Delete unused methods in DefaultCodegen

[ackintosh]

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Description of the PR

(details of the change, additional tests that have been done, reference to the issue for tracking, etc)

[jmini]

Thank you for this PR, it makes me aware of dead code.

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Before removing those method, did we make an analysis about where they were used in swagger-generator v2?

For example #197 is about oneOf, maybe the method isDiscriminatorInInterfaceTree(..) could be useful (this is just a guess, I did not do an analysis yet).

[ackintosh]

Sounds like a good idea.

But I think that it is better to delete the codes that is not currently in use as it is difficult to predict whether or not to use that codes. (My point is making the codes in this project more simply and keep.)

Even if we need the deleted code, it is easy to copy and use it.

What do you think?

[jmini]

But I think that it is better to delete the codes that is not currently in use as it is difficult to predict whether or not to use that codes. (My point is making the codes in this project more simply and keep.)

dead/unused/commented code is not a good thing... I totally agree with you.

[wing328]

@ackintosh thanks for the PR to clean up unused methods.

@jmini very good point about the need to understand how these methods were used before and we can always revisit these methods when we've time by checking out a particular commit.