Transport.java revision c3f6f16bd4a2338e88275641b9f2f56e816ca377 
1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * 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 libcore.net.http;
18
19import java.io.IOException;
20import java.io.InputStream;
21import java.io.OutputStream;
22import java.net.CacheRequest;
23
24interface Transport {
25    /**
26     * Returns an output stream where the request body can be written. The
27     * returned stream will of one of two types:
28     * <ul>
29     *     <li><strong>Direct.</strong> Bytes are written to the socket and
30     *     forgotten. This is most efficient, particularly for large request
31     *     bodies. The returned stream may be buffered; the caller must call
32     *     {@link #flushRequest} before reading the response.</li>
33     *     <li><strong>Buffered.</strong> Bytes are written to an in memory
34     *     buffer, and must be explicitly flushed with a call to {@link
35     *     #writeRequestBody}. This allows HTTP authorization (401, 407)
36     *     responses to be retransmitted transparently.</li>
37     * </ul>
38     */
39    // TODO: don't bother retransmitting the request body? It's quite a corner
40    // case and there's uncertainty whether Firefox or Chrome do this
41    OutputStream createRequestBody() throws IOException;
42
43    /**
44     * This should update the HTTP engine's sentRequestMillis field.
45     */
46    void writeRequestHeaders() throws IOException;
47
48    /**
49     * Sends the request body returned by {@link #createRequestBody} to the
50     * remote peer.
51     */
52    void writeRequestBody(RetryableOutputStream requestBody) throws IOException;
53
54    /**
55     * Flush the request body to the underlying socket.
56     */
57    void flushRequest() throws IOException;
58
59    /**
60     * Read response headers and update the cookie manager.
61     */
62    ResponseHeaders readResponseHeaders() throws IOException;
63
64    // TODO: make this the content stream?
65    InputStream getTransferStream(CacheRequest cacheRequest) throws IOException;
66
67    /**
68     * Returns true if the underlying connection can be recycled.
69     */
70    boolean makeReusable(OutputStream requestBodyOut, InputStream responseBodyIn);
71}
72