package helloworld;

class PrintNum implements Runnable{
    int num;
    Thread mythread;
    Object obj;
    
    public PrintNum(int _num,Object _obj){
        num=_num;
        obj=_obj;
        mythread=new Thread(this);
        mythread.start();
    }
    
    public void run(){
        synchronized(obj){
            while(true){
                while(helloworld.nowstate!=num){
                    try{
                        obj.wait();
                    }catch(InterruptedException ie){
                        System.out.println(ie);
                    }
                }
                helloworld.nowstate=(helloworld.nowstate+1)%10;
                System.out.println(num);
                obj.notifyAll();
            }
        }
    }
}

public class helloworld{
    static int nowstate=0;
    public static void main(String []args){
        Object lock=new Object();
        PrintNum obj[]=new PrintNum[10];
        for(int i=0;i<10;i++)
            obj[i]=new PrintNum(i,lock);
    }
}
 

使用Java實現多個線程輪流顯示數字