Template design pattern - how to "share" implementations?

Question

Working on a project so I'll try to generalize this.

Say I have an abstract class A with an abstract method method().

There are 4 subclasses of A: B, C, D, and E, but B and C have the same exact implementation of method(), and D and E have the same exact implementation of method(). How can I organize the code in such a way that minimizes duplicate code?

Do you really need to use a template method? You can have two subclasses of A - one for each method. Then you can have B and C extend one, and D and E extend the other one. If you don't want more subclasses and can ditch the template method, you can go with a strategy pattern: a strategy for each method and then compose the classes with the corresponding strategy. — Ricardo Costeira, Apr 21 '19 at 00:43

score 0 · Answer 1 · answered Apr 21 '19 at 01:40

0

put the common method in A or in a subclass of a. override the method in the cases where it is different.

answered Apr 21 '19 at 01:40

Ray Tayek

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if I put the method in A, what if there are multiple subclasses that have the same implementation, but are different than A's? – Hello Apr 21 '19 at 01:50
you can put them in Asub1 and Asub2 then subclass the one you want – Ray Tayek Apr 21 '19 at 02:05
should Asub1 and Asub2 be abstract too? (A is abstract) – Hello Apr 21 '19 at 19:26
either way. if the implementation of one of these is complete, the make it non abstract. – Ray Tayek Apr 22 '19 at 02:11

Template design pattern - how to "share" implementations?

1 Answers1