ResponseServer.java revision 417f3b92ba4549b2f22340e3107d869d2b9c5bb8 
1/*
2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/protocol/ResponseServer.java $
3 * $Revision: 576073 $
4 * $Date: 2007-09-16 03:53:13 -0700 (Sun, 16 Sep 2007) $
5 *
6 * ====================================================================
7 * Licensed to the Apache Software Foundation (ASF) under one
8 * or more contributor license agreements.  See the NOTICE file
9 * distributed with this work for additional information
10 * regarding copyright ownership.  The ASF licenses this file
11 * to you under the Apache License, Version 2.0 (the
12 * "License"); you may not use this file except in compliance
13 * with the License.  You may obtain a copy of the License at
14 *
15 *   http://www.apache.org/licenses/LICENSE-2.0
16 *
17 * Unless required by applicable law or agreed to in writing,
18 * software distributed under the License is distributed on an
19 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
20 * KIND, either express or implied.  See the License for the
21 * specific language governing permissions and limitations
22 * under the License.
23 * ====================================================================
24 *
25 * This software consists of voluntary contributions made by many
26 * individuals on behalf of the Apache Software Foundation.  For more
27 * information on the Apache Software Foundation, please see
28 * <http://www.apache.org/>.
29 *
30 */
31
32package org.apache.http.protocol;
33
34import java.io.IOException;
35
36import org.apache.http.HttpException;
37import org.apache.http.HttpResponse;
38import org.apache.http.HttpResponseInterceptor;
39import org.apache.http.params.CoreProtocolPNames;
40
41/**
42 * A response interceptor that adds a Server header.
43 * For use on the server side.
44 *
45 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
46 *
47 * @version $Revision: 576073 $
48 *
49 * @since 4.0
50 */
51public class ResponseServer implements HttpResponseInterceptor {
52
53    public ResponseServer() {
54        super();
55    }
56
57    public void process(final HttpResponse response, final HttpContext context)
58            throws HttpException, IOException {
59        if (response == null) {
60            throw new IllegalArgumentException("HTTP request may not be null");
61        }
62        if (!response.containsHeader(HTTP.SERVER_HEADER)) {
63            String s = (String) response.getParams().getParameter(
64                    CoreProtocolPNames.ORIGIN_SERVER);
65            if (s != null) {
66                response.addHeader(HTTP.SERVER_HEADER, s);
67            }
68        }
69    }
70
71}
72