Add an option to @Field annotation to control property write rules

[divyajnu08]

…on write

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[divyajnu08]

Hi Christoph/Mark

Please find the pull request , I hope it solves the issue , kindly let me know if any comments.
Also I could find only one test case , could you please guide me what are the other test cases need to be changed ?

Thanks

[mp911de]

Thanks for your pull request. It goes already in the right direction.

Looking at the code, I'm wondering whether it would actually make sense to represent null handling with an enumeration. omitNull is a negation of what should happen when writing values and from a wording perspective, I don't have a much more descriptive attribute name that would resolve to boolean.

I suggest expressing what should happen if the value is null along the lines of @Field(write=ALWAYS|NON_NULL) accompanied with an enum Field.Write {ALWAYS,NON_NULL} defaulting to NON_NULL. Anything else (omitNull, onNull) could be viewed from both sides, if the property is null or the field in the document is null/non-existent.

[divyajnu08]

Hi Mark

Kindly find the review comments changes updated on the branch.
Let me know if any other change needs to be done.
Now a field will be annotated as @field(write=Field.Write.ALWAYS|NON_NULL) default NON_NULL.
I have created an enum for write rule.

Thanks

[mp911de]

Thanks a lot. I pushed a polished variant of the changes to https://github.com/spring-projects/spring-data-mongodb/tree/issue/3407

[mp911de]

Thank you for your contribution. That's merged and polished now.