[DRILL-8549] Add Jackson validation of polymorphic types.

[pjfanning]

DRILL-8549: Add Jackson validation of polymorphic types.

Description

Work in Progress. I need to add some tests. I just want to start by seeing if the validation causes unexpected test failures.

Documentation

(Please describe user-visible changes similar to what should appear in the Drill documentation.)

Testing

(Please describe how this PR has been tested.)

[pjfanning]

@cgivre does look like a viable solution or is too risky to add this type of validation? Classes like StatisticsHolder could in theory wrap any T type. The PolymorphicTypeValidator that I added here cover the most obvious use cases but maybe there are some that are not tested in the Drill tests but that users could be relying on?

[cgivre]

@cgivre does look like a viable solution or is too risky to add this type of validation? Classes like StatisticsHolder could in theory wrap any T type. The PolymorphicTypeValidator that I added here cover the most obvious use cases but maybe there are some that are not tested in the Drill tests but that users could be relying on?

I'm honestly not sure. The unit tests all pass which is a good sign. Have you tried building Drill and testing manually? Where I've seen issues are when users update storage plugin configurations but the updates get corrupted.