Is there any tool/software that decouples Java Swing GUI logic and business logic?

Question

I have been working on Java Swing project. Its design is pretty poor. I have been given task to make its design better. Primarily I was thinking that I will decouple Java Swing code and the business code by following MVC pattern.

Doing this stuff manually seems error prone. Is there any tool/software that decouples GUI layer code (written in Java Swing) and the business layer code (written in core Java).

Answer 1

As far as I can tell the answer to that question is "No, there is not such a tool."

I would hazard a guess to say that it is not even likely that someone could make such a tool. The problem is that thereis no easy way to distinquish between "business logic" and "GUI" code.

On projects that I have worked on, we made a concerted effort in the design phase to keep the GUI and the business logic separate, but I can't count the number of times that it was unavoidable that there was cross-over, especially when some business rule drove how the GUI should behave.

I don't envy your task. Dealing with, and modifying existing code, especially code that you didn't create, IS error prone. And the whole concept of MVC programming is really just way to think about how you build a program not a set of existing library of tools to use.

I learned MVC programming back in Smalltalk days, when it was originally invented by the smart people at Xerox Parc, and even they couldn't avoid some cross-over coupling of code.

Answer 2

Automated tools work well when the input is well defined and structured. Based on what you have described, your inputs are far from that.

Yes, doing this work is going to be complicated and a lot of work. But this is something that you just need to roll up your sleeves and dive into it. Before you start touching the code, sit down and make sure you fully understand how things are laid out now (and why that is a bad thing). Then start planning how you would do it better.

Now that you have a plan of how things should be, start working with the code and updating the legacy code.

Answer 3

There isn't a tool, but there are techniques.

Refactoring is a practice of making small changes to code to alter it's architecture without altering it's function. You've already probably done refactoring to a degree, but sometimes reading up on a subject you know about can help sharpen one's skills.

Many IDEs do support some of the simple refactorings. Eclipse and NetBeans have different strengths in their refactoring support, and depending on your current environment, you may find one to be more useful than the other.

What refactoring won't do for you is to give you a roadmap of how to get from point A (your spaghetti code) to point B (your cleanly separated out MVC). Instead it will just make you a better driver along the path. Unfortunately, (or fortunately for all the developers out there) good brains are still needed to figure out what sections of code intend to do, and whether they are more appropriately placed in the Model, View, or Controller. The rest is just teasing out the dependencies in such a manner that you can eventually move the code up or down in the sequence, and eventually push it into a method that can then be moved to the appropriate class.

Good luck.

Answer 4

I also don't know of any tool. And as others here - kind of - point out, I think such tools would end up making programmers redundant. We don't want that, do we. :-D

But, checking manually if you actually managed to decouple the code should not be to complicated. Just make sure your "business part" imports no swing packages:

• find in files "swing"
• move all those files in one package
• check if there is any "business logic" in there => take it out
• ...