As indicated in
DATAMONGO-241 it would be cool if we could support complex types as Map key types.
A few key points to consider:
- complex key types require completely different storing (BasicDBList of BasicDBObject instances)
- the inner BasicDBObject instances need keys to store key and value of the map entries, these should be configurable
- we have to support scenarios where data in that custom format is read and written with custom converters being registered for the complex key type (which essentially result in a migration back to simple BasicDBObject instances
- indexing metadata