CacheResponse.java revision 72e93344b4d1ffc71e9c832ec23de0657e5b04a5 
1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package java.net;
18
19import java.io.IOException;
20import java.io.InputStream;
21import java.util.List;
22import java.util.Map;
23
24/**
25 * {@code CacheResponse} is used for getting resource data from the installed
26 * {@code ResponseCache}. A {@code CacheResponse} object provides an {@code
27 * InputStream} to access the response body and also a method {@code
28 * getHeaders()} to fetch the response headers.
29 *
30 * @see ResponseCache
31 */
32public abstract class CacheResponse {
33    /**
34     * This implementation does nothing.
35     */
36    public CacheResponse() {
37        super();
38    }
39
40    /**
41     * Returns an {@code InputStream} to access the response body.
42     *
43     * @return an {@code InputStream} which can be used to fetch the response
44     *         body.
45     * @throws IOException
46     *             if an I/O error is encountered while retrieving the response
47     *             body.
48     */
49    public abstract InputStream getBody() throws IOException;
50
51    /**
52     * Returns an immutable {@code Map} which contains the response headers
53     * information.
54     *
55     * @return an immutable {@code Map} which contains the response headers. The
56     *         generic map contains response header fields as the key and a list
57     *         of strings as values.
58     * @throws IOException
59     *             if an I/O error is encountered while retrieving the response
60     *             headers.
61     */
62    public abstract Map<String, List<String>> getHeaders() throws IOException;
63}
64