code: public String buildOAuthUrl(ConnectionFactory<?> connectionFactory, NativeWebRequest request, MultiValueMap<String, String> additionalParameters) {
  		if (connectionFactory instanceof OAuth1ConnectionFactory) {
  			return buildOAuth1Url((OAuth1ConnectionFactory<?>) connectionFactory, request, additionalParameters);
  		} else if (connectionFactory instanceof OAuth2ConnectionFactory) {
  			return buildOAuth2Url((OAuth2ConnectionFactory<?>) connectionFactory, request, additionalParameters);
  		} else {
  			throw new IllegalArgumentException("ConnectionFactory not supported");
  		}		
  	}
docs: Builds the provider URL to redirect the user to for connection authorization.
  @param connectionFactory the service provider's connection factory e.g. FacebookConnectionFactory
  @param request the current web request
  @param additionalParameters parameters to add to the authorization URL.
  @return the URL to redirect the user to for authorization
  @throws IllegalArgumentException if the connection factory is not OAuth1 based.