Make IndicesClient non-final, but make its methods final.

[hariso]

This should make writing unit tests an easier task. It's basically the same as #27238.

Comment here is the motivation.

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[elasticmachine]

Since this is a community submitted pull request, a Jenkins build has not been kicked off automatically. Can an Elastic organization member please verify the contents of this patch and then kick off a build manually?

[hariso]

@elasticmachine Why are you spamming? :D

[javanna]

hi @hariso I am not a big fan of this change as the reason is only testing. #27238 had different reasons, like the need to add support for custom endpoints. I am not sure this is needed in IndicesClient but I see the testing problems that are caused by not being able to mock the class so I am considering getting it in. I see that despite the class is non-final though, still there is no way to use a custom subclass in RestHighLevelClient due to the way IndicesClient is created. Is this good enough to make your tests happy?

[hariso]

@javanna Thanks for feedback and new info which I just learnt! Actually, this is not enough to make the tests happy. The configuration I used for my tests was a bit hacky, so a non-final class with final method still doesn't work. I'll close this PR since it doesn't really solve the problem, and try finding another solution.

Thanks again!