/*
* Copyright 2002-2016 the original author or authors.
*
* 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.springframework.security.web;
import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.security.web.util.UrlUtils;
/**
* Simple implementation of <tt>RedirectStrategy</tt> which is the default used throughout
* the framework.
*
* @author Luke Taylor
* @since 3.0
*/
public class DefaultRedirectStrategy implements RedirectStrategy {
protected final Log logger = LogFactory.getLog(getClass());
private boolean contextRelative;
/**
* Redirects the response to the supplied URL.
* <p>
* If <tt>contextRelative</tt> is set, the redirect value will be the value after the
* request context path. Note that this will result in the loss of protocol
* information (HTTP or HTTPS), so will cause problems if a redirect is being
* performed to change to HTTPS, for example.
*/
public void sendRedirect(HttpServletRequest request, HttpServletResponse response,
String url) throws IOException {
String redirectUrl = calculateRedirectUrl(request.getContextPath(), url);
redirectUrl = response.encodeRedirectURL(redirectUrl);
if (logger.isDebugEnabled()) {
logger.debug("Redirecting to '" + redirectUrl + "'");
}
response.sendRedirect(redirectUrl);
}
protected String calculateRedirectUrl(String contextPath, String url) {
if (!UrlUtils.isAbsoluteUrl(url)) {
if (isContextRelative()) {
return url;
}
else {
return contextPath + url;
}
}
// Full URL, including http(s)://
if (!isContextRelative()) {
return url;
}
// Calculate the relative URL from the fully qualified URL, minus the last
// occurrence of the scheme and base context.
url = url.substring(url.lastIndexOf("://") + 3); // strip off scheme
url = url.substring(url.indexOf(contextPath) + contextPath.length());
if (url.length() > 1 && url.charAt(0) == '/') {
url = url.substring(1);
}
return url;
}
/**
* If <tt>true</tt>, causes any redirection URLs to be calculated minus the protocol
* and context path (defaults to <tt>false</tt>).
*/
public void setContextRelative(boolean useRelativeContext) {
this.contextRelative = useRelativeContext;
}
/**
* Returns <tt>true</tt>, if the redirection URL should be calculated
* minus the protocol and context path (defaults to <tt>false</tt>).
*/
protected boolean isContextRelative() {
return contextRelative;
}
}