1/*
2 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/protocol/RequestTargetHost.java $
3 * $Revision: 573864 $
4 * $Date: 2007-09-08 08:53:25 -0700 (Sat, 08 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;
35import java.net.InetAddress;
36
37import org.apache.http.HttpConnection;
38import org.apache.http.HttpException;
39import org.apache.http.HttpHost;
40import org.apache.http.HttpInetConnection;
41import org.apache.http.HttpRequest;
42import org.apache.http.HttpRequestInterceptor;
43import org.apache.http.HttpVersion;
44import org.apache.http.ProtocolVersion;
45import org.apache.http.ProtocolException;
46
47/**
48 * A request interceptor that sets the Host header for HTTP/1.1 requests.
49 *
50 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
51 *
52 * @version $Revision: 573864 $
53 *
54 * @since 4.0
55 */
56public class RequestTargetHost implements HttpRequestInterceptor {
57
58    public RequestTargetHost() {
59        super();
60    }
61
62    public void process(final HttpRequest request, final HttpContext context)
63            throws HttpException, IOException {
64        if (request == null) {
65            throw new IllegalArgumentException("HTTP request may not be null");
66        }
67        if (context == null) {
68            throw new IllegalArgumentException("HTTP context may not be null");
69        }
70        if (!request.containsHeader(HTTP.TARGET_HOST)) {
71            HttpHost targethost = (HttpHost) context
72                .getAttribute(ExecutionContext.HTTP_TARGET_HOST);
73            if (targethost == null) {
74                HttpConnection conn = (HttpConnection) context
75                    .getAttribute(ExecutionContext.HTTP_CONNECTION);
76                if (conn instanceof HttpInetConnection) {
77                    // Populate the context with a default HTTP host based on the
78                    // inet address of the target host
79                    InetAddress address = ((HttpInetConnection) conn).getRemoteAddress();
80                    int port = ((HttpInetConnection) conn).getRemotePort();
81                    if (address != null) {
82                        targethost = new HttpHost(address.getHostName(), port);
83                    }
84                }
85                if (targethost == null) {
86                    ProtocolVersion ver = request.getRequestLine().getProtocolVersion();
87                    if (ver.lessEquals(HttpVersion.HTTP_1_0)) {
88                        return;
89                    } else {
90                        throw new ProtocolException("Target host missing");
91                    }
92                }
93            }
94            request.addHeader(HTTP.TARGET_HOST, targethost.toHostString());
95        }
96    }
97
98}
99