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.hc.core5.http.io;
29
30 import java.io.IOException;
31 import java.io.InputStream;
32
33 import org.apache.hc.core5.util.CharArrayBuffer;
34
35 /**
36 * Session input buffer for HTTP/1.1 blocking connections.
37 * <p>
38 * This interface facilitates intermediate buffering of input data streamed from
39 * an input stream and provides methods for reading lines of text.
40 *
41 * @since 4.0
42 */
43 public interface SessionInputBuffer {
44
45 /**
46 * Returns length data stored in the buffer
47 *
48 * @return data length
49 */
50 int length();
51
52 /**
53 * Returns total capacity of the buffer
54 *
55 * @return total capacity
56 */
57 int capacity();
58
59 /**
60 * Returns available space in the buffer.
61 *
62 * @return available space.
63 */
64 int available();
65
66 /**
67 * Reads up to {@code len} bytes of data from the session buffer into
68 * an array of bytes. An attempt is made to read as many as
69 * {@code len} bytes, but a smaller number may be read, possibly
70 * zero. The number of bytes actually read is returned as an integer.
71 *
72 * <p> This method blocks until input data is available, end of file is
73 * detected, or an exception is thrown.
74 *
75 * <p> If {@code off} is negative, or {@code len} is negative, or
76 * {@code off+len} is greater than the length of the array
77 * {@code b}, then an {@code IndexOutOfBoundsException} is
78 * thrown.
79 *
80 * @param b the buffer into which the data is read.
81 * @param off the start offset in array {@code b}
82 * at which the data is written.
83 * @param len the maximum number of bytes to read.
84 * @param inputStream Input stream
85 * @return the total number of bytes read into the buffer, or
86 * {@code -1} if there is no more data because the end of
87 * the stream has been reached.
88 * @throws IOException if an I/O error occurs.
89 */
90 int read(byte[] b, int off, int len, InputStream inputStream) throws IOException;
91
92 /**
93 * Reads some number of bytes from the session buffer and stores them into
94 * the buffer array {@code b}. The number of bytes actually read is
95 * returned as an integer. This method blocks until input data is
96 * available, end of file is detected, or an exception is thrown.
97 *
98 * @param b the buffer into which the data is read.
99 * @param inputStream Input stream
100 * @return the total number of bytes read into the buffer, or
101 * {@code -1} is there is no more data because the end of
102 * the stream has been reached.
103 * @throws IOException if an I/O error occurs.
104 */
105 int read(byte[] b, InputStream inputStream) throws IOException;
106
107 /**
108 * Reads the next byte of data from this session buffer. The value byte is
109 * returned as an {@code int} in the range {@code 0} to
110 * {@code 255}. If no byte is available because the end of the stream
111 * has been reached, the value {@code -1} is returned. This method
112 * blocks until input data is available, the end of the stream is detected,
113 * or an exception is thrown.
114 *
115 * @param inputStream Input stream
116 * @return the next byte of data, or {@code -1} if the end of the
117 * stream is reached.
118 * @throws IOException if an I/O error occurs.
119 */
120 int read(InputStream inputStream) throws IOException;
121
122 /**
123 * Reads a complete line of characters up to a line delimiter from this
124 * session buffer into the given line buffer. The number of chars actually
125 * read is returned as an integer. The line delimiter itself is discarded.
126 * If no char is available because the end of the stream has been reached,
127 * the value {@code -1} is returned. This method blocks until input
128 * data is available, end of file is detected, or an exception is thrown.
129 * <p>
130 * The choice of a char encoding and line delimiter sequence is up to the
131 * specific implementations of this interface.
132 *
133 * @param buffer the line buffer, one line of characters upon return
134 * @param inputStream Input stream
135 * @return the total number of bytes read into the buffer, or
136 * {@code -1} is there is no more data because the end of
137 * the stream has been reached.
138 * @throws IOException if an I/O error occurs.
139 */
140 int readLine(CharArrayBuffer buffer, InputStream inputStream) throws IOException;
141
142 /**
143 * Returns {@link HttpTransportMetrics} for this session buffer.
144 *
145 * @return transport metrics.
146 */
147 HttpTransportMetrics getMetrics();
148
149 }