consider this example
Thread t=new Thread(){
public void run()
{
System.out.println("run");
}
};
t.start();
here a subclass of Thread is created and assigned to the Thread super class
what i mean to say is that by default if u create an anonymous class it is a subclass of declared class
and according to k&b u cannot extend and implement at the same time
but here u can implement an interface and by default ur extending Thread class
hope that helps