| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
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| 3.25;3.25 |
| 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.commons.id.uuid; | |
| 18 | ||
| 19 | /** | |
| 20 | * <p>Static methods for managing byte arrays (all methods follow Big | |
| 21 | * Endian order where most significant bits are in front).</p> | |
| 22 | * | |
| 23 | * @author Commons-Id Team | |
| 24 | * @version $Id: Bytes.java 480488 2006-11-29 08:57:26Z bayard $ | |
| 25 | */ | |
| 26 | public final class Bytes { | |
| 27 | ||
| 28 | /** | |
| 29 | * <p>Hide constructor in utility class.</p> | |
| 30 | */ | |
| 31 | 0 | private Bytes() { |
| 32 | 0 | } |
| 33 | ||
| 34 | /** | |
| 35 | * Appends two bytes array into one. | |
| 36 | * | |
| 37 | * @param a A byte[]. | |
| 38 | * @param b A byte[]. | |
| 39 | * @return A byte[]. | |
| 40 | */ | |
| 41 | public static byte[] append(byte[] a, byte[] b) { | |
| 42 | 1 | byte[] z = new byte[a.length + b.length]; |
| 43 | 1 | System.arraycopy(a, 0, z, 0, a.length); |
| 44 | 1 | System.arraycopy(b, 0, z, a.length, b.length); |
| 45 | 1 | return z; |
| 46 | } | |
| 47 | ||
| 48 | /** | |
| 49 | * Returns a 8-byte array built from a long. | |
| 50 | * | |
| 51 | * @param n The number to convert. | |
| 52 | * @return A byte[]. | |
| 53 | */ | |
| 54 | public static byte[] toBytes(long n) { | |
| 55 | 3 | return toBytes(n, new byte[8]); |
| 56 | } | |
| 57 | ||
| 58 | /** | |
| 59 | * Build a 8-byte array from a long. No check is performed on the | |
| 60 | * array length. | |
| 61 | * | |
| 62 | * @param n The number to convert. | |
| 63 | * @param b The array to fill. | |
| 64 | * @return A byte[]. | |
| 65 | */ | |
| 66 | public static byte[] toBytes(long n, byte[] b) { | |
| 67 | 3 | b[7] = (byte) (n); |
| 68 | 3 | n >>>= 8; |
| 69 | 3 | b[6] = (byte) (n); |
| 70 | 3 | n >>>= 8; |
| 71 | 3 | b[5] = (byte) (n); |
| 72 | 3 | n >>>= 8; |
| 73 | 3 | b[4] = (byte) (n); |
| 74 | 3 | n >>>= 8; |
| 75 | 3 | b[3] = (byte) (n); |
| 76 | 3 | n >>>= 8; |
| 77 | 3 | b[2] = (byte) (n); |
| 78 | 3 | n >>>= 8; |
| 79 | 3 | b[1] = (byte) (n); |
| 80 | 3 | n >>>= 8; |
| 81 | 3 | b[0] = (byte) (n); |
| 82 | ||
| 83 | 3 | return b; |
| 84 | } | |
| 85 | ||
| 86 | /** | |
| 87 | * Build a long from first 8 bytes of the array. | |
| 88 | * | |
| 89 | * @param b The byte[] to convert. | |
| 90 | * @return A long. | |
| 91 | */ | |
| 92 | public static long toLong(byte[] b) { | |
| 93 | 2 | return ((((long) b[7]) & 0xFF) |
| 94 | + ((((long) b[6]) & 0xFF) << 8) | |
| 95 | + ((((long) b[5]) & 0xFF) << 16) | |
| 96 | + ((((long) b[4]) & 0xFF) << 24) | |
| 97 | + ((((long) b[3]) & 0xFF) << 32) | |
| 98 | + ((((long) b[2]) & 0xFF) << 40) | |
| 99 | + ((((long) b[1]) & 0xFF) << 48) | |
| 100 | + ((((long) b[0]) & 0xFF) << 56)); | |
| 101 | } | |
| 102 | ||
| 103 | /** | |
| 104 | * Compares two byte arrays for equality. | |
| 105 | * | |
| 106 | * @param a A byte[]. | |
| 107 | * @param b A byte[]. | |
| 108 | * @return True if the arrays have identical contents. | |
| 109 | */ | |
| 110 | public static boolean areEqual(byte[] a, byte[] b) { | |
| 111 | 23 | int aLength = a.length; |
| 112 | 23 | if (aLength != b.length) { |
| 113 | 0 | return false; |
| 114 | } | |
| 115 | ||
| 116 | 327 | for (int i = 0; i < aLength; i++) { |
| 117 | 308 | if (a[i] != b[i]) { |
| 118 | 4 | return false; |
| 119 | } | |
| 120 | } | |
| 121 | 19 | return true; |
| 122 | } | |
| 123 | ||
| 124 | /** | |
| 125 | * <p>Compares two byte arrays as specified by <code>Comparable</code>. | |
| 126 | * | |
| 127 | * @param lhs - left hand value in the comparison operation. | |
| 128 | * @param rhs - right hand value in the comparison operation. | |
| 129 | * @return a negative integer, zero, or a positive integer as <code>lhs</code> | |
| 130 | * is less than, equal to, or greater than <code>rhs</code>. | |
| 131 | */ | |
| 132 | public static int compareTo(byte[] lhs, byte[] rhs) { | |
| 133 | 3 | if (lhs == rhs) { |
| 134 | 0 | return 0; |
| 135 | } | |
| 136 | 3 | if (lhs == null) { |
| 137 | 0 | return -1; |
| 138 | } | |
| 139 | 3 | if (rhs == null) { |
| 140 | 0 | return +1; |
| 141 | } | |
| 142 | 3 | if (lhs.length != rhs.length) { |
| 143 | 0 | return ((lhs.length < rhs.length) ? -1 : +1); |
| 144 | } | |
| 145 | 33 | for (int i = 0; i < lhs.length; i++) { |
| 146 | 32 | if (lhs[i] < rhs[i]) { |
| 147 | 1 | return -1; |
| 148 | 31 | } else if (lhs[i] > rhs[i]) { |
| 149 | 1 | return 1; |
| 150 | } | |
| 151 | } | |
| 152 | 1 | return 0; |
| 153 | } | |
| 154 | ||
| 155 | /** | |
| 156 | * Build a short from first 2 bytes of the array. | |
| 157 | * | |
| 158 | * @param b The byte[] to convert. | |
| 159 | * @return A short. | |
| 160 | */ | |
| 161 | public static short toShort(byte[] b) { | |
| 162 | 12 | return (short) ((b[1] & 0xFF) + ((b[0] & 0xFF) << 8)); |
| 163 | } | |
| 164 | } |