1 /*
2 * Copyright 2009 Red Hat, Inc.
3 *
4 * Red Hat 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 the
6 * 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, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.handler.stream;
17
18 import org.jboss.netty.buffer.ChannelBuffer;
19
20 /**
21 * A data stream of indefinite length which is consumed by {@link ChunkedWriteHandler}.
22 *
23 * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
24 * @author <a href="http://gleamynode.net/">Trustin Lee</a>
25 * @version $Rev: 2166 $, $Date: 2010-02-18 13:24:41 +0900 (Thu, 18 Feb 2010) $
26 *
27 * @apiviz.landmark
28 */
29 public interface ChunkedInput {
30
31 /**
32 * Returns {@code true} if and only if there is any data left in the
33 * stream. Please note that {@code false} does not necessarily mean that
34 * the stream has reached at its end. In a slow stream, the next chunk
35 * might be unavailable just momentarily.
36 */
37 boolean hasNextChunk() throws Exception;
38
39 /**
40 * Fetches a chunked data from the stream. The returned chunk is usually
41 * a {@link ChannelBuffer}, but you could extend an existing implementation
42 * to convert the {@link ChannelBuffer} into a different type that your
43 * handler or encoder understands. Once this method returns the last chunk
44 * and thus the stream has reached at its end, any subsequent {@link #isEndOfInput()}
45 * call must return {@code false}.
46 *
47 * @return the fetched chunk, which is usually {@link ChannelBuffer}.
48 * {@code null} if there is no data left in the stream.
49 * Please note that {@code null} does not necessarily mean that the
50 * stream has reached at its end. In a slow stream, the next chunk
51 * might be unavailable just momentarily.
52 */
53 Object nextChunk() throws Exception;
54
55 /**
56 * Return {@code true} if and only if there is no data left in the stream
57 * and the stream has reached at its end.
58 */
59 boolean isEndOfInput() throws Exception;
60
61 /**
62 * Releases the resources associated with the stream.
63 */
64 void close() throws Exception;
65 }