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/* * $Id: BaseAction.java 360442 2005-12-31 20:10:04Z husted $ * * Copyright 1999-2004 The Apache Software Foundation. * * 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.apache.struts.apps.mailreader.actions; import org.apache.commons.beanutils.PropertyUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.struts.action.ActionForm; import org.apache.struts.action.ActionForward; import org.apache.struts.action.ActionMapping; import org.apache.struts.action.ActionMessage; import org.apache.struts.action.ActionMessages; import org.apache.struts.action.DynaActionForm; import org.apache.struts.actions.MappingDispatchAction; import org.apache.struts.apps.mailreader.Constants; import org.apache.struts.apps.mailreader.dao.ExpiredPasswordException; import org.apache.struts.apps.mailreader.dao.Subscription; import org.apache.struts.apps.mailreader.dao.User; import org.apache.struts.apps.mailreader.dao.UserDatabase; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; /** * <p> * Base Action for MailReader application. * </p><p> * All the BaseAction helper methods are prefixed with "do" * so that they can be easily distinguished from Struts and Servlet API methods. * BaseAction subclasses may also have prive "do" helpers of their own. * </p><p> * Methods are kept in alphabetical order, to make them easier to find. * </p> * * @version $Rev: 360442 $ $Date: 2005-12-31 13:10:04 -0700 (Sat, 31 Dec 2005) $ */ public abstract class BaseAction extends MappingDispatchAction { // ---- Fields ---- /** * <p> * Name of username field ["username"]. * </p> */ public static String USERNAME = "username"; /** * <p> * Name of password field ["password"]. * </p> */ public static String PASSWORD = "password"; /** * <p> * Name of task field ["task"]. * </p> */ public final static String TASK = "task"; // ---- Protected Variables ---- /** * <p> * The <code>Log</code> instance for this application. * </p> */ protected Log log = LogFactory.getLog(Constants.PACKAGE); // ---- Protected Methods ---- /** * <p> * Store User object in client session. * If user object is null, any existing user object is removed. * </p> * * @param request The request we are processing * @param user The user object returned from the database */ void doCacheUser(HttpServletRequest request, User user) { HttpSession session = request.getSession(); session.setAttribute(Constants.USER_KEY, user); if (log.isDebugEnabled()) { log.debug("LogonAction: User '" + user.getUsername() + "' logged on in session " + session.getId()); } } /** * <p> * Helper method to log event and cancel transaction. * </p> * * @param session Our HttpSession * @param method Method being processed * @param key Attrkibute to remove from session, if any */ protected void doCancel(HttpSession session, String method, String key) { if (log.isTraceEnabled()) { StringBuffer sb = new StringBuffer(128); sb.append(Constants.LOG_CANCEL); sb.append(method); log.trace(sb.toString()); } if (key != null) { session.removeAttribute(key); } } /** * <p> * Return the local or global forward named "failure" * or null if there is no such forward. * </p> * * @param mapping Our ActionMapping * @return Return the mapping named "failure" or null if there is no such mapping. */ protected ActionForward doFindFailure(ActionMapping mapping) { if (log.isTraceEnabled()) { log.trace(Constants.LOG_FAILURE); } return mapping.findForward(Constants.FAILURE); } /** * <p> * Return the local or global forward named "logon" * or null if there is no such forward. * </p> * * @param mapping Our ActionMapping * @return Return the mapping named "logon" or null if there is no such mapping. */ protected ActionForward doFindLogon(ActionMapping mapping) { if (log.isTraceEnabled()) { log.trace(Constants.LOG_LOGON); } return mapping.findForward(Constants.LOGON); } /** * <p> * Return the mapping labeled "success" * or null if there is no such mapping. * </p> * * @param mapping Our ActionMapping * @return Return the mapping named "success" or null if there is no such * mapping. */ protected ActionForward doFindSuccess(ActionMapping mapping) { if (log.isTraceEnabled()) { log.trace(Constants.LOG_SUCCESS); } return mapping.findForward(Constants.SUCCESS); } /** * <p> * Helper method to fetch a String property from a DynaActionForm. * </p> * <p> * Values are returned trimmed of leading and trailing whitespace. * Zero-length strings are returned as null. * </p> * * @param form Our DynaActionForm * @param property The name of the property * @return The value or null if an error occurs */ protected String doGet(ActionForm form, String property) { String initial; try { initial = (String) PropertyUtils.getSimpleProperty(form, property); } catch (Throwable t) { initial = null; } String value = null; if ((initial != null) && (initial.length() > 0)) { value = initial.trim(); if (value.length() == 0) { value = null; } } return value; } /** * <p> * Obtain the cached Subscription object, if any. * </p> * * @param session Our HttpSession * @return Cached Subscription object or null */ protected Subscription doGetSubscription(HttpSession session) { return (Subscription) session.getAttribute(Constants.SUBSCRIPTION_KEY); } /** * <p> * Obtain the cached Subscription object, if any. * </p> * * @param request Our HttpServletRequest * @return Cached Subscription object or null */ protected Subscription doGetSubscription(HttpServletRequest request) { HttpSession session = request.getSession(); return doGetSubscription(session); } /** * <p> * Confirm user credentials. Post any errors and return User object * (or null). * </p> * * @param database Database in which to look up the user * @param username Username specified on the logon form * @param password Password specified on the logon form * @param errors ActionMessages queue to passback errors * @return Validated User object or null * @throws org.apache.struts.apps.mailreader.dao.ExpiredPasswordException * to be handled by Struts exception * processor via the action-mapping */ User doGetUser(UserDatabase database, String username, String password, ActionMessages errors) throws ExpiredPasswordException { User user = null; if (database == null) { errors.add(ActionMessages.GLOBAL_MESSAGE, new ActionMessage("error.database.missing")); } else { if (username.equals("Hermes")) { throw new ExpiredPasswordException("Hermes"); } user = database.findUser(username); if ((user != null) && !user.getPassword().equals(password)) { user = null; } if (user == null) { errors.add(ActionMessages.GLOBAL_MESSAGE, new ActionMessage("error.password.mismatch")); } } return user; } /** * <p> * Confirm user credentials. Post any errors and return User object * (or null). * </p> * * @param username Username specified on the logon form * @param password Password specified on the logon form * @param errors ActionMessages queue to passback errors * @return Validated User object or null * @throws org.apache.struts.apps.mailreader.dao.ExpiredPasswordException * to be handled by Struts exception * processor via the action-mapping */ User doGetUser(String username, String password, ActionMessages errors) throws ExpiredPasswordException { return doGetUser(doGetUserDatabase(), username, password, errors); } /** * <p> * Return a reference to the UserDatabase * or null if the database is not available. * </p> * * @return a reference to the UserDatabase or null if the database is not * available */ protected UserDatabase doGetUserDatabase() { return (UserDatabase) servlet.getServletContext().getAttribute(Constants.DATABASE_KEY); } /** * <p> * Helper method to obtain User form session (if any). * </p> * * @param session Our HttpSession * @return User object, or null if there is no user. */ protected User doGetUser(HttpSession session) { return (User) session.getAttribute(Constants.USER_KEY); } /** * <p> * Helper method to obtain User form session (if any). * </p> * * @param request Our HttpServletRequest * @return User object, or null if there is no user. */ protected User doGetUser(HttpServletRequest request) { HttpSession session = request.getSession(); return (User) session.getAttribute(Constants.USER_KEY); } /** * <p> * Save any errors and the transactioonal token, and forward to the * InputForard result. * </p> * * @param mapping Our ActionMapping * @param request Our HttpServletRequest * @param errors Our ActionMessages collectoin * @return The InputForward for this mappintg */ protected ActionForward doInputForward(ActionMapping mapping, HttpServletRequest request, ActionMessages errors) { this.saveErrors(request, errors); this.saveToken(request); return (mapping.getInputForward()); } /** * <p> * Log a "processing" message for an Action. * </p> * * @param mapping Our ActionMapping * @param method Name of method being processed */ protected void doLogProcess(ActionMapping mapping, String method) { if (log.isDebugEnabled()) { StringBuffer sb = new StringBuffer(128); sb.append(" "); sb.append(mapping.getPath()); sb.append(":"); sb.append(Constants.LOG_PROCESSING); sb.append(method); log.debug(sb.toString()); } } /** * <p> * Helper method to log event and save token. * </p> * * @param request Our HttpServletRequest */ protected void doSaveToken(HttpServletRequest request) { if (log.isTraceEnabled()) { log.trace(Constants.LOG_TOKEN); } saveToken(request); } /** * <p> * Persist the User object, including subscriptions, to the database. * </p> * * @param user Our User object * @throws javax.servlet.ServletException On any error */ protected void doSaveUser(User user) throws ServletException { final String LOG_DATABASE_SAVE_ERROR = " Unexpected error when saving User: "; try { UserDatabase database = doGetUserDatabase(); database.save(); } catch (Exception e) { String message = LOG_DATABASE_SAVE_ERROR + user.getUsername(); log.error(message, e); throw new ServletException(message, e); } } /** * <p> * Helper method to inject a String property into a DynaActionForm. * </p> * * @param form Our DynaActionForm * @param property The name of the property * @param value The value for the property * @return True if the assignment succeeds */ protected boolean doSet(ActionForm form, String property, String value) { try { DynaActionForm dyna = (DynaActionForm) form; dyna.set(property, value); } catch (Throwable t) { return false; } return true; } }