/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * 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.acegisecurity.adapters;

 import org.acegisecurity.Authentication;

 import org.acegisecurity.context.SecurityContextHolder;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import java.io.IOException;

 import java.security.Principal;

 import javax.servlet.Filter;

 import javax.servlet.FilterChain;

 import javax.servlet.FilterConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 import javax.servlet.http.HttpServletRequest;

 /**

  * Populates <code>SecurityContext</code> with the <code>Authentication</code> obtained from the container's

  * <code>HttpServletRequest.getUserPrincipal()</code>.<p>Use this filter with container adapters only.</p>

  *  <p>This filter <b>never</b> preserves the <code>Authentication</code> on the <code>SecurityContext</code> - it

  * is replaced every request.</p>

  *  <p>See {@link org.acegisecurity.context.HttpSessionContextIntegrationFilter} for further information.</p>

  *

  * @author Ben Alex

  * @version $Id: HttpRequestIntegrationFilter.java 1496 2006-05-23 13:38:33Z benalex $

  */

 public class HttpRequestIntegrationFilter implements Filter {

     //~ Static fields/initializers =====================================================================================

     private static final Log logger = LogFactory.getLog(HttpRequestIntegrationFilter.class);

     //~ Methods ========================================================================================================

     /**

      * Does nothing. We use IoC container lifecycle services instead.

      */

     public void destroy() {}

     public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

         throws IOException, ServletException {

         if (request instanceof HttpServletRequest) {

             Principal principal = ((HttpServletRequest) request).getUserPrincipal();

             if ((principal != null) && principal instanceof Authentication) {

                 SecurityContextHolder.getContext().setAuthentication((Authentication) principal);

                 if (logger.isDebugEnabled()) {

                     logger.debug("SecurityContextHolder updated with Authentication from container: '" + principal

                         + "'");

                 }

             } else {

                 if (logger.isDebugEnabled()) {

                     logger.debug("SecurityContextHolder not set with new Authentication as Principal was: '"

                         + principal + "'");

                 }

             }

         } else {

             throw new IllegalArgumentException("Only HttpServletRequest is acceptable");

         }

         chain.doFilter(request, response);

     }

     /**

      * Does nothing. We use IoC container lifecycle services instead.

      *

      * @param arg0 ignored

      *

      * @throws ServletException ignored

      */

     public void init(FilterConfig arg0) throws ServletException {}

 }