Andrew asks this about aspect-oreinted programming (AOP) in my comments: "my main problem when thinking about that sheeat is 'how do you write the GUI?'"

The simple answer is: you don't write GUIs in AOP. AOP is meant to be used in conjunction with regular Java. So you write your Java code and then write aspects that "cross-cut" that Java code. All cross-cutting means is that you are writing code in one place (an aspect) that ends up doing work automatically in many other methods. The logging example given in Improve Modularity with Aspect-Orietented Programming is pretty good.

A software architect no longer has to enforce a logging coding policy in some coding standards book and then do audits to see that it is followed correctly. He can write the logging aspect and it will work in all methods that need it, whereas before these logging methods might have been in an area of the project known as "common".

So the GUI is written the same as before. AOP cannot exist without regular Java code as far as I can understand it.