return the user by username . this method should be overridden in concrete implementation . the default implementation always throws an exception . concode_field_sep Logger log concode_elem_sep UserService instance concode_field_sep void init concode_elem_sep String modifyRole concode_elem_sep User login concode_elem_sep String deleteRole concode_elem_sep Role getRoleByName concode_elem_sep User getGuestUser concode_elem_sep User modifyUser concode_elem_sep User modifyUserwithRoles concode_elem_sep void updateUserPassword concode_elem_sep List<User> getUsers concode_elem_sep void setUserPassword concode_elem_sep void deleteUser concode_elem_sep List<User> getUsersWithRoles concode_elem_sep Role insertRole concode_elem_sep User createUser concode_elem_sep User createUser concode_elem_sep UserService getInstance concode_elem_sep void teardown concode_elem_sep String generateUuid concode_elem_sep String generateUuid concode_elem_sep Role[] getRoles concode_elem_sep Role[] getRoles
User function ( String arg0 ) { throw new ServiceException ( "srini_string" ) ; }