In Eclipse you can open a method definition if you point the method name (its invocation), and hit ctrl + LMB. You can also achieve the same if you select the method call and hit F3, and probably in few other ways.
Try to use this feature on the interface type…
What’s annoying is that when you use this shortcut on a method which uses an interface type rather than the implementing class, you are forwarded to the interface method declaration. Needless to say, this not what you expected (well ok, maybe that’s not what 99.9% of people would expect. ;-)
Solution!
Of course the exact implementor of the interface can be unknown until the runtime, but if you know what implementor will be used or you just want to view some particular implementation, than you can select the method invocation and hit Ctrl + T. This will show you the “Type implementing or defining …” pop-up, where you can choose the Eclipse-known implementation of the method. After you choose it, you will be taken to the particular interface method implementation.