Java tutorial
/******************************************************************************* * Copyright (c) 2010-2014 SAP AG and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * SAP AG - initial API and implementation *******************************************************************************/ package org.eclipse.skalli.view.internal.servlet; import java.io.IOException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang.StringUtils; public class AuthenticationServlet extends HttpServlet { private static final long serialVersionUID = -6622092406596651354L; private static final String JSP_LOGIN = "/search/login.jsp"; //$NON-NLS-1$ private static final String PARAM_RETURNURL = "returnUrl"; //$NON-NLS-1$ @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { if (request.getUserPrincipal() != null) { // principal provided, go back to calling page String returnUrl = (String) request.getParameter(PARAM_RETURNURL); if (StringUtils.isBlank(returnUrl)) { returnUrl = "/"; //$NON-NLS-1$ } response.sendRedirect(returnUrl); } else { ServletContext context = getServletContext(); RequestDispatcher dispatcher = context.getRequestDispatcher(JSP_LOGIN); dispatcher.forward(request, response); } } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doGet(req, resp); } }