Add isOverridden, update Java pojo with setter for parent properties

[wing328]

• Add isOverridden to indicate a property (in allVars) belongs to the parent model
• update Java pojo with setter for parent properties

To close #14915

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cc @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10)

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[devhl-labs]

Can't you get the same information from isInherited and isNew?

[wing328]

tried these 2 but looks like these 2 attributes only work in certain generators.

tried to fix/add these 2 attributes in default codegen but that results in a lot of change in samples that I do not have time to go over one by one.

[Willem1987]

@wing328 Im having trouble with thing change, but i don't know if it is misusage or a bug.

I tried sharing a class along modules and have a multi layered model(base, extend1, extend 2, dto).
When using importmapping the isOverriden sees properties as Overridden and adds @OverRide, while the direct superclass does not have a similar builder/setter method.

Id rather not have custom templates that I need to keep in line. Would it be possible to use the imported class to check whether to add @OverRide on the child method or somehow avoid the whole builder method effect?

I'd be willing to put in some work for a PR. For now i seemed to workaround it leaving all the properties in the child class but that feels like a lot of duplication for an allof structure.