线程--实现Runnable接口

Class SynDemo implemets Runable
{
    private int i;
    SynDemo(int i){
         this.i = i;
    }
    public void run(){
        while(true){
            if(i > 0){
                   System.out.printlnt(Thread.currentThread().getName()+"==="+i--);
            }
        }
    }
}  

Class TestDemo
{
    public static void main(String[] args){
             SynDemo syn = new SynDemo();//SynDemo 对象不是个线程，所以需要跟Thread类产生关系需要创建一个Thread类，所以需要告诉Thread线程需要运行的代码
            Thread t1 = new Thread(syn);
            Thread t2 = new Thread(syn);
            Thread t3 = new Thread(syn);
            Thread t4 = new Thread(syn); 
 
            t1.start();
            t2.start();
            t3.start();
            t4.start();


    }
}