saling ticket47 Thread-2is saling ticket46 Thread-2is saling ticket45 Thread-2is saling ticket44 Thread-2is saling ticket43 Thread-2is saling ticket42 Thread-2is saling ticket41 Thread-2is saling ticket40 Thread-2is saling ticket39 Thread-2is saling ticket38 Thread-2is saling ticket37 Thread-2is saling ticket36 Thread-2is saling ticket35 Thread-2is saling ticket34 Thread-2is saling ticket33 Thread-2is saling ticket32 Thread-2is saling ticket31 Thread-2is saling ticket30 Thread-2is saling ticket29 Thread-2is saling ticket28 Thread-2is saling ticket27 Thread-2is saling ticket26 Thread-2is saling ticket25 Thread-2is saling ticket24 Thread-2is saling ticket23 Thread-2is saling ticket22 Thread-2is saling ticket21 Thread-2is saling ticket20 Thread-2is saling ticket19 Thread-2is saling ticket18 Thread-2is saling ticket17 Thread-2is saling ticket16 Thread-2is saling ticket15 Thread-2is saling ticket14 Thread-2is saling ticket13 Thread-2is saling ticket12 Thread-2is saling ticket11 Thread-2is saling ticket10 Thread-2is saling ticket9 Thread-2is saling ticket8 Thread-2is saling ticket7 Thread-2is saling ticket6 Thread-2is saling ticket5 Thread-2is saling ticket4 Thread-2is saling ticket3 Thread-2is saling ticket2 Thread-2is saling ticket1

*/