Should all methods be static if their class has no member variables

Question

I\'ve just had an argument with someone I work with and it\'s really bugging me. If you have a class which just has methods like calculateRisk or/and calc

Answer 1

I clearly would say no.

It's much harder to change out in the future if you call static methods instead of instance ones. With instance methods it's easy to inject your service, e.g. in Java with an IoC/DI container like Guice or Spring.