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/* * Copyright 2003,2004 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.chain; import org.apache.commons.chain.Command; import org.apache.commons.chain.Context; import org.apache.commons.chain.web.WebContext; import org.apache.struts.Globals; import org.apache.struts.chain.Constants; import org.apache.struts.config.ModuleConfig; import org.apache.struts.util.MessageResources; /** * <p>Cache the <code>ModuleConfig</code> and <code>MessageResources</code> * instances for the sub-application module to be used for processing * this request.</p> * * @author Craig R. McClanahan * @version $Rev: 54933 $ $Date: 2004-10-16 18:04:52 +0100 (Sat, 16 Oct 2004) $ */ public abstract class AbstractSelectModule implements Command { // ------------------------------------------------------ Instance Variables private String messageResourcesKey = Constants.MESSAGE_RESOURCES_KEY; private String moduleConfigKey = Constants.MODULE_CONFIG_KEY; // -------------------------------------------------------------- Properties /** * <p>Return the context attribute key under which the default * <code>MessageResources</code> for the currently selected application * module will be stored.</p> */ public String getMessageResourcesKey() { return (this.messageResourcesKey); } /** * <p>Set the context attribute key under which the default * <code>MessageResources</code> for the currently selected application * module will be stored.</p> * * @param messageResourcesKey The new context attribute key */ public void setMessageResourcesKey(String messageResourcesKey) { this.messageResourcesKey = messageResourcesKey; } /** * <p>Return the context attribute key under which the * <code>ModuleConfig</code> for the currently selected application * module will be stored.</p> */ public String getModuleConfigKey() { return (this.moduleConfigKey); } /** * <p>Set the context attribute key under which the * <code>ModuleConfig</code> for the currently selected application * module will be stored.</p> * * @param moduleConfigKey The new context attribute key */ public void setModuleConfigKey(String moduleConfigKey) { this.moduleConfigKey = moduleConfigKey; } // ---------------------------------------------------------- Public Methods /** * <p>Cache the <code>ModuleConfig</code> and <code>MessageResources</code> * instances for the sub-application module to be used for processing * this request.</p> * * @param context The <code>Context</code> for the current request * * @exception IllegalArgumentException if no valid * ModuleConfig or MessageResources can be identified for this request * * @return <code>false</code> so that processing continues */ public boolean execute(Context context) throws Exception { // Identify the module prefix for the current module String prefix = getPrefix(context); // Cache the corresponding ModuleConfig and MessageResources instances WebContext wcontext = (WebContext) context; ModuleConfig moduleConfig = (ModuleConfig) wcontext.getApplicationScope().get(Globals.MODULE_KEY + prefix); if (moduleConfig == null) { throw new IllegalArgumentException("No module config for prefix '" + prefix + "'"); } wcontext.put(getModuleConfigKey(), moduleConfig); wcontext.getRequestScope().put(Globals.MODULE_KEY, moduleConfig); MessageResources messageResources = (MessageResources) wcontext.getApplicationScope() .get(Globals.MESSAGES_KEY + prefix); if (messageResources != null) { wcontext.put(getMessageResourcesKey(), messageResources); wcontext.getRequestScope().put(Globals.MESSAGES_KEY, messageResources); } return (false); } // ------------------------------------------------------- Protected Methods /** * <p>Calculate and return the module prefix for the module to be * selected for this request.</p> * * @param context The <code>Context</code> for this request * * @exception IllegalArgumentException if no valid * ModuleConfig or MessageResources can be identified for this request */ protected abstract String getPrefix(Context context); }