Java tutorial
/* * JBoss, Home of Professional Open Source * Copyright 2013, Red Hat, Inc. and/or its affiliates, and individual * contributors by the @authors tag. See the copyright.txt in the * distribution for a full listing of individual contributors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * http://www.apache.org/licenses/LICENSE-2.0 * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.gatein.security.oauth.portlet.twitter; import java.io.IOException; import javax.portlet.PortletContext; import javax.portlet.PortletException; import javax.portlet.PortletRequestDispatcher; import javax.portlet.RenderRequest; import javax.portlet.RenderResponse; import org.gatein.api.oauth.OAuthProvider; import org.gatein.security.oauth.portlet.OAuthPortletFilter; import twitter4j.TwitterException; /** * Wrapper against some operation call to Twitter backend. It provides especially error handling functionality * * @author <a href="mailto:mposolda@redhat.com">Marek Posolda</a> */ public abstract class TwitterPortletRequest<T> { private final RenderRequest request; private final RenderResponse response; private final PortletContext portletContext; private final OAuthProvider oauthProvider; public TwitterPortletRequest(RenderRequest request, RenderResponse response, PortletContext portletContext, OAuthProvider oauthProvider) { this.request = request; this.response = response; this.portletContext = portletContext; this.oauthProvider = oauthProvider; } protected abstract T invokeRequest() throws TwitterException; public T executeRequest() throws IOException, PortletException { try { return invokeRequest(); } catch (TwitterException te) { String jspErrorPage; if (te.getStatusCode() == 401) { request.setAttribute(OAuthPortletFilter.ATTRIBUTE_ERROR_MESSAGE, "Twitter access token is invalid."); request.setAttribute(OAuthPortletFilter.ATTRIBUTE_OAUTH_PROVIDER, oauthProvider); jspErrorPage = "/jsp/error/token.jsp"; } else { request.setAttribute(OAuthPortletFilter.ATTRIBUTE_ERROR_MESSAGE, getErrorMessage(te)); jspErrorPage = "/jsp/error/error.jsp"; } System.err.println(getErrorMessage(te)); PortletRequestDispatcher prd = portletContext.getRequestDispatcher(jspErrorPage); prd.include(request, response); } return null; } private String getErrorMessage(TwitterException te) { String errorMessage = "Twitter error occured. StatusCode: " + te.getStatusCode() + ", Details: " + te.getMessage(); if (te.getCause() != null) { errorMessage = errorMessage + ", Cause: " + te.getCause(); } return errorMessage; } }