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
28 package org.apache.http.nio.util;
29
30 import java.io.IOException;
31
32 import org.apache.http.nio.ContentDecoder;
33
34 /**
35 * Buffer for storing content streamed out from a {@link ContentDecoder}.
36 *
37 * @since 4.0
38 */
39 public interface ContentInputBuffer {
40
41 /**
42 * Reads content from the given {@link ContentDecoder} and stores it in
43 * this buffer.
44 *
45 * @param decoder the content decoder.
46 * @return number of bytes read.
47 * @throws IOException in case of an I/O error.
48 */
49 int consumeContent(ContentDecoder decoder) throws IOException;
50
51 /**
52 * Resets the buffer by clearing its state and stored content.
53 */
54 void reset();
55
56 /**
57 * Reads up to <code>len</code> bytes of data from this buffer into
58 * an array of bytes. The exact number of bytes read depends how many bytes
59 * are stored in the buffer.
60 *
61 * <p> If <code>off</code> is negative, or <code>len</code> is negative, or
62 * <code>off+len</code> is greater than the length of the array
63 * <code>b</code>, this method can throw a runtime exception. The exact type
64 * of runtime exception thrown by this method depends on implementation.
65 * This method returns <code>-1</code> if the end of content stream has been
66 * reached.
67 *
68 * @param b the buffer into which the data is read.
69 * @param off the start offset in array <code>b</code>
70 * at which the data is written.
71 * @param len the maximum number of bytes to read.
72 * @return the total number of bytes read into the buffer, or
73 * <code>-1</code> if there is no more data because the end of
74 * the stream has been reached.
75 * @exception IOException if an I/O error occurs.
76 */
77 int read(byte[] b, int off, int len) throws IOException;
78
79 /**
80 * Reads one byte from this buffer. If the buffer is empty this method can
81 * throw a runtime exception. The exact type of runtime exception thrown
82 * by this method depends on implementation. This method returns
83 * <code>-1</code> if the end of content stream has been reached.
84 *
85 * @return one byte
86 */
87 int read() throws IOException;
88
89 }