| /* |
| * $Id$ |
| * |
| * 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.webapp.tiles.portal; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import javax.servlet.ServletContext; |
| import javax.servlet.ServletException; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpServletResponse; |
| import javax.servlet.http.HttpSession; |
| |
| 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.tiles.ComponentContext; |
| import org.apache.struts.tiles.ComponentDefinition; |
| import org.apache.struts.tiles.Controller; |
| import org.apache.struts.tiles.DefinitionsUtil; |
| import org.apache.struts.tiles.actions.TilesAction; |
| import org.apache.struts.tiles.beans.MenuItem; |
| |
| /** |
| * This controller load user menu settings and put them in tile context. |
| * If menu settings are not defined for user, defined them based on tiles |
| * attributes used as default. |
| * |
| * This implementation extends Struts Action, and also define Tiles Controller interface. |
| * This allows to use it as well as a controller type or a controller url. If used |
| * as controller type, Struts Action functionality are not availables. |
| * |
| * Tiles input attributes : |
| * <ul> |
| * <li>title : menu title</li> |
| * <li>items : Menu entries used as default when user settings is created</li> |
| * <li>defaultChoice : Menus or menu entries porposed as choice to user</li> |
| * <li>storeUnderName : Store user settings under provided name in session context [optional]</li> |
| * <li></li> |
| * </ul> |
| * Tiles output attributes : |
| * <ul> |
| * <li>title : menu title</li> |
| * <li>items : Menu items to display</li> |
| * <li></li> |
| * </ul> |
| * |
| * @version $Rev$ $Date$ |
| */ |
| public final class UserMenuAction extends TilesAction implements Controller { |
| |
| /** |
| * Commons Logging instance. |
| */ |
| private static Log log = LogFactory.getLog(UserMenuAction.class); |
| |
| /** |
| * Tile attribute containing name used to store user settings in session |
| * context. |
| */ |
| public static String USER_SETTINGS_NAME_ATTRIBUTE = "userSettingsName"; |
| |
| /** |
| * Default name used to store settings in session context. |
| */ |
| public static String DEFAULT_USER_SETTINGS_NAME = |
| "tiles.examples.portal.USER_MENU_SETTINGS"; |
| |
| /** |
| * Default name used to store menu catalog in application scope. |
| */ |
| public static String DEFAULT_MENU_CATALOG_NAME = |
| "tiles.examples.portal.MenuCatalog"; |
| |
| /** |
| * Tile attribute containing name used to store menu catalog in application |
| * scope. |
| */ |
| public static String MENU_CATALOG_NAME_ATTRIBUTE = "catalogName"; |
| |
| /** |
| * Tile attribute containing name of the settings definition used to |
| * initialize catalog. |
| */ |
| public static final String CATALOG_SETTING_ATTRIBUTE = "catalogSettings"; |
| |
| /** |
| * Tile attribute containing items to render. |
| */ |
| public static String USER_ITEMS_ATTRIBUTE = "items"; |
| |
| /** |
| * Struts' action perform(). |
| * Process the specified HTTP request, and create the corresponding HTTP |
| * response (or forward to another web component that will create it). |
| * Return an <code>ActionForward</code> instance describing where and how |
| * control should be forwarded, or <code>null</code> if the response has |
| * already been completed. |
| * |
| * @param context The current Tile context, containing Tile attributes. |
| * @param mapping The ActionMapping used to select this instance. |
| * @param form The optional ActionForm bean for this request (if any). |
| * @param request The HTTP request we are processing. |
| * @param response The HTTP response we are creating. |
| * |
| * @exception Exception if the application business logic throws |
| * an exception |
| * @since Struts 1.1 |
| */ |
| public ActionForward execute( |
| ComponentContext context, |
| ActionMapping mapping, |
| ActionForm form, |
| HttpServletRequest request, |
| HttpServletResponse response) |
| throws Exception { |
| |
| this.execute( |
| context, |
| request, |
| response, |
| getServlet().getServletContext()); |
| |
| return null; |
| } |
| |
| /** |
| * Method associated to a tile and called immediately before tile is included. |
| * @param tileContext Current tile context. |
| * @param request Current request |
| * @param response Current response |
| * @param servletContext Current servlet context |
| */ |
| public void perform( |
| ComponentContext context, |
| HttpServletRequest request, |
| HttpServletResponse response, |
| ServletContext servletContext) |
| throws ServletException, IOException { |
| |
| log.debug("Enter action UserMenuAction"); |
| |
| // Load user settings from user context |
| MenuSettings settings = getUserSettings(request, context); |
| |
| // Set parameters for rendering page |
| context.putAttribute(USER_ITEMS_ATTRIBUTE, settings.getItems()); |
| |
| log.debug("settings=" + settings); |
| log.debug("Exit action UserMenuAction"); |
| |
| } |
| |
| /** |
| * Load user setting. |
| * This implementation load setting from user context. |
| * If settings are not found, initialized them from default items defined |
| * in Tile's context. |
| * If settings are not found, initialized them. |
| */ |
