FLINK-4462 Add RUN_TIME retention policy for all the flink annotations

[ramkrish86]

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(Ram)

[StephanEwen]

Is that needed? The japicmp plugin can work with the annotations without runtime retention. Would be great if that plugin can check the presence of annotations, that seems like the right place.

[ramkrish86]

Would be great if that plugin can check the presence of annotations, that seems like the right place.

I see. I have not worked with 'japicmp'. My intention was to use plain java reflection APIs

Annotation[] anns = c.getDeclaredAnnotations();

I can see if the same can be done with the 'japicmp' too. And if so will close this PR. Thanks @StephanEwen .

[ramkrish86]

Is 'jApiCmp' added in class path? I am not able to see the API/Interfaces exposed. Trying to make use of it.

[StephanEwen]

The japicmp is a maven plugin that is added to projects like flink-core. It is not part of any code.

[ramkrish86]

@StephanEwen
I meant the library only. I did not mean it is added in code. Am not sure what are the APIs in that library to make use.

[ramkrish86]

@StephanEwen
As said above am not sure how to use the japicmp library. I can see that from the IDE am not able to use any of the APIs provided from the library. May be am missing something?
Also reading the docs of japicmp it says how to pass two different versions of a jar file and see what are the public interface differences. So am not sure how japicmp internally does it.
Do you have an problem in adding this RUN_TIME annotation? I think it helps in adding plain java reflection based utils to idenfity classes/interfaces missing them.
I can update my PR based on your thoughts on jaipcmp usage.