Source code: org/apache/http/protocol/RequestUserAgent.java
1 /*
2 * $HeadURL: https://svn.apache.org/repos/asf/jakarta/httpcomponents/httpcore/tags/4.0-alpha2/src/java/org/apache/http/protocol/RequestUserAgent.java $
3 * $Revision: 408172 $
4 * $Date: 2006-05-21 16:06:29 +0200 (Sun, 21 May 2006) $
5 *
6 * ====================================================================
7 *
8 * Copyright 1999-2006 The Apache Software Foundation
9 *
10 * Licensed under the Apache License, Version 2.0 (the "License");
11 * you may not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
16 * Unless required by applicable law or agreed to in writing, software
17 * distributed under the License is distributed on an "AS IS" BASIS,
18 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 * See the License for the specific language governing permissions and
20 * limitations under the License.
21 * ====================================================================
22 *
23 * This software consists of voluntary contributions made by many
24 * individuals on behalf of the Apache Software Foundation. For more
25 * information on the Apache Software Foundation, please see
26 * <http://www.apache.org/>.
27 *
28 */
29
30 package org.apache.http.protocol;
31
32 import java.io.IOException;
33
34 import org.apache.http.HttpException;
35 import org.apache.http.HttpRequest;
36 import org.apache.http.HttpRequestInterceptor;
37 import org.apache.http.params.HttpProtocolParams;
38
39 /**
40 * A request interceptor that adds a User-Agent header.
41 *
42 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
43 *
44 * @version $Revision: 408172 $
45 *
46 * @since 4.0
47 */
48 public class RequestUserAgent implements HttpRequestInterceptor {
49
50 public RequestUserAgent() {
51 super();
52 }
53
54 public void process(final HttpRequest request, final HttpContext context)
55 throws HttpException, IOException {
56 if (request == null) {
57 throw new IllegalArgumentException("HTTP request may not be null");
58 }
59 if (!request.containsHeader(HTTP.USER_AGENT)) {
60 String useragent = HttpProtocolParams.getUserAgent(request.getParams());
61 if (useragent != null) {
62 request.addHeader(new GeneratedHeader(HTTP.USER_AGENT, useragent));
63 }
64 }
65 }
66
67 }