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1   //========================================================================
2   //Copyright 2004-2008 Mort Bay Consulting Pty. Ltd.
3   //------------------------------------------------------------------------
4   //Licensed under the Apache License, Version 2.0 (the "License");
5   //you may not use this file except in compliance with the License.
6   //You may obtain a copy of the License at 
7   //http://www.apache.org/licenses/LICENSE-2.0
8   //Unless required by applicable law or agreed to in writing, software
9   //distributed under the License is distributed on an "AS IS" BASIS,
10  //WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11  //See the License for the specific language governing permissions and
12  //limitations under the License.
13  //========================================================================
14  
15  package org.mortbay.servlet.jetty;
16  
17  import java.io.IOException;
18  import java.io.OutputStream;
19  import java.io.OutputStreamWriter;
20  import java.io.PrintWriter;
21  import java.io.UnsupportedEncodingException;
22  
23  import javax.servlet.FilterConfig;
24  import javax.servlet.ServletException;
25  import javax.servlet.http.HttpServletRequest;
26  import javax.servlet.http.HttpServletResponse;
27  
28  import org.mortbay.io.UncheckedPrintWriter;
29  import org.mortbay.jetty.HttpConnection;
30  import org.mortbay.servlet.GzipFilter;
31  
32  /* ------------------------------------------------------------ */
33  /** Includable GZip Filter.
34   * This extension to the {@link GzipFilter} that uses Jetty APIs to allow
35   * headers to be set during calls to 
36   * {@link javax.servlet.RequestDispatcher#include(javax.servlet.ServletRequest, javax.servlet.ServletResponse)}.
37   * This allows the gzip filter to function correct during includes and to make a decision to gzip or not
38   * at the time the buffer fills and on the basis of all response headers.
39   * 
40   * If the init parameter "uncheckedPrintWriter" is set to "true", then the PrintWriter used by
41   * the wrapped getWriter will be {@link UncheckedPrintWriter}.
42   *
43   */
44  public class IncludableGzipFilter extends GzipFilter
45  {
46      boolean _uncheckedPrintWriter=false;
47      
48      public void init(FilterConfig filterConfig) throws ServletException
49      {
50          super.init(filterConfig);
51          
52          String tmp=filterConfig.getInitParameter("uncheckedPrintWriter");
53          if (tmp!=null)
54              _uncheckedPrintWriter=Boolean.valueOf(tmp).booleanValue();
55      }
56      
57      protected GZIPResponseWrapper newGZIPResponseWrapper(HttpServletRequest request, HttpServletResponse response)
58      {
59          return new IncludableResponseWrapper(request,response);
60      }
61  
62      public class IncludableResponseWrapper extends GzipFilter.GZIPResponseWrapper
63      {
64          public IncludableResponseWrapper(HttpServletRequest request, HttpServletResponse response)
65          {
66              super(request,response);
67          }
68          
69          protected GzipStream newGzipStream(HttpServletRequest request,HttpServletResponse response,long contentLength,int bufferSize, int minGzipSize) throws IOException
70          {
71              return new IncludableGzipStream(request,response,contentLength,bufferSize,minGzipSize);
72          }
73      }
74      
75      public class IncludableGzipStream extends GzipFilter.GzipStream
76      {
77          public IncludableGzipStream(HttpServletRequest request, HttpServletResponse response, long contentLength, int bufferSize, int minGzipSize)
78                  throws IOException
79          {
80              super(request,response,contentLength,bufferSize,minGzipSize);
81          }
82  
83          protected boolean setContentEncodingGzip()
84          {
85              HttpConnection connection = HttpConnection.getCurrentConnection();
86              connection.getResponseFields().put("Content-Encoding", "gzip");
87              return true;
88          }
89      }
90      
91      protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
92      {
93          if (_uncheckedPrintWriter)
94              return encoding==null?new UncheckedPrintWriter(out):new UncheckedPrintWriter(new OutputStreamWriter(out,encoding));
95          return super.newWriter(out,encoding);
96      }
97  }