Does Oracle's XMLType support JDBC batch updates?
Does Oracle's JDBC implementation support XMLType batch updates (via PreparedStatement.addBatch())?
I don't think Oracle types can tell how they're invoked, so the answer would be "yes".
The real question is: "What problem do you think that batch processing will introduce that real-time processing does not?"
After a lot of research, it appears like a known limitation of Oracle's JDBC implementation is that it does not support "stream types" as bind variables (XMLType being a stream type).
According to their own documentation:
Oracle's implementation of standard update batching does not support stream types as bind values. (This is also true of Oracle update batching.) Any attempt to use stream types will result in an exception.