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Question about the FrontController

Timothy Sam
Ranch Hand

Joined: Sep 18, 2005
Posts: 751
Hi guys, I'm still thinking if I understood the front controller correctly. I have a class that processes a response attribute named "page". Then, depending on its value I have multiple if statements and depending on the condition met, forwards to a specific page. Is this an example of the front controller? Or is this just another bad practice I'm doing? I have read Bear's article about this but unfortunately I just don't get it...

SCJP 1.5
Bear Bibeault
Author and ninkuma

Joined: Jan 10, 2002
Posts: 63858

Originally posted by Timothy Sam:
I have a class that processes a response attribute named "page".

Please clarify regarding "response attribute"? There's no such animal. Can I assume that you mean request parameter?

What are you are doing is indeed implementing a front controller (if I understand you correctly), but using nested if's is a poor way to do it. That means that every time you add a new Command to the app, you need to add and if block for it.

Rather, a typical front controller will use a configuration of some type to map the "command verb" to a class that it dynamically instantiates. That way, nothing need be hard-coded into the front controller itself, and commands can be added to the system without adding any code (except for the command class itself, of course).

I do need to apologize a bit... it was originally my intention to follow up on the article you mentioned with one on the design of just such a front controller which I have written. But other writing tasks have taken precedence and I haven't been able to get to it. I hope to have it available for the next Journal though...

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Timothy Sam
Ranch Hand

Joined: Sep 18, 2005
Posts: 751
Thank you Bear. The animal I'm referring to is indeed a request parameter and not a response attribute. I understood everything fully, thanks a lot.
I agree. Here's the link:
subject: Question about the FrontController
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