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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  
18  import javax.servlet.Filter;
19  import javax.servlet.FilterChain;
20  import javax.servlet.FilterConfig;
21  import javax.servlet.ServletContext;
22  import javax.servlet.ServletException;
23  import javax.servlet.ServletRequest;
24  import javax.servlet.ServletRequestWrapper;
25  import javax.servlet.ServletResponse;
26  import javax.servlet.http.HttpServletRequest;
27  import javax.servlet.http.HttpServletRequestWrapper;
28  
29  /* ------------------------------------------------------------ */
30  /** TestFilter.
31   * 
32   *
33   */
34  public class TestFilter implements Filter
35  {
36      private ServletContext _context;
37      
38      /* ------------------------------------------------------------ */
39      /* 
40       * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
41       */
42      public void init(FilterConfig filterConfig) throws ServletException
43      {
44          _context= filterConfig.getServletContext();
45      }
46  
47      /* ------------------------------------------------------------ */
48      /* 
49       * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
50       */
51      public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
52              throws IOException, ServletException
53      {
54          Integer old_value=null;
55          ServletRequest r = request;
56          while (r instanceof ServletRequestWrapper)
57              r=((ServletRequestWrapper)r).getRequest();
58          
59          try
60          {
61              old_value=(Integer)request.getAttribute("testFilter");
62              
63              Integer value=(old_value==null)?new Integer(1):new Integer(old_value.intValue()+1);
64                          
65              request.setAttribute("testFilter", value);
66              
67              String qString = ((HttpServletRequest)request).getQueryString();
68              if (qString != null && qString.indexOf("wrap")>=0)
69              {
70                  request=new HttpServletRequestWrapper((HttpServletRequest)request);
71              }
72              _context.setAttribute("request"+r.hashCode(),value);
73              
74              chain.doFilter(request, response);
75          }
76          finally
77          {
78              request.setAttribute("testFilter", old_value);
79              _context.setAttribute("request"+r.hashCode(),old_value);
80          }
81      }
82  
83      /* ------------------------------------------------------------ */
84      /* 
85       * @see javax.servlet.Filter#destroy()
86       */
87      public void destroy()
88      {
89      }
90  
91  }