java 多线程-Runnable接口

new Thread(Run).start()

public void run()
{
for(int i=0;i<5;i++)
{
    System.out.println("aa");
}
}

public static void main(String[]args)
{
ThreadDownload ra=new ThreadDownload();
Thread it=new Thread(ra);
it.start();

//或者
new Thread(new ThreadDownload()).start();

for(int i=0;i<5;i++)
{
    System.out.println("ff");
}
}