/*
* $Id: TilesDispatchServlet.java 658802 2008-05-21 18:30:50Z apetrelli $
*
* 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.tiles.web.util;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tiles.TilesContainer;
import org.apache.tiles.AttributeContext;
import org.apache.tiles.access.TilesAccess;
import org.apache.tiles.web.startup.TilesListener;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
/**
* Tiles dispatching servlet. Used to invoke
* a definition directly.
*/
public class TilesDispatchServlet extends HttpServlet {
/**
* The logging object.
*/
private static final Log LOG =
LogFactory.getLog(TilesDispatchServlet.class);
/**
* The key under which the container is stored.
*/
private String containerKey;
/**
* The object that will mutate the attribute context so that it uses
* different attributes.
*/
private AttributeContextMutator mutator;
/** {@inheritDoc} */
public void init() throws ServletException {
super.init();
containerKey = getServletConfig().getInitParameter(
TilesListener.CONTAINER_KEY_INIT_PARAMETER);
String temp = getInitParameter("mutator");
if (temp != null) {
try {
mutator = (AttributeContextMutator) Class.forName(temp)
.newInstance();
} catch (Exception e) {
throw new ServletException("Unable to instantiate specified context mutator.", e);
}
} else {
mutator = new DefaultMutator();
}
}
/** {@inheritDoc} */
protected void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
TilesContainer container = TilesAccess.getContainer(
getServletContext(), containerKey);
mutator.mutate(container.getAttributeContext(req, res), req);
String definition = getDefinitionName(req);
if (LOG.isDebugEnabled()) {
LOG.info("Dispatching to tile '" + definition + "'");
}
container.render(definition, req, res);
}
/**
* Returns the called definition name for the given request.
*
* @param request The request to parse.
* @return The definition name to render.
*/
protected String getDefinitionName(HttpServletRequest request) {
String path = (String) request.getAttribute("javax.servlet.include.servlet_path");
if (path == null) {
path = request.getServletPath();
}
int start = path.startsWith("/") ? 1 : 0;
int end = path.endsWith(".tiles") ? path.indexOf(".tiles") : path.length();
return path.substring(start, end);
}
/** {@inheritDoc} */
protected void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
LOG.info("Tiles dispatch request received. Redirecting POST to GET.");
doGet(req, res);
}
/**
* Default no-op mutator.
*/
class DefaultMutator implements AttributeContextMutator {
/** {@inheritDoc} */
public void mutate(AttributeContext context, ServletRequest request) {
// noop;
}
}
}