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/* * $Id: ModuleUtils.java 471754 2006-11-06 14:55:09Z husted $ * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.util; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.struts.Globals; import org.apache.struts.action.RequestProcessor; import org.apache.struts.config.MessageResourcesConfig; import org.apache.struts.config.ModuleConfig; import javax.servlet.ServletContext; import javax.servlet.http.HttpServletRequest; /** * General purpose utility methods related to module processing. * * @version $Rev: 471754 $ * @since Struts 1.2 */ public class ModuleUtils { /** * The Singleton instance. */ private static final ModuleUtils instance = new ModuleUtils(); /** * Commons logging instance. */ private static final Log log = LogFactory.getLog(ModuleUtils.class); /** * Constructor for ModuleUtils. */ protected ModuleUtils() { super(); } /** * Returns the Singleton instance of TagUtils. */ public static ModuleUtils getInstance() { return instance; } /** * Return the current ModuleConfig object stored in request, if it exists, * null otherwise. This method can be used by plugin to retrieve the * current module config object. If no moduleConfig is found, this means * that the request haven't hit the server throught the struts servlet. * The appropriate module config can be set and found with <code>{@link * ModuleUtils#selectModule(HttpServletRequest, ServletContext)} </code>. * * @param request The servlet request we are processing * @return the ModuleConfig object from request, or null if none is set in * the request. */ public ModuleConfig getModuleConfig(HttpServletRequest request) { return (ModuleConfig) request.getAttribute(Globals.MODULE_KEY); } /** * Return the desired ModuleConfig object stored in context, if it exists, * null otherwise. * * @param prefix The module prefix of the desired module * @param context The ServletContext for this web application * @return the ModuleConfig object specified, or null if not found in the * context. */ public ModuleConfig getModuleConfig(String prefix, ServletContext context) { if ((prefix == null) || "/".equals(prefix)) { return (ModuleConfig) context.getAttribute(Globals.MODULE_KEY); } else { return (ModuleConfig) context.getAttribute(Globals.MODULE_KEY + prefix); } } /** * Return the desired ModuleConfig object stored in context, if it exists, * otherwise return the current ModuleConfig * * @param prefix The module prefix of the desired module * @param request The servlet request we are processing * @param context The ServletContext for this web application * @return the ModuleConfig object specified, or null if not found in the * context. */ public ModuleConfig getModuleConfig(String prefix, HttpServletRequest request, ServletContext context) { ModuleConfig moduleConfig = null; if (prefix != null) { //lookup module stored with the given prefix. moduleConfig = this.getModuleConfig(prefix, context); } else { //return the current module if no prefix was supplied. moduleConfig = this.getModuleConfig(request, context); } return moduleConfig; } /** * Return the ModuleConfig object is it exists, null otherwise. * * @param request The servlet request we are processing * @param context The ServletContext for this web application * @return the ModuleConfig object */ public ModuleConfig getModuleConfig(HttpServletRequest request, ServletContext context) { ModuleConfig moduleConfig = this.getModuleConfig(request); if (moduleConfig == null) { moduleConfig = this.getModuleConfig("", context); request.setAttribute(Globals.MODULE_KEY, moduleConfig); } return moduleConfig; } /** * Get the module name to which the specified request belong. * * @param request The servlet request we are processing * @param context The ServletContext for this web application * @return The module prefix or "" */ public String getModuleName(HttpServletRequest request, ServletContext context) { // Acquire the path used to compute the module String matchPath = (String) request.getAttribute(RequestProcessor.INCLUDE_SERVLET_PATH); if (matchPath == null) { matchPath = request.getServletPath(); } return this.getModuleName(matchPath, context); } /** * Get the module name to which the specified uri belong. * * @param matchPath The uri from which we want the module name. * @param context The ServletContext for this web application * @return The module prefix or "" */ public String getModuleName(String matchPath, ServletContext context) { if (log.isDebugEnabled()) { log.debug("Get module name for path " + matchPath); } String prefix = ""; // Initialize prefix before we try lookup String[] prefixes = getModulePrefixes(context); // Get all other possible prefixes int lastSlash = 0; // Initialize before loop while (prefix.equals("") && ((lastSlash = matchPath.lastIndexOf("/")) > 0)) { // We may be in a non-default module. Try to get it's prefix. matchPath = matchPath.substring(0, lastSlash); // Match against the list of module prefixes for (int i = 0; i < prefixes.length; i++) { if (matchPath.equals(prefixes[i])) { prefix = prefixes[i]; break; } } } if (log.isDebugEnabled()) { log.debug("Module name found: " + (prefix.equals("") ? "default" : prefix)); } return prefix; } /** * Return the list of module prefixes that are defined for this web * application. <strong>NOTE</strong> - the "" prefix for the default * module is not included in this list. * * @param context The ServletContext for this web application. * @return An array of module prefixes. */ public String[] getModulePrefixes(ServletContext context) { return (String[]) context.getAttribute(Globals.MODULE_PREFIXES_KEY); } /** * Select the module to which the specified request belongs, and add * corresponding request attributes to this request. * * @param request The servlet request we are processing * @param context The ServletContext for this web application */ public void selectModule(HttpServletRequest request, ServletContext context) { // Compute module name String prefix = getModuleName(request, context); // Expose the resources for this module this.selectModule(prefix, request, context); } /** * Select the module to which the specified request belongs, and add * corresponding request attributes to this request. * * @param prefix The module prefix of the desired module * @param request The servlet request we are processing * @param context The ServletContext for this web application */ public void selectModule(String prefix, HttpServletRequest request, ServletContext context) { // Expose the resources for this module ModuleConfig config = getModuleConfig(prefix, context); if (config != null) { request.setAttribute(Globals.MODULE_KEY, config); MessageResourcesConfig[] mrConfig = config.findMessageResourcesConfigs(); for (int i = 0; i < mrConfig.length; i++) { String key = mrConfig[i].getKey(); MessageResources resources = (MessageResources) context.getAttribute(key + prefix); if (resources != null) { request.setAttribute(key, resources); } else { request.removeAttribute(key); } } } else { request.removeAttribute(Globals.MODULE_KEY); } } }