/** Initialize user listing from database
*
*/
protected void getUserListing(Connection connection) throws SQLException {
_users = new UserListing();
Statement stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM " + RelationUser);
while (rs.next()) {
_users.add(new User(rs.getInt(RelUserColID), rs.getString(RelUserColLogin), rs.getString(RelUserColFullName), rs.getString(RelUserColPassword)));
}