ByteBuffer: how come the abstract methods work?

Question

I am confused about the abstract methods in ByteBuffer class. Many of the methods in that class are declared abstract but yet I am able to use them without a problem.
For example, put(byte b) is declared abstract in the java docs. But I am able to use that method ( I did not have to extend ByteBuffer and implement this method). I know I must be missing something here...any help would be appreciated.
thanks

Answer 1

Those responses should certainly do the trick. But I love hearing myself type, so here's an example:abstract class Fred
     public abstract void hiThere();
class SubFred extends Fred
     public void hiThere() { println("Greetings Professor Falken"); }
}Somewhere some method says it returns an object of type Fred. To do this they might (as far as you know) create an instance of SubFred and return that to you. SubFred is of type Fred. Your code doesn't know or care (usually) what the ACTUAL class is, as long as it matches what you expect Fred to be from the documentation.