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1   /**
2    * Logback: the reliable, generic, fast and flexible logging framework.
3    * Copyright (C) 1999-2009, QOS.ch. All rights reserved.
4    *
5    * This program and the accompanying materials are dual-licensed under
6    * either the terms of the Eclipse Public License v1.0 as published by
7    * the Eclipse Foundation
8    *
9    *   or (per the licensee's choosing)
10   *
11   * under the terms of the GNU Lesser General Public License version 2.1
12   * as published by the Free Software Foundation.
13   */
14  package ch.qos.logback.access.servlet;
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.ServletException;
22  import javax.servlet.ServletRequest;
23  import javax.servlet.ServletResponse;
24  import javax.servlet.http.HttpServletRequest;
25  import javax.servlet.http.HttpServletResponse;
26  
27  import ch.qos.logback.access.AccessConstants;
28  
29  public class TeeFilter implements Filter {
30  
31    public void destroy() {
32      // NOP
33    }
34  
35    public void doFilter(ServletRequest request, ServletResponse response,
36        FilterChain filterChain) throws IOException, ServletException {
37  
38      if (request instanceof HttpServletRequest) {
39        try {
40          TeeHttpServletRequest teeRequest = new TeeHttpServletRequest(
41              (HttpServletRequest) request);
42          TeeHttpServletResponse teeResponse = new TeeHttpServletResponse(
43              (HttpServletResponse) response);
44          
45          //System.out.println("BEFORE TeeFilter. filterChain.doFilter()");
46          filterChain.doFilter(teeRequest, teeResponse);
47          //System.out.println("AFTER TeeFilter. filterChain.doFilter()");
48  
49          teeResponse.finish();
50          // let the output contents be available for later use by
51          // logback-access-logging
52          teeRequest.setAttribute(AccessConstants.LB_OUTPUT_BUFFER, teeResponse
53              .getOutputBuffer());
54        } catch (IOException e) {
55          e.printStackTrace();
56          throw e;
57        } catch (ServletException e) {
58          e.printStackTrace();
59          throw e;
60        }
61      } else {
62        filterChain.doFilter(request, response);
63      }
64  
65    }
66  
67    public void init(FilterConfig arg0) throws ServletException {
68      // NOP
69    }
70  
71  }