View Javadoc

1   //
2   //  ========================================================================
3   //  Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
4   //  ------------------------------------------------------------------------
5   //  All rights reserved. This program and the accompanying materials
6   //  are made available under the terms of the Eclipse Public License v1.0
7   //  and Apache License v2.0 which accompanies this distribution.
8   //
9   //      The Eclipse Public License is available at
10  //      http://www.eclipse.org/legal/epl-v10.html
11  //
12  //      The Apache License v2.0 is available at
13  //      http://www.opensource.org/licenses/apache2.0.php
14  //
15  //  You may elect to redistribute this code under either of these licenses.
16  //  ========================================================================
17  //
18  
19  package org.eclipse.jetty.servlets;
20  import java.io.IOException;
21  
22  import javax.servlet.Filter;
23  import javax.servlet.FilterChain;
24  import javax.servlet.FilterConfig;
25  import javax.servlet.ServletException;
26  import javax.servlet.ServletRequest;
27  import javax.servlet.ServletResponse;
28  import javax.servlet.http.HttpServletRequest;
29  
30  /* ------------------------------------------------------------ */
31  /** Welcome Filter
32   * This filter can be used to server an index file for a directory 
33   * when no index file actually exists (thus the web.xml mechanism does
34   * not work).
35   * 
36   * This filter will dispatch requests to a directory (URLs ending with /)
37   * to the welcome URL determined by the "welcome" init parameter.  So if
38   * the filter "welcome" init parameter is set to "index.do" then a request
39   * to "/some/directory/" will be dispatched to "/some/directory/index.do" and
40   * will be handled by any servlets mapped to that URL.
41   *
42   * Requests to "/some/directory" will be redirected to "/some/directory/".
43   */
44  public  class WelcomeFilter implements Filter
45  {
46      private String welcome;
47      
48      public void init(FilterConfig filterConfig)
49      {
50          welcome=filterConfig.getInitParameter("welcome");
51  	if (welcome==null)
52  	    welcome="index.html";
53      }
54  
55      /* ------------------------------------------------------------ */
56      public void doFilter(ServletRequest request,
57                           ServletResponse response,
58                           FilterChain chain)
59  	throws IOException, ServletException
60      {
61          String path=((HttpServletRequest)request).getServletPath();
62          if (welcome!=null && path.endsWith("/"))
63              request.getRequestDispatcher(path+welcome).forward(request,response);
64          else
65              chain.doFilter(request, response);
66      }
67  
68      public void destroy() {}
69  }
70