Major Description
Changing the username and/or the password seems to have no effect (also confirmed here: https://cwiki.apache.org/Hive/hivejdbcinterface.html).
Connection con = DriverManager.getConnection("jdbc:hive://localhost:10000/default", "", "");
Would be beneficial to pass the username/password via JDBC - and also for the server to honor the username password being passed (may be dependent of that being fixed first).