[FEATURE] equals/hashCode on API objects

[ginkel]

Is your feature request related to a problem?

While developing unit tests for code that makes use of opensearch-java we noticed that the invocations are pretty hard to mock/verify (e.g., using Mockito) as the API objects do not implement equals/hashCode. This causes the effect that it is very hard to verify that a method has been invoked with a certain API object as its argument just uses Object.equals for its equals implementation.

What solution would you like?

Implement equals/hashCode on all API POJOs.

[wbeckler]

This makes sense. Feel free to submit a PR.

[ginkel]

I think as with #298 this doesn't make much sense w/o working code generation, does it?

[miguel-vila]

I see that there is some code generation already, is adding the equals/hashCode methods a possibility now?

[Xtansia]

equals & hashCode are now generated on all codegen'd POJOs, this covers the majority of types in v3.0.0, with a handful of not yet generated classes currently still missing implementations.