1 /*
2 * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
3 * and other copyright owners as documented in the project's IP log.
4 *
5 * This program and the accompanying materials are made available
6 * under the terms of the Eclipse Distribution License v1.0 which
7 * accompanies this distribution, is reproduced below, and is
8 * available at http://www.eclipse.org/org/documents/edl-v10.php
9 *
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
14 * conditions are met:
15 *
16 * - Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials provided
22 * with the distribution.
23 *
24 * - Neither the name of the Eclipse Foundation, Inc. nor the
25 * names of its contributors may be used to endorse or promote
26 * products derived from this software without specific prior
27 * written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
30 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
31 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
34 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 */
43
44 package org.eclipse.jgit.util;
45
46 /**
47 * A rough character sequence around a raw byte buffer.
48 * <p>
49 * Characters are assumed to be 8-bit US-ASCII.
50 */
51 public final class RawCharSequence implements CharSequence {
52 /** A zero-length character sequence. */
53 public static final RawCharSequence EMPTY = new RawCharSequence(null, 0, 0);
54
55 final byte[] buffer;
56
57 final int startPtr;
58
59 final int endPtr;
60
61 /**
62 * Create a rough character sequence around the raw byte buffer.
63 *
64 * @param buf
65 * buffer to scan.
66 * @param start
67 * starting position for the sequence.
68 * @param end
69 * ending position for the sequence.
70 */
71 public RawCharSequence(final byte[] buf, final int start, final int end) {
72 buffer = buf;
73 startPtr = start;
74 endPtr = end;
75 }
76
77 public char charAt(final int index) {
78 return (char) (buffer[startPtr + index] & 0xff);
79 }
80
81 public int length() {
82 return endPtr - startPtr;
83 }
84
85 public CharSequence subSequence(final int start, final int end) {
86 return new RawCharSequence(buffer, startPtr + start, startPtr + end);
87 }
88
89 @Override
90 public String toString() {
91 final int n = length();
92 final StringBuilder b = new StringBuilder(n);
93 for (int i = 0; i < n; i++)
94 b.append(charAt(i));
95 return b.toString();
96 }
97 }