Hi Laura,

A similar question was posed recently:
https://lists.lfaidata.foundation/g/janusgraph-users/message/5986

So,
1. Only for the CompositeIndex
2. In your specific example, you could use the java Integer class ( https://docs.oracle.com/javase/8/docs/api/java/lang/Integer.html ), because its constructor takes either integer type or string type and it has the equals() method implemented.

Best wishes,    Marc