java,qadev: remove unused parameters and local vars

Change-Id: Ifb9f9374051fe88dc4cd5a7a28b2c8c992ced873
Reviewed-on: https://gerrit.libreoffice.org/13097
Tested-by: LibreOffice gerrit bot <gerrit@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>