1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.pdfbox.io;
18
19 import java.io.IOException;
20
21 /**
22 * An interface to allow PDF files to be stored completely in memory or
23 * to use a scratch file on the disk.
24 *
25 * @author <a href="mailto:ben@benlitchfield.com">Ben Litchfield</a>
26 * @version $Revision: 1.2 $
27 */
28 public interface RandomAccess
29 {
30
31 /**
32 * Release resources that are being held.
33 *
34 * @throws IOException If there is an error closing this resource.
35 */
36 public void close() throws IOException;
37
38 /**
39 * Seek to a position in the data.
40 *
41 * @param position The position to seek to.
42 * @throws IOException If there is an error while seeking.
43 */
44 public void seek(long position) throws IOException;
45
46 /**
47 * Read a single byte of data.
48 *
49 * @return The byte of data that is being read.
50 *
51 * @throws IOException If there is an error while reading the data.
52 */
53 public int read() throws IOException;
54
55 /**
56 * Read a buffer of data.
57 *
58 * @param b The buffer to write the data to.
59 * @param offset Offset into the buffer to start writing.
60 * @param length The amount of data to attempt to read.
61 * @return The number of bytes that were actually read.
62 * @throws IOException If there was an error while reading the data.
63 */
64 public int read(byte[] b, int offset, int length) throws IOException;
65
66 /**
67 * The total number of bytes that are available.
68 *
69 * @return The number of bytes available.
70 *
71 * @throws IOException If there is an IO error while determining the
72 * length of the data stream.
73 */
74 public long length() throws IOException;
75
76 /**
77 * Write a byte to the stream.
78 *
79 * @param b The byte to write.
80 * @throws IOException If there is an IO error while writing.
81 */
82 public void write(int b) throws IOException;
83
84 /**
85 * Write a buffer of data to the stream.
86 *
87 * @param b The buffer to get the data from.
88 * @param offset An offset into the buffer to get the data from.
89 * @param length The length of data to write.
90 * @throws IOException If there is an error while writing the data.
91 */
92 public void write(byte[] b, int offset, int length) throws IOException;
93
94 }