1 /*
2 * Copyright (C) 2010, Google Inc.
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 * Utility class for character functions on raw bytes
48 * <p>
49 * Characters are assumed to be 8-bit US-ASCII.
50 */
51 public class RawCharUtil {
52 private static final boolean[] WHITESPACE = new boolean[256];
53
54 static {
55 WHITESPACE['\r'] = true;
56 WHITESPACE['\n'] = true;
57 WHITESPACE['\t'] = true;
58 WHITESPACE[' '] = true;
59 }
60
61 /**
62 * Determine if an 8-bit US-ASCII encoded character is represents whitespace
63 *
64 * @param c
65 * the 8-bit US-ASCII encoded character
66 * @return true if c represents a whitespace character in 8-bit US-ASCII
67 */
68 public static boolean isWhitespace(byte c) {
69 return WHITESPACE[c & 0xff];
70 }
71
72 /**
73 * Returns the new end point for the byte array passed in after trimming any
74 * trailing whitespace characters, as determined by the isWhitespace()
75 * function. start and end are assumed to be within the bounds of raw.
76 *
77 * @param raw
78 * the byte array containing the portion to trim whitespace for
79 * @param start
80 * the start of the section of bytes
81 * @param end
82 * the end of the section of bytes
83 * @return the new end point
84 */
85 public static int trimTrailingWhitespace(byte[] raw, int start, int end) {
86 int ptr = end - 1;
87 while (start <= ptr && isWhitespace(raw[ptr]))
88 ptr--;
89
90 return ptr + 1;
91 }
92
93 /**
94 * Returns the new start point for the byte array passed in after trimming
95 * any leading whitespace characters, as determined by the isWhitespace()
96 * function. start and end are assumed to be within the bounds of raw.
97 *
98 * @param raw
99 * the byte array containing the portion to trim whitespace for
100 * @param start
101 * the start of the section of bytes
102 * @param end
103 * the end of the section of bytes
104 * @return the new start point
105 */
106 public static int trimLeadingWhitespace(byte[] raw, int start, int end) {
107 while (start < end && isWhitespace(raw[start]))
108 start++;
109
110 return start;
111 }
112
113 private RawCharUtil() {
114 // This will never be called
115 }
116 }