Referring back to a class

Question

when classA creates an instance of classB, how can classB referr back to class A (withough being static) there is the way to use super to do things with the superclass that you extend, but is there a way to access a the class that created an instance of you?
I know that sounds confusing, so ill give an example:
I have a chat client application. It creates an instance of a little class that watches for incomming messages.
Can this watcher class send a little message to the main client reporting that it recieved a message?
or do I have to make a thread and use a method like
public String checkMessage()
to access it, and call this method ever 100 ms or something?
It seems a little bit over done to include a pointer to classA when creating classB:
new classB(this);
public classB(classA Caller)
caller = Caller;
public void recievedMessage(String message)
caller.reportMessage(message);
}just so that class be can report back. can i call a special keyword to find out who created the class instance?

Answer 1

It seems a little bit over done to include a pointer
to classA when creating classB:I wouldn't say it's overdone. If the B is associated with a particular A, and needs to know about that A, then passing a reference to the A into the ctor is the normal way you'd do that. You could also maintain a separate map of which Bs are associated with which As, but I doubt that will benefit you here.
just so that class be can report back. can i call a
special keyword to find out who created the class
instance?Nope.
Objects don't create objects. Code creates objects. The question "Which object created this other object over here?" is best answered "[url http://en.wikipedia.org/wiki/Mu_(Japanese_word)]Mu."