org.apache.struts.tiles.actions.DefinitionDispatcherAction Maven / Gradle / Ivy
/*
* $Id: DefinitionDispatcherAction.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.tiles.actions;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.tiles.ComponentDefinition;
import org.apache.struts.tiles.DefinitionsFactoryException;
import org.apache.struts.tiles.DefinitionsUtil;
import org.apache.struts.tiles.FactoryNotFoundException;
import org.apache.struts.tiles.NoSuchDefinitionException;
import org.apache.struts.tiles.TilesUtil;
/**
* An Action that dispatches to a Tiles Definition
* that is named by the request parameter whose name is specified
* by the parameter property of the corresponding
* ActionMapping.
* This action is useful in following situations:
*
* To associate an Url to a definition
* To use Struts <html:link> tag on a definition
*
* To configure the use of this action in your
* struts-config.xml file, create an entry like this:
*
*
* <action path="/saveSubscription"
* type="org.apache.struts.tiles.actions.DefinitionDispatcherAction"
* parameter="def"/>
* <forward name="success" path="anything" //>
* <forward name="error" path="path.to.error.page" //>
*
*
* which will use the value of the request parameter named "def"
* to pick the appropriate definition name.
*
The value for success doesn't matter. The forward will forward to
* appropriate definition.
*
The value for error should denote a valid jsp path or definition name.
*
* @version $Rev: 471754 $ $Date: 2006-11-06 08:55:09 -0600 (Mon, 06 Nov 2006) $
*/
public class DefinitionDispatcherAction extends Action {
/**
* Commons Logging instance.
*/
protected static Log log = LogFactory.getLog(DefinitionDispatcherAction.class);
/**
* Process the specified HTTP request, and create the corresponding HTTP
* response (or forward to another web component that will create it),
* with provision for handling exceptions thrown by the business logic.
*
* @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(
ActionMapping mapping,
ActionForm form,
HttpServletRequest request,
HttpServletResponse response)
throws Exception {
// Identify the request parameter containing the method name
// If none defined, use "def"
String parameter = mapping.getParameter();
if (parameter == null) {
parameter = "def";
}
// Identify the method name to be dispatched to
String name = request.getParameter(parameter);
if (name == null) {
log.error("Can't get parameter '" + parameter + "'.");
return mapping.findForward("error");
}
// Try to dispatch to requested definition
try {
// Read definition from factory, but we can create it here.
ComponentDefinition definition =
TilesUtil.getDefinition(
name,
request,
getServlet().getServletContext());
if (log.isDebugEnabled()) {
log.debug("Get Definition " + definition);
}
DefinitionsUtil.setActionDefinition(request, definition);
} catch (FactoryNotFoundException e) {
log.error("Can't get definition factory.", e);
return mapping.findForward("error");
} catch (NoSuchDefinitionException e) {
log.error("Can't get definition '" + name + "'.", e);
return mapping.findForward("error");
} catch (DefinitionsFactoryException e) {
log.error("General Factory error '" + e.getMessage() + "'.", e);
return mapping.findForward("error");
} catch (Exception e) {
log.error("General error '" + e.getMessage() + "'.", e);
return mapping.findForward("error");
}
return mapping.findForward("success");
}
/**
* @deprecated This will be removed after Struts 1.2.
*/
protected void printError(HttpServletResponse response, String msg)
throws IOException {
response.setContentType("text/plain");
PrintWriter writer = response.getWriter();
writer.println(msg);
writer.flush();
writer.close();
}
}