1 /****************************************************************
2 * Licensed to the Apache Software Foundation (ASF) under one *
3 * or more contributor license agreements. See the NOTICE file *
4 * distributed with this work for additional information *
5 * regarding copyright ownership. The ASF licenses this file *
6 * to you under the Apache License, Version 2.0 (the *
7 * "License"); you may not use this file except in compliance *
8 * with the License. You may obtain a copy of the License at *
9 * *
10 * http://www.apache.org/licenses/LICENSE-2.0 *
11 * *
12 * Unless required by applicable law or agreed to in writing, *
13 * software distributed under the License is distributed on an *
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
15 * KIND, either express or implied. See the License for the *
16 * specific language governing permissions and limitations *
17 * under the License. *
18 ****************************************************************/
19
20 package org.apache.james.mime4j.util;
21
22 /**
23 * An immutable sequence of bytes.
24 */
25 public interface ByteSequence {
26
27 /**
28 * An empty byte sequence.
29 */
30 ByteSequence EMPTY = new EmptyByteSequence();
31
32 /**
33 * Returns the length of this byte sequence.
34 *
35 * @return the number of <code>byte</code>s in this sequence.
36 */
37 int length();
38
39 /**
40 * Returns the <code>byte</code> value at the specified index.
41 *
42 * @param index
43 * the index of the <code>byte</code> value to be returned.
44 * @return the corresponding <code>byte</code> value
45 * @throws IndexOutOfBoundsException
46 * if <code>index < 0 || index >= length()</code>.
47 */
48 byte byteAt(int index);
49
50 /**
51 * Copies the contents of this byte sequence into a newly allocated byte
52 * array and returns that array.
53 *
54 * @return a byte array holding a copy of this byte sequence.
55 */
56 byte[] toByteArray();
57
58 }