/* 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.riotfamily.common.web.mvc.servlet;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.riotfamily.common.web.support.ServletUtils;
import org.springframework.web.servlet.DispatcherServlet;

/**
 * In case of a HEAD request, includes and forwards are dispatched by 
 * {@link #doGet(HttpServletRequest, HttpServletResponse)}, to make sure
 * that the calculated content-length is correct.
 */
public class HeadDispatcherServlet extends DispatcherServlet {
	
	/**
	 * Overrides the default implementation to invoke doGet() instead of 
	 * doHead() if the request is included or forwarded by a RequestDispatcher. 
	 */
	@Override
	protected void doHead(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		if (ServletUtils.isDirectRequest(request)) {
			super.doHead(request, response);
		}
		else {
			doGet(request, response);
		}
	}

}