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1   // ========================================================================
2   // Copyright (c) 2004-2009 Mort Bay Consulting Pty. Ltd.
3   // ------------------------------------------------------------------------
4   // All rights reserved. This program and the accompanying materials
5   // are made available under the terms of the Eclipse Public License v1.0
6   // and Apache License v2.0 which accompanies this distribution.
7   // The Eclipse Public License is available at 
8   // http://www.eclipse.org/legal/epl-v10.html
9   // The Apache License v2.0 is available at
10  // http://www.opensource.org/licenses/apache2.0.php
11  // You may elect to redistribute this code under either of these licenses. 
12  // ========================================================================
13  
14  package com.acme;
15  
16  import java.io.IOException;
17  import java.util.HashSet;
18  import java.util.Set;
19  
20  import javax.servlet.Filter;
21  import javax.servlet.FilterChain;
22  import javax.servlet.FilterConfig;
23  import javax.servlet.ServletContext;
24  import javax.servlet.ServletException;
25  import javax.servlet.ServletRequest;
26  import javax.servlet.ServletRequestWrapper;
27  import javax.servlet.ServletResponse;
28  import javax.servlet.http.HttpServletRequest;
29  import javax.servlet.http.HttpServletRequestWrapper;
30  import javax.servlet.http.HttpServletResponse;
31  
32  /* ------------------------------------------------------------ */
33  /** TestFilter.
34   * 
35   * This filter checks for a none local request, and if the init parameter
36   * "remote" is not set to true, then all non local requests are forwarded
37   * to /remote.html
38   * 
39   */
40  public class TestFilter implements Filter
41  {
42      private boolean _remote;
43      private ServletContext _context;
44      private final Set<String> _allowed = new HashSet<String>();
45      
46      /* ------------------------------------------------------------ */
47      /* 
48       * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
49       */
50      public void init(FilterConfig filterConfig) throws ServletException
51      {
52          _context= filterConfig.getServletContext();
53          _remote=Boolean.parseBoolean(_context.getInitParameter("remote"));
54          _allowed.add("/favicon.ico");
55          _allowed.add("/jetty_banner.gif");
56          _allowed.add("/remote.html");
57      }
58  
59      /* ------------------------------------------------------------ */
60      /* 
61       * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
62       */
63      public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
64              throws IOException, ServletException
65      {
66          String from = request.getRemoteHost();
67          String to = request.getServerName();
68          
69          if ((!_remote&&!from.equals("localhost")&&!from.startsWith("127.0.0.")||
70               !to.equals("localhost")&&!to.startsWith("127.0.0.")) &&
71               !_allowed.contains(((HttpServletRequest)request).getServletPath()))
72          {
73              ((HttpServletResponse)response).sendRedirect("/remote.html");
74              return;
75          }
76          
77          Integer old_value=null;
78          ServletRequest r = request;
79          while (r instanceof ServletRequestWrapper)
80              r=((ServletRequestWrapper)r).getRequest();
81          
82          try
83          {
84              old_value=(Integer)request.getAttribute("testFilter");
85              
86              Integer value=(old_value==null)?new Integer(1):new Integer(old_value.intValue()+1);
87                          
88              request.setAttribute("testFilter", value);
89              
90              String qString = ((HttpServletRequest)request).getQueryString();
91              if (qString != null && qString.indexOf("wrap")>=0)
92              {
93                  request=new HttpServletRequestWrapper((HttpServletRequest)request);
94              }
95              _context.setAttribute("request"+r.hashCode(),value);
96              
97              chain.doFilter(request, response);
98          }
99          finally
100         {
101             request.setAttribute("testFilter", old_value);
102             _context.setAttribute("request"+r.hashCode(),old_value);
103         }
104     }
105 
106     /* ------------------------------------------------------------ */
107     /* 
108      * @see javax.servlet.Filter#destroy()
109      */
110     public void destroy()
111     {
112     }
113 
114 }