mutithreding in java :create thread using Runnable

class RunnableThread implements Runnable{

 Thread runner;
 public RunnableThread() {
 }

 public RunnableThread(String threadName) {
        runner = new Thread(this, threadName);   // (1) Create a new thread.
        System.out.println(runner.getName());
        runner.start();                          // (2) Start the thread.
 }

 public void run(){
  //Display info about this particular thread
  System.out.println(Thread.currentThread());
 }


}
public class RunnableExample{
 
 public static void main(String[] args){
     Thread thread1 =  new Thread(new RunnableThread(),"thread1");
     Thread thread2 =  new Thread(new RunnableThread(),"thread2");
     RunnableThread thread3 = new RunnableThread("thread3");

//Start the threads
     thread1.start();
     thread2.start();
     try{
       //delay for one second
       Thread.currentThread().sleep(1000);
     }catch(InterruptedException e){}

     //Display info about the main thread   
     System.out.println(Thread.currentThread());       
 }
}