jsonb payload, compression and bandwith usage

Hi,

Currently, I use PgObject to store a document in a jsonb column.

But in my usecase ; network bandwith is limited and jsonb as string is quite heavy. (Between 2-5 Mbyte). 
Something like gzip is very effective to reduce the size of the payload (about 70%).

So is there any support for compression in current jdbc driver ?
If yes, is it active by default ? (I don’t see any option in driver documentation to enable ou disable it).
If no, is there an alternative way to handle it ? (like handling json (de)compression at application level, et create some sort of automatic conversion on postgres side).

Thanks for your attention,
Best Regards,
Yann.