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 package org.apache.http.client.protocol;
28
29 import java.io.IOException;
30
31 import org.apache.http.HttpException;
32 import org.apache.http.HttpRequest;
33 import org.apache.http.HttpRequestInterceptor;
34 import org.apache.http.annotation.Immutable;
35 import org.apache.http.protocol.HttpContext;
36
37 /**
38 * Class responsible for handling Content Encoding requests in HTTP.
39 * <p>
40 * Instances of this class are stateless, therefore they're thread-safe and immutable.
41 *
42 * @see "http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.5"
43 *
44 * @since 4.1
45 */
46 @Immutable
47 public class RequestAcceptEncoding implements HttpRequestInterceptor {
48
49 /**
50 * Adds the header {@code "Accept-Encoding: gzip,deflate"} to the request.
51 */
52 public void process(
53 final HttpRequest request,
54 final HttpContext context) throws HttpException, IOException {
55
56 /* Signal support for Accept-Encoding transfer encodings. */
57 if (!request.containsHeader("Accept-Encoding")) {
58 request.addHeader("Accept-Encoding", "gzip,deflate");
59 }
60 }
61
62 }