Comments on: The Strategy Pattern

By: Zephyr

Zephyr — Wed, 19 Oct 2011 16:20:59 +0000

To add to my previous comment: Is there a way to determine the strategy without requiring a switch? Would it be possible to say: “This value was passed in, now who wants to deal with it?”

By: Zephyr

Zephyr — Wed, 19 Oct 2011 16:18:33 +0000

Thank you for this article. It helped me rethink a big switch statement I have. However, it still appears you would need a switch statement to handle the choice of strategy. Correct me if I am wrong (please do, because I would like a better way), but in the situation you mentioned, you would need to change the strategy depending on salary and this would require a switch or check of some sort.

By: Anonymous

Anonymous — Sat, 01 May 2010 07:26:34 +0000

Amazing post, you’ve helped me understand the strategy!

By: Geoff Denning

Geoff Denning — Sat, 29 Aug 2009 18:47:01 +0000

Thanks for this great example of the Strategy pattern, this helped me to understand this pattern much better than any other reference I’ve found online so far.

I just wanted to point out a few minor mistakes in the code, which had me a bit confused at first:

* In the AmountObject abstract class, setAmountStrategy should return void.
* The AmountBehavior interface should be named AmountStrategy.
* The AmountStrategyImpl class should extend AmountObject (not AmountStrategy).
* The AmountStrategyExample class should not extend anything.
* In the AmountStrategyExample class, the amountStrategy.getAmount(); line should actually say amountStrategy.calculateAmount();

By: Giorgio Sironi

Giorgio Sironi — Mon, 11 May 2009 19:09:43 +0000

I reached this post from a link on a new one, but it seems that there is some problems with naming. The AmountStrategy class is not implemented anywhere (maybe it has been renamed in AmountBehaviour).

By: Carsten

Carsten — Mon, 11 May 2009 12:39:23 +0000

This is exactly what I stumbled upon a few days ago. Err, what I whish I had found. But really I found a couple of if and switch statements that crumple up lots of functionality into a single method…