线程模拟下载

class LoadDown implements Runnable{
     static double num=0;
      static double n1 =0;
      static double n2 =0;
      static double n3 =0;
      static double n4 =0;
    public void run(){
        
        while(true){
            synchronized ("锁") {
            if (num<=500) {
                try {
                    Thread.sleep(10);
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                if(Thread.currentThread().getName().equals("下载线程一")){
                    n1 +=1;
                }else if (Thread.currentThread().getName().equals("下载线程二")) {
                    n2 +=1;    
                }else if(Thread.currentThread().getName().equals("下载线程三")) {
                    n3 +=1;
                }else if(Thread.currentThread().getName().equals("下载线程四")) {
                    n4 +=1;
                }
                System.out.println(Thread.currentThread().getName()+"已下载"+(num/500)*100+"%");
                num++;
            }else{
                System.out.println("已经下载完成");
                break;
            }
            }
            
        }
         System.out.println("每个线程各下载: "+(n1/500)*100+"%"+"\t\t"+(n2/500)*100+"%"+"\t"+(n3/500)*100+"%"+"\t"+(n4/500)*100+"%"+"\t");
         System.out.println(n1+" "+n2+" "+n3+" "+n4);
    }
    
    
}


public class demo1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        LoadDown loadDown =new LoadDown();
        Thread thread1=new Thread(loadDown,"下载线程一");
        Thread thread2=new Thread(loadDown,"下载线程二");
        Thread thread3=new Thread(loadDown,"下载线程三");
        Thread thread4=new Thread(loadDown,"下载线程四");
        
        thread1.start();
        thread2.start();
        thread3.start();
        thread4.start();
        
        
    }

}