Postgresql - COPY TO - get number row inserted - from JDBC

Hello !

My goal is to get the result from "COPY TO ..." query, from JDBC. This
query returns : COPY X
(where X is number line inserted)
1) Can I can I consider it useless, since when no error, all lines are
suposed to be inserted ?
2) If not useless, how can I get the response "COPY 10" (when 10 rows
inserted), I get with psql way, or with pgadmin.

I have tried the int Statement.executeUpdate() method, but it returns 0

Thanks for any help !

Nicolas PARIS