private static Node checkUserIdentifier(final HttpServletRequest request,
			final DeleteFollowResponse response) {
		final String userId = request
				.getParameter(ProtocolConstants.Parameters.Delete.Follow.USER_IDENTIFIER);
		if (userId != null) {
			final Node user = NeoUtils.getUserByIdentifier(userId);
			if (user != null) {
				return user;
			}
			response.userIdentifierInvalid(userId);
		} else {
			response.userIdentifierMissing();
		}

		return null;
	}
private static Node checkUserIdentifier ( final HttpServletRequest request , final DeleteFollowResponse response ) { final String userId = request . getParameter ( ProtocolConstants . Parameters . Delete . Follow . USER_IDENTIFIER ) ; if ( userId != null ) { final Node user = NeoUtils . getUserByIdentifier ( userId ) ; if ( user != null ) { return user ; } response . userIdentifierInvalid ( userId ) ; } else { response . userIdentifierMissing ( ) ; } return null ; }
check if the request contains a valid user identifier

@param request
Tomcat servlet request
@param response
response object
@return user node with the identifier passed<br>
<b>null</b> if the identifier is invalid