一、前言
关于jsr082.jar源码包中javax.bluetooth.UUID定义全局序列生成器，详情参见源码说明。
二、源码说明
 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 | package javax.bluetooth;public class UUID{ long highBits; long lowBits; private static final long BASE_UUID_HIGHT = 4096L; private static final long BASE_UUID_LOW = -9223371485494954757L; private static final char[] digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' }; public UUID(long uuidValue) { if ((uuidValue < 0L) || (uuidValue > 4294967295L)) { throw new IllegalArgumentException("The 'uuidValue' is out of [0, 2^32 - 1] range: " + uuidValue); } this.highBits = (uuidValue << 32 | 0x1000); this.lowBits = -9223371485494954757L; } public UUID(String uuidValue, boolean shortUUID) { if (uuidValue == null) { throw new NullPointerException("Specified 'uuidValue' is null"); } if ((uuidValue.length() == 0) || ((shortUUID) && (uuidValue.length() > 8)) || (uuidValue.length() > 32)) { throw new IllegalArgumentException("Invalid length of specified 'uuidValue': " + uuidValue.length()); } if (uuidValue.indexOf(45) != -1) { throw new NumberFormatException("The '-' character is not allowed: " + uuidValue); } if (shortUUID) { long val = Long.parseLong(uuidValue, 16); this.highBits = (val << 32 | 0x1000); this.lowBits = -9223371485494954757L; return; } this.highBits = 0L; if (uuidValue.length() < 16) { this.lowBits = Long.parseLong(uuidValue, 16); return; } int l = uuidValue.length(); this.lowBits = Long.parseLong(uuidValue.substring(l - 8), 16); this.lowBits |= Long.parseLong(uuidValue.substring(l - 16, l - 8), 16) << 32; if (l == 16) { return; } if (l <= 24) { this.highBits = Long.parseLong(uuidValue.substring(0, l - 16), 16); } else { this.highBits = Long.parseLong(uuidValue.substring(l - 24, l - 16), 16); this.highBits |= Long.parseLong(uuidValue.substring(0, l - 24), 16) << 32; } } public String toString() { int[] ints = { (int)(this.lowBits & 0xFFFFFFFF), (int)(this.lowBits >>> 32 & 0xFFFFFFFF), (int)(this.highBits & 0xFFFFFFFF), (int)(this.highBits >>> 32 & 0xFFFFFFFF) }; int charPos = 32; char[] buf = new char[charPos]; int shift = 4; int radix = 16; int mask = 15; int needZerosIndex = -1; for (int i = 3; i >= 0; --i) { if (ints[i] != 0) { needZerosIndex = i - 1; break; } } for (i = 0; i < ints.length; ++i) { int j; if ((ints[i] == 0) && (needZerosIndex < i) && (i != 0)) { break label226: } if (needZerosIndex >= i) { for (j = 0; j < 8; ++j) { buf[(--charPos)] = digits[(ints[i] & mask)]; ints[i] >>>= shift; } } else do { buf[(--charPos)] = digits[(ints[i] & mask)]; ints[i] >>>= shift; } while (ints[i] != 0); } label226: return new String(buf, charPos, 32 - charPos); } public boolean equals(Object value) { return ((value instanceof UUID) && (this.lowBits == ((UUID)value).lowBits) && (this.highBits == ((UUID)value).highBits)); } public int hashCode() { return (int)(this.highBits ^ this.highBits >> 32 ^ this.lowBits ^ this.lowBits >> 32); }} |
