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Java code:

public class TestThreadSynchronized extends Thread{
Time timer = new Time();
public static void main(String[] args){

TestThreadSynchronized t1 = new TestThreadSynchronized();
TestThreadSynchronized t2 = new TestThreadSynchronized();
//t1.setName("t1");
//t2.setName("t2");
t1.start();
t2.start();

}
public void run(){
timer.add(Thread.currentThread().getName());
}
}

class Time{
Time(){}
private static int num = 0;
public synchronized static void add(String s){
num++;
try{
Thread.sleep(1000);
}catch(InterruptedException e){}
System.out.println(s+" ÄãÊÇµÚ "+num+" ¸öʹÓÃÕß");
}
}



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TestThreadSynchronized t1 = new TestThreadSynchronized();
TestThreadSynchronized t2 = new TestThreadSynchronized();
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