1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with 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, 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 * @apiviz.landmark
23 */
24 public interface ChunkedInput {
25
26 /**
27 * Returns {@code true} if and only if there is any data left in the
28 * stream. Please note that {@code false} does not necessarily mean that
29 * the stream has reached at its end. In a slow stream, the next chunk
30 * might be unavailable just momentarily.
31 */
32 boolean hasNextChunk() throws Exception;
33
34 /**
35 * Fetches a chunked data from the stream. The returned chunk is usually
36 * a {@link ChannelBuffer}, but you could extend an existing implementation
37 * to convert the {@link ChannelBuffer} into a different type that your
38 * handler or encoder understands. Once this method returns the last chunk
39 * and thus the stream has reached at its end, any subsequent {@link #isEndOfInput()}
40 * call must return {@code false}.
41 *
42 * @return the fetched chunk, which is usually {@link ChannelBuffer}.
43 * {@code null} if there is no data left in the stream.
44 * Please note that {@code null} does not necessarily mean that the
45 * stream has reached at its end. In a slow stream, the next chunk
46 * might be unavailable just momentarily.
47 */
48 Object nextChunk() throws Exception;
49
50 /**
51 * Return {@code true} if and only if there is no data left in the stream
52 * and the stream has reached at its end.
53 */
54 boolean isEndOfInput() throws Exception;
55
56 /**
57 * Releases the resources associated with the stream.
58 */
59 void close() throws Exception;
60 }