Issue #547: Field level POJO accessors

[mgreenwood1001]

Immutable entity support (#547) - I could see using a pattern where-in the domain entity is immutable for "store" behavior. Although, it seems unlikely as the predominate case as I'd likely have some form of transfer object to marshal state to/from the DB where-in I have setters/getters.

Just an option for an implementation that solves this concern as I myself might want to do something similar in some of our use-cases.

Thought this was an interesting problem to solve, here's one possible implementation. Might consider re-using reflectutils rather than directly using java.lang.*... Also might not want to invoke field.set when setter not available...

Tests are needed by this implementation, willing to add them if this is worthy of eventually merging.

[millems]

Sorry for the delay on this.

We've got immutable model support as the first suggestion for V2 of the mapper: aws/aws-sdk-java-v2#35

We're mostly code frozen on major features being added to 1.11.x's mapper. We'll make sure to think about this problem as we redesign V2. Sorry we weren't able to integrate your contribution. We appreciate it.