Anonymous class - reference to enclosing object

Question

Hi,
I have a class (which is in fact an Adapter that implements several interfaces
for EventListener) that should be instantiated in the code via an anonymous
class, i.e. like this
this.addAdapter( new Adapter() {
// implemented methods here
Now I have the problem that when I pass the instance of the anonymous class
later to a method somewhere else, I need a reference to the object which
instantiated it:
public class AClass {
priavte BClass bClass;
private Adapter adapter;
public AClass() {
this.addAdapter( new Adapter() {
// implemented methods here
bClass = new BcLass();
bClass.doSomething
void addAdpater( Adpater ad ) {
this.adpater = ad;
public class BClass {
public BClass() {
doSomething( Adapter ad ) {
// how can I get a reference to the instance
// of AClass that called this method ?????
My IDE shows the needed object as member this$0 of the Adpater, so I
suppose there is some way to get at the reference to this enclosing
object, but how???
Thanks in advance for any idea,
Leif

Answer 1

If it's possible to get the reference without the adapter explicitly giving it to you, then everything that's been written about read-only adapters is silly, so I would bet that it's not possible.
Your adapter is written as an inner class, so it has access to all the enclosing object's state. If you can modify the adapter class, you could expose as much of that state as you wanted. Maybe that's as good as the reference for your purposes.
But maybe not. So the only option I could see is that the adapter itself has a method
public AClass getEnclosingAClassInstance()
which returns a reference to the enclosing class. The way to set it might be to make a corresponding set method which AClass calls with 'this' before handing off the adapter to BClass, or by AClass itself providing a getThis method, which the adapter could call. I'm pretty sure you can't get anymore direct access to the enclosing 'this', because the adapter's 'this' shadows it.
All of which leaves me wondering--why? It's so weird and un-adapter-like that I suspect it's the wrong idiom. But maybe you know something I don't....