How to use the Runnable??

[Yashnoo lyo]

Why I must create a Thread object when I use the run method? Despite I use the Runnable implements?
my code is:
public class testRun implements Runnable{
String id;
Thread thread=new Thread();
public testRun(String str){
id=str;
}
public void run(){
for(int i=0;i<1000;i++){
for(int j=1;j<100;j++);
try{
thread.sleep((int)(1000*Math.random()));
}catch(InterruptedException e){}
System.out.println(id+"is running");
}
}
}
class testC{
public static void main(String args[]){
testRun dog=new testRun("hello");
testRun cat=new testRun("JavaBean");
Thread t1=new Thread(dog);
Thread t2=new Thread(cat);
t1.start();
t2.start();
}
}
////////////////////////////////////////////
when I delete the :
Thread t1=new Thread(dog);
Thread t2=new Thread(cat);
use dog.start();
cat.start();
It can't run! saying:can't solve the dog?Why I must create a Thread Object? Thank you!

[William Brogden]

This is very basic Java. You should study the free Java tutorial available at java.sun.com or any of the other free resources. This forum exists for JavaServer Pages questions.
Bill