RedirectViewHDIV.java

/**
 * Copyright 2005-2010 hdiv.org
 *
 * 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.hdiv.web.servlet.view;

import java.io.IOException;

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

import org.hdiv.config.HDIVConfig;
import org.hdiv.util.HDIVRequestUtils;
import org.hdiv.util.HDIVUtil;
import org.springframework.http.HttpStatus;
import org.springframework.web.servlet.view.RedirectView;

/**
 * <p>View that redirects to an absolute, context relative, or current request
 * relative URL. By default all primitive model attributes (or collections
 * thereof) are exposed as HTTP query parameters, but this behavior can be changed
 * by overriding the {@link #isEligibleProperty(String, Object)} method.
 * 
 * <p>A URL for this view is supposed to be a HTTP redirect URL, i.e.
 * suitable for HttpServletResponse's <code>sendRedirect</code> method, which
 * is what actually does the redirect if the HTTP 1.0 flag is on, or via sending
 * back an HTTP 303 code - if the HTTP 1.0 compatibility flag is off.
 *
 * <p>Note that while the default value for the "contextRelative" flag is off,
 * you will probably want to almost always set it to true. With the flag off,
 * URLs starting with "/" are considered relative to the web server root, while
 * with the flag on, they are considered relative to the web application root.
 * Since most web applications will never know or care what their context path
 * actually is, they are much better off setting this flag to true, and submitting
 * paths which are to be considered relative to the web application root.
 *
 * <p><b>NOTE when using this redirect view in a Portlet environment:</b> Make sure
 * that your controller respects the Portlet <code>sendRedirect</code> constraints.
 * When e.g. using {@link org.springframework.web.portlet.mvc.SimpleFormController},
 * make sure to set your controller's
 * {@link org.springframework.web.portlet.mvc.AbstractFormController#setRedirectAction "redirectAction"}
 * property to "true", in order to make the controller base class behave accordingly.
 * 
 * @author Gorka Vicente
 * @since HDIV 2.0.6
 * @see #setHttp10Compatible
 * @see javax.servlet.http.HttpServletResponse#sendRedirect
 */
public class RedirectViewHDIV extends RedirectView {

	private HttpStatus statusCode;
	
	/**
	 * Constructor for use as a bean.
	 */
	public RedirectViewHDIV() {
		super();
	}

	/**
	 * Create a new RedirectView with the given URL.
	 * <p>
	 * The given URL will be considered as relative to the web server, not as
	 * relative to the current ServletContext.
	 * 
	 * @param url the URL to redirect to
	 * @see #RedirectView(String, boolean)
	 */
	public RedirectViewHDIV(String url) {
		super(url);
	}

	/**
	 * Create a new RedirectView with the given URL.
	 * 
	 * @param url the URL to redirect to
	 * @param contextRelative whether to interpret the given URL as relative to
	 *            the current ServletContext
	 */
	public RedirectViewHDIV(String url, boolean contextRelative) {
		super(url, contextRelative);
	}

	/**
	 * Create a new RedirectView with the given URL.
	 * 
	 * @param url the URL to redirect to
	 * @param contextRelative whether to interpret the given URL as relative to
	 *            the current ServletContext
	 * @param http10Compatible whether to stay compatible with HTTP 1.0 clients
	 */
	public RedirectViewHDIV(String url, boolean contextRelative, boolean http10Compatible) {

		super(url, contextRelative, http10Compatible);
	}

	/**
	 * Send a redirect back to the HTTP client and adds HDIV state as a
	 * parameter if <code>targetUrl</code> references our application.
	 * 
	 * @param request current HTTP request (allows for reacting to request
	 *            method)
	 * @param response current HTTP response (for sending response headers)
	 * @param targetUrl the target URL to redirect to
	 * @param http10Compatible whether to stay compatible with HTTP 1.0 clients
	 * @throws IOException if thrown by response methods
	 */
	@Override
	protected void sendRedirect(HttpServletRequest request, HttpServletResponse response, String targetUrl,
			boolean http10Compatible) throws IOException {

		if (request.getSession(false) != null) {
			
			ServletContext servletContext = request.getSession().getServletContext();
			HDIVConfig hdivConfig = HDIVUtil.getHDIVConfig(servletContext);
				
			if (HDIVRequestUtils.hasActionOrServletExtension(targetUrl, hdivConfig.getProtectedURLPatterns())) {
				targetUrl = HDIVRequestUtils.addHDIVParameterIfNecessary(request, targetUrl, hdivConfig.isValidationInUrlsWithoutParamsActivated());
			}
		}

		if (http10Compatible) {
			// Always send status code 302.
			response.sendRedirect(response.encodeRedirectURL(targetUrl));
		} else {
			HttpStatus statusCode = getHttp11StatusCode(request, response, targetUrl);
			response.setStatus(statusCode.value());
			response.setHeader("Location", response.encodeRedirectURL(targetUrl));
		}
	}
	
	/**
	 * Determines the status code to use for HTTP 1.1 compatible requests.
	 * <p>The default implemenetation returns the {@link #setStatusCode(HttpStatus) statusCode}
	 * property if set, or the value of the {@link #RESPONSE_STATUS_ATTRIBUTE} attribute. If neither are
	 * set, it defaults to {@link HttpStatus#SEE_OTHER} (303).
	 * @param request the request to inspect
	 * @return the response
	 */
	/* the "this.statusCode != null" is now in spring, so this is identical and not needed
	@Override
	protected HttpStatus getHttp11StatusCode(HttpServletRequest request, HttpServletResponse response, String targetUrl) {
		
		//TODO: testear habi�ndole asignado valor a statusCode mediante el applicationContext.xml
		if (this.statusCode != null) {
			return statusCode;
		}
		HttpStatus attributeStatusCode = (HttpStatus) request.getAttribute(View.RESPONSE_STATUS_ATTRIBUTE);
		if (attributeStatusCode != null) {
			return attributeStatusCode;
		}
		return HttpStatus.SEE_OTHER;
	}
	*/
	/**
	 * Set the status code for this view.
	 * <p>Default is to send 302/303, depending on the value of the
	 * {@link #setHttp10Compatible(boolean) http10Compatible} flag.
	 */
	public void setStatusCode(HttpStatus statusCode) {
		this.statusCode = statusCode;
	}

}