| public static MenuSettings getUserSettings( |
| HttpServletRequest request, |
| ComponentContext context) |
| throws ServletException { |
| |
| // Get current session. |
| HttpSession session = request.getSession(); |
| |
| // Retrieve attribute name used to store settings. |
| String userSettingsName = |
| (String) context.getAttribute(USER_SETTINGS_NAME_ATTRIBUTE); |
| |
| if (userSettingsName == null) { |
| userSettingsName = DEFAULT_USER_SETTINGS_NAME; |
| } |
| |
| // Get user list from user context |
| MenuSettings settings = |
| (MenuSettings) session.getAttribute(userSettingsName); |
| |
| // If settings don't exist, create and initialize them |
| // Initialization is done from context attribute denoted by ITEMS |
| if (settings == null) { |
| // List doesn't exist, create it and initialize it from Tiles parameters |
| settings = new MenuSettings(); |
| try { |
| settings.addItems( |
| (List) context.getAttribute(USER_ITEMS_ATTRIBUTE)); |
| } catch (ClassCastException ex) { |
| throw new ServletException("Can't initialize user menu : default items must be a list of items"); |
| } |
| |
| // Save user settings in session |
| session.setAttribute(userSettingsName, settings); |
| } |
| |
| return settings; |
| } |
| |
| /** |
| * Get catalog of available menu entries. |
| * This implementation creates catalog list from the provided menu bar |
| * entries. |
| */ |
| public static List getCatalog( |
| ComponentContext context, |
| HttpServletRequest request, |
| ServletContext servletContext) |
| throws ServletException { |
| |
| // Retrieve name used to store catalog in application context. |
| // If not found, use default name |
| String catalogName = |
| (String) context.getAttribute(MENU_CATALOG_NAME_ATTRIBUTE); |
| |
| if (catalogName == null) { |
| catalogName = DEFAULT_MENU_CATALOG_NAME; |
| } |
| |
| // Get catalog from context |
| List catalog = (List) servletContext.getAttribute(catalogName); |
| |
| // If not found, initialize it from provided default menu |
| if (catalog == null) { |
| Object menuBar = context.getAttribute(CATALOG_SETTING_ATTRIBUTE); |
| if (menuBar == null) { |
| throw new ServletException( |
| "Attribute '" |
| + CATALOG_SETTING_ATTRIBUTE |
| + "' must be set. It define entries used in catalog"); |
| } |
| |
| catalog = new ArrayList(); |
| extractItems(catalog, menuBar, request, servletContext); |
| if (catalog.size() == 0) { |
| throw new ServletException("Can't initialize menu items catalog"); |
| } |
| |
| // save it for future use |
| servletContext.setAttribute(catalogName, catalog); |
| } |
| |
| return catalog; |
| } |
| |
| /** |
| * Extract menu items from passed object. Items are stored in |
| * <code>result</code> parameter. |
| * This method allows to create a list of menu entries from existing menus. |
| * Check object type class : |
| * <li> |
| * <ul>MenuItems : add it</ul> |
| * <ul>ComponentDefinition : get attribute items, or list if not found. |
| * Call ExtractItems with resulting attribute. |
| * </ul> |
| * <ul>List : iterate on list, and call ExtractItems for each element. |
| * </li> |
| * @param result result list (should be initialized) |
| * @param object object to add (MenuItems, Definition, ...) |
| * @param request current request |
| * @param servletContext current servlet context. |
| */ |
| private static void extractItems( |
| List result, |
| Object object, |
| HttpServletRequest request, |
| ServletContext servletContext) { |
| |
| log.debug("Extract menu item from '" + object + "'"); |
| |
| if (object instanceof String) { // definition name |
| try { |
| ComponentDefinition def = |
| DefinitionsUtil.getDefinition( |
| (String) object, |
| request, |
| servletContext); |
| |
| extractItems(result, def, request, servletContext); |
| |
| } catch (Exception ex) { // silently fail |
| } |
| |
| } else if (object instanceof List) { |
| List list = (List) object; |
| Iterator iter = list.iterator(); |
| while (iter.hasNext()) { |
| extractItems(result, iter.next(), request, servletContext); |
| } |
| |
| } else if (object instanceof ComponentDefinition) { |
| ComponentDefinition definition = (ComponentDefinition) object; |
| Object attribute = definition.getAttribute("items"); |
| if (attribute == null) { |
| attribute = definition.getAttribute("list"); |
| } |
| |
| if (attribute == null) { |
| return; |
| } |
| |
| extractItems(result, attribute, request, servletContext); |
| |
| } else if (object instanceof MenuItem) { |
| result.add(object); |
| } |
| } |
| |
| /** |
| * @see org.apache.struts.tiles.Controller#execute(org.apache.struts.tiles.ComponentContext, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, javax.servlet.ServletContext) |
| */ |
| public void execute( |
| ComponentContext tileContext, |
| HttpServletRequest request, |
| HttpServletResponse response, |
| ServletContext servletContext) |
| throws Exception { |
| |
| log.debug("Enter action UserMenuAction"); |
| |
| // Load user settings from user context |
| MenuSettings settings = getUserSettings(request, tileContext); |
| |
| // Set parameters for rendering page |
| tileContext.putAttribute(USER_ITEMS_ATTRIBUTE, settings.getItems()); |
| |
| log.debug("settings=" + settings); |
| log.debug("Exit action UserMenuAction"); |
| |
| } |
| |
| } |