UUID.java-J2ME 中javax.bluetooth里的UUID生成类

 /* * * * Portions Copyright 2000-2007 Sun Microsystems, Inc. All Rights * Reserved. Use is subject to license terms. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version * 2 only, as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 for more details (a copy is * included at /legal/license.txt). * * You should have received a copy of the GNU General Public License * version 2 along with this work; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 or visit www.sun.com if you need additional * information or have any questions. */ /* * (c) Copyright 2001, 2002 Motorola, Inc. ALL RIGHTS RESERVED. */ package javax.bluetooth; /** * This class is defined by the JSR-82 specification * Java™ APIs for Bluetooth™ Wireless Technology, * Version 1.1. */ // JAVADOC COMMENT ELIDED public class UUID { // JAVADOC COMMENT ELIDED private long highBits; // JAVADOC COMMENT ELIDED private long lowBits; // JAVADOC COMMENT ELIDED private static final long BASE_UUID_HIGHT = 0x1000L; // JAVADOC COMMENT ELIDED private static final long BASE_UUID_LOW = 0x800000805F9B34FBL; // JAVADOC COMMENT ELIDED private static final char[] digits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' }; // JAVADOC COMMENT ELIDED public UUID(long uuidValue) { // check the specified value is out of range if (uuidValue < 0 || uuidValue > 0xffffffffL) { throw new IllegalArgumentException( "The 'uuidValue' is out of [0, 2^32 - 1] range: " + uuidValue); } /* * Create a UUID from 16/32 bits value. * * 128_bit_value = 16_bit_value * 2^96 + Bluetooth_Base_UUID * 128_bit_value = 32_bit_value * 2^96 + Bluetooth_Base_UUID * * No need to check the "overflow/negative", because * uuidValue is 32 bits & BASE_UUID_HIGHT is 16 bits. */ highBits = (uuidValue << 32) | BASE_UUID_HIGHT; lowBits = BASE_UUID_LOW; } // JAVADOC COMMENT ELIDED public UUID(String uuidValue, boolean shortUUID) { if (uuidValue == null) { throw new NullPointerException("Specified 'uuidValue' is null"); } /* * The zero length is double checked by the parsing operation, * but the NumberFormatException is thrown in that case - * we need IllegalArgumentException according to spec. */ if (uuidValue.length() == 0 || (shortUUID && uuidValue.length() > 8) || uuidValue.length() > 32) { throw new IllegalArgumentException( "Invalid length of specified 'uuidValue': " + uuidValue.length()); } // check if sign character presents if (uuidValue.indexOf('-') != -1) { throw new NumberFormatException( "The '-' character is not allowed: " + uuidValue); } /* * 16-bit or 32-bit UUID case. */ if (shortUUID) { // this checks the format and may throw a NumberFormatException long val = Long.parseLong(uuidValue, 16); /* * create a UUID from 16/32 bits value. * * No need to check the "overflow/negative", because * lVal is 32 bits & BASE_UUID_HIGHT is 16 bits. */ highBits = (val << 32) | BASE_UUID_HIGHT; lowBits = BASE_UUID_LOW; return; } /* * 128-bit UUID case. */ highBits = 0x0L; // simple case (optimization) if (uuidValue.length() < 16) { lowBits = Long.parseLong(uuidValue, 16); return; } /* * We have to do a 32 bits parsing, because the * Long.parseLong("ffff ffff ffff ffff") does not * parse such an unsigned number. */ int l = uuidValue.length(); lowBits = Long.parseLong(uuidValue.substring(l - 8), 16); lowBits |= (Long.parseLong(uuidValue.substring(l - 16, l - 8), 16) << 32); if (l == 16) { return; } if (l <= 24) { highBits = Long.parseLong(uuidValue.substring(0, l - 16), 16); } else { highBits = Long.parseLong(uuidValue.substring(l - 24, l - 16), 16); highBits |= (Long.parseLong(uuidValue.substring(0, l - 24), 16) << 32); } } // JAVADOC COMMENT ELIDED public String toString() { /* * This implementation is taken from cldc1.1 Integer#toUnsignedString * one. The implementation which uses Integer#toHexString() is * 2-3 times slower, so such a code duplication is required here. */ int[] ints = new int[] { (int) (lowBits & 0xffffffffL), (int) (lowBits >>> 32 & 0xffffffffL), (int) (highBits & 0xffffffffL), (int) (highBits >>> 32 & 0xffffffffL) }; int charPos = 32; char[] buf = new char[charPos]; int shift = 4; int mask = 0xf; int needZerosIndex = -1; /* * check with part of value requires the zero characters. * * I.e. the original algorithm gives as an 1 character * for the value '1', but we may want 00000001. */ for (int i = 3; i >= 0; i--) { if (ints[i] != 0) { needZerosIndex = i - 1; break; } } /* * Process parts of UUID from low parts to high ones. */ for (int i = 0; i < ints.length; i++) { /* * The 16 bits are zero & no need to fill with 0, * and it's not a UUID with value '0' (i != 0). */ if (ints[i] == 0 && needZerosIndex < i && i != 0) { continue; } if (needZerosIndex >= i) { // fill all 8 characters (even if allof them are '0') for (int j = 0; j < 8; j++) { buf[--charPos] = digits[ints[i] & mask]; ints[i] >>>= shift; } } else { // fill until the highest valuable character do { buf[--charPos] = digits[ints[i] & mask]; ints[i] >>>= shift; } while (ints[i] != 0); } } return new String(buf, charPos, (32 - charPos)); } // JAVADOC COMMENT ELIDED public boolean equals(Object value) { return value instanceof UUID && lowBits == ((UUID) value).lowBits && highBits == ((UUID) value).highBits; } // JAVADOC COMMENT ELIDED public int hashCode() { return (int) (highBits ^ highBits >> 32 ^ lowBits ^ lowBits >> 32); } } // end of class 'UUID' definition

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