Question

Currently doing a group project for college in Java. The assignment is to produce a zero-conf based distributed system. Our group decided on a conference chat application, using client-server architecture. As I joined the group late, a bulk of the code was already completed, and they had decided to develop an MVC architecture for the project. I have experience myself with MVC through Rails development, and can appreciate how handy it is in that context. However, I can’t see the benefits of using it the way it has been implemented by my group.

There are two classes for Client and Server, each of which contains methods for sending and receiving datagrams, and fields such as sockets to enable the sending. There are also ServerController and ClientController classes. Each of these classes consists of only one field(a Server and a Client respectively), and all the methods are either wrappers for the public methods of the Server or Client, or simple utility methods. An example would be:

public void closeDownServer(){
    server.closeDownServer();
}

To me, this seems completely pointless, and that in this instance MVC has been implemented just for the sake of using a design pattern. Can anyone tell me if there is any benefit to coding the application in this way? Is there any need for these controller classes at all?

Answer 1

The purpose of MVC is to provide abstraction to make later changes easier to implement, and to decouple your components. That might be why you see it as pointless now…. because your application is small and simple. If it will stay that way, then MVC might just be added bloat to your application. But if it’s going to grow, MVC might be helpful for future development.

Consider a few cases that might illustrate why you would want to use MVC or an implementation that let model and view access each other directly, without a controller.

• What if you need to perform some other actions when “closing the
  server” that aren’t related to your server class specifically? Where
  would you do this?
• What if you wanted to change your server implementation to a third party package? Would you rather change your controller code or change
  implementation specific code in all your views?
• What if you change the database you are using to store application data? Do you want your UI developers worrying about changing code in
  the front end to accommodate this?

All of the above situations can be mitigated by using MVC, which will give you the proper separation of concerns and abstraction necessary to make developing and improving/changing code easier.