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1   /* HttpRecorderGetMethod
2    *
3    * Created on Feb 24, 2004
4    *
5    * Copyright (C) 2003 Internet Archive.
6    *
7    * This file is part of the Heritrix web crawler (crawler.archive.org).
8    *
9    * Heritrix is free software; you can redistribute it and/or modify
10   * it under the terms of the GNU Lesser Public License as published by
11   * the Free Software Foundation; either version 2.1 of the License, or
12   * any later version.
13   *
14   * Heritrix is distributed in the hope that it will be useful,
15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   * GNU Lesser Public License for more details.
18   *
19   * You should have received a copy of the GNU Lesser Public License
20   * along with Heritrix; if not, write to the Free Software
21   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22   */
23  package org.archive.httpclient;
24  
25  import java.io.IOException;
26  import java.util.logging.Logger;
27  
28  import org.apache.commons.httpclient.HttpConnection;
29  import org.apache.commons.httpclient.HttpException;
30  import org.apache.commons.httpclient.HttpState;
31  import org.apache.commons.httpclient.methods.GetMethod;
32  import org.archive.util.HttpRecorder;
33  
34  
35  /***
36   * Override of GetMethod that marks the passed HttpRecorder w/ the transition
37   * from HTTP head to body and that forces a close on the http connection.
38   *
39   * The actions done in this subclass used to be done by copying
40   * org.apache.commons.HttpMethodBase, overlaying our version in place of the
41   * one that came w/ httpclient.  Here is the patch of the difference between
42   * shipped httpclient code and our mods:
43   * <pre>
44   *    -- -1338,6 +1346,12 --
45   *
46   *        public void releaseConnection() {
47   *
48   *   +        // HERITRIX always ants the streams closed.
49   *   +        if (responseConnection != null)
50   *   +        {
51   *   +            responseConnection.close();
52   *   +        }
53   *   +
54   *            if (responseStream != null) {
55   *                try {
56   *                    // FYI - this may indirectly invoke responseBodyConsumed.
57   *   -- -1959,6 +1973,11 --
58   *                        this.statusLine = null;
59   *                    }
60   *                }
61   *   +            // HERITRIX mark transition from header to content.
62   *   +            if (this.httpRecorder != null)
63   *   +            {
64   *   +                this.httpRecorder.markContentBegin();
65   *   +            }
66   *                readResponseBody(state, conn);
67   *                processResponseBody(state, conn);
68   *            } catch (IOException e) {
69   * </pre>
70   * 
71   * <p>We're not supposed to have access to the underlying connection object;
72   * am only violating contract because see cases where httpclient is skipping
73   * out w/o cleaning up after itself.
74   *
75   * @author stack
76   * @version $Revision: 4646 $, $Date: 2006-09-22 17:23:04 +0000 (Fri, 22 Sep 2006) $
77   */
78  public class HttpRecorderGetMethod extends GetMethod {
79      
80      protected static Logger logger =
81          Logger.getLogger(HttpRecorderGetMethod.class.getName());
82      
83      /***
84       * Instance of http recorder method.
85       */
86      protected HttpRecorderMethod httpRecorderMethod = null;
87      
88  
89  	public HttpRecorderGetMethod(String uri, HttpRecorder recorder) {
90  		super(uri);
91          this.httpRecorderMethod = new HttpRecorderMethod(recorder);
92  	}
93  
94  	protected void readResponseBody(HttpState state, HttpConnection connection)
95  	throws IOException, HttpException {
96          // We're about to read the body.  Mark transition in http recorder.
97  		this.httpRecorderMethod.markContentBegin(connection);
98  		super.readResponseBody(state, connection);
99  	}
100 
101     protected boolean shouldCloseConnection(HttpConnection conn) {
102         // Always close connection after each request. As best I can tell, this
103         // is superfluous -- we've set our client to be HTTP/1.0.  Doing this
104         // out of paranoia.
105         return true;
106     }
107 
108     public int execute(HttpState state, HttpConnection conn)
109     throws HttpException, IOException {
110         // Save off the connection so we can close it on our way out in case
111         // httpclient fails to (We're not supposed to have access to the
112         // underlying connection object; am only violating contract because
113         // see cases where httpclient is skipping out w/o cleaning up
114         // after itself).
115         this.httpRecorderMethod.setConnection(conn);
116         return super.execute(state, conn);
117     }
118     
119     protected void addProxyConnectionHeader(HttpState state, HttpConnection conn)
120             throws IOException, HttpException {
121         super.addProxyConnectionHeader(state, conn);
122         this.httpRecorderMethod.handleAddProxyConnectionHeader(this);
123     }
124 }