Run Vacuum Through JDBC

I was wondering, how can I check whether Vacuum operation had been executed without problem?

I use the following Java code to execute Vacuum operation

final Statement st2 = connection.createStatement();
st2.executeUpdate("VACUUM FULL ANALYZE VERBOSE");
st2.close();

Nothing print out at console.

I check at server status through pgadmin, also get no hint whether Vacuum operation had been executed.

Thanks and Regards
Yan Cheng CHEOK