docs: protected void fail(HttpServletRequest request, HttpServletResponse response, OAuthRequestFailedException failure) throws IOException, ServletException {
  		try {
  			//attempt to set the last exception.
  			request.getSession().setAttribute(OAUTH_FAILURE_KEY, failure);
  		}
  		catch (Exception e) {
  			//fall through....
  		}
  
  		if (LOG.isDebugEnabled()) {
  			LOG.debug(failure);
  		}
  
  		if (getOAuthFailureHandler() != null) {
  			getOAuthFailureHandler().handle(request, response, failure);
  		}
  		else {
  			throw failure;
  		}
  	}