1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.protocol;
29
30 import java.io.IOException;
31
32 import org.apache.http.HttpException;
33 import org.apache.http.HttpResponse;
34 import org.apache.http.HttpResponseInterceptor;
35 import org.apache.http.annotation.ThreadingBehavior;
36 import org.apache.http.annotation.Contract;
37 import org.apache.http.util.Args;
38
39 /**
40 * ResponseServer is responsible for adding {@code Server} header. This
41 * interceptor is recommended for server side protocol processors.
42 *
43 * @since 4.0
44 */
45 @Contract(threading = ThreadingBehavior.IMMUTABLE)
46 public class ResponseServer implements HttpResponseInterceptor {
47
48 private final String originServer;
49
50 /**
51 * @since 4.3
52 */
53 public ResponseServer(final String originServer) {
54 super();
55 this.originServer = originServer;
56 }
57
58 public ResponseServer() {
59 this(null);
60 }
61
62 @Override
63 public void process(final HttpResponse response, final HttpContext context)
64 throws HttpException, IOException {
65 Args.notNull(response, "HTTP response");
66 if (!response.containsHeader(HTTP.SERVER_HEADER)) {
67 if (this.originServer != null) {
68 response.addHeader(HTTP.SERVER_HEADER, this.originServer);
69 }
70 }
71 }
72
73 }