Comments on: Head First Design Pattern Question

By: Anonymous

Anonymous — Mon, 20 Jun 2005 11:43:16 +0000

You could use a decorator pattern to encapsulate the pizza toppings if you wanted to.

The point of the factory is that the assembling of the class is encapsulated by the factory, so you could swap one factory for another.

By: darrell

darrell — Tue, 24 May 2005 07:45:53 +0000

I think Thomas is right about the “last-resort” thing. Decorator ends up having tons of wrappers, and in their example you’d have to do a lot of work to re-order the coffee decorators to say “double-mocha” whereas if you had developed it differently, double-mocha is easy.

By: GooberDLX

GooberDLX — Tue, 24 May 2005 06:41:35 +0000

first: i love the book, great way to introduce patterns to a developer…

second: i think it was merely an example of the factory pattern. straight up. just as in actual development, there are also a million ways to describe the same thing.

By: breichelt

breichelt — Tue, 24 May 2005 05:40:22 +0000

Interesting, I have to go back and look at that chapter again, its been awhile since I read that one, I’ll report back

By: Anonymous

Anonymous — Tue, 24 May 2005 03:44:20 +0000

Isn’t Decorator some kind of a last resort? Something you use when you need to change what’s already there, but you can’t do the way you want?

In this context, Decorator makes sense in the coffe shop, because they are expanding an existing architecture. If the pizza shop is starting from scratch, then you don’t have that limitation.

I am guessing on the pizza shop, as I haven’t bought the book yet, only read the sample chapter.