//利用两个线程实现1到100的计算
     public class MyRannable implements  java.lang.Runnable{
         private Thread th_0;
         private Thread th_2;
         int sum=0;//存储累加和的结果
         int i=1;
         public void run(){
             String thName=Thread.currentThread().getName();//获取当前线程的名字
             while (i<=101){
                 System.out.println( "当前线程"+thName+"正在计算" );
                 System.out.println( "当前的累加和" +sum);
                 sum+=i++;
                 if(i==50&&thName.equals( "线程1" )){
                     break;
                 }
                 try {
                     Thread.sleep( 100 );
                 }catch (InterruptedException e){
                     e.printStackTrace();
                 }
             }
         }
         public MyRannable(Thread t0,Thread t2){
             if(t0==null){
                 th_0=new Thread( this );//th0和th2共享一个实现runnable的实例
             }
             if(t2==null){
                 th_2=new Thread( this );
             }
             th_0.setName( "线程1" );
             th_2.setName( "线程2" );
             th_0.start();//启动线程t0
             try {
                 th_0.join();
             }catch (InterruptedException e){
                 e.printStackTrace();
             }
             th_2.start();
         }
     }测试类
    public class test106 {
         public static void main(String[] args){
             //Thread t0=new Thread(  );
             //t0.setName( "线程1" );
             //Thread t2=new Thread(  );
             //t2.setName( "线程2" );
             Thread t0=null;
             Thread t2=null;
             MyRannable ran=new MyRannable( t0,t2 );
         }
     }