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if(!dojo._hasResource["dojox.uuid.generateTimeBasedUuid"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.dojo._hasResource["dojox.uuid.generateTimeBasedUuid"] = true;dojo.provide("dojox.uuid.generateTimeBasedUuid");dojox.uuid.generateTimeBasedUuid = function(/*String?*/ node){// summary:// This function generates time-based UUIDs, meaning "version 1" UUIDs.// description:// For more info, see// http://www.webdav.org/specs/draft-leach-uuids-guids-01.txt// http://www.infonuovo.com/dma/csdocs/sketch/instidid.htm// http://kruithof.xs4all.nl/uuid/uuidgen// http://www.opengroup.org/onlinepubs/009629399/apdxa.htm#tagcjh_20// http://jakarta.apache.org/commons/sandbox/id/apidocs/org/apache/commons/id/uuid/clock/Clock.html// node:// A 12-character hex string representing either a pseudo-node or// hardware-node (an IEEE 802.3 network node). A hardware-node// will be something like "017bf397618a", always with the first bit// being 0. A pseudo-node will be something like "f17bf397618a",// always with the first bit being 1.// examples:// string = dojox.uuid.generateTimeBasedUuid();// string = dojox.uuid.generateTimeBasedUuid("017bf397618a");// dojox.uuid.generateTimeBasedUuid.setNode("017bf397618a");// string = dojox.uuid.generateTimeBasedUuid(); // the generated UUID has node == "017bf397618a"var uuidString = dojox.uuid.generateTimeBasedUuid._generator.generateUuidString(node);return uuidString; // String};dojox.uuid.generateTimeBasedUuid.isValidNode = function(/*String?*/ node){var HEX_RADIX = 16;var integer = parseInt(node, HEX_RADIX);var valid = dojo.isString(node) && node.length == 12 && isFinite(integer);return valid; // Boolean};dojox.uuid.generateTimeBasedUuid.setNode = function(/*String?*/ node){// summary:// Sets the 'node' value that will be included in generated UUIDs.// node: A 12-character hex string representing a pseudoNode or hardwareNode.dojox.uuid.assert((node === null) || this.isValidNode(node));this._uniformNode = node;};dojox.uuid.generateTimeBasedUuid.getNode = function(){// summary:// Returns the 'node' value that will be included in generated UUIDs.return this._uniformNode; // String (a 12-character hex string representing a pseudoNode or hardwareNode)};dojox.uuid.generateTimeBasedUuid._generator = new function(){// Number of hours between October 15, 1582 and January 1, 1970:this.GREGORIAN_CHANGE_OFFSET_IN_HOURS = 3394248;// Number of seconds between October 15, 1582 and January 1, 1970:// dojox.uuid.generateTimeBasedUuid.GREGORIAN_CHANGE_OFFSET_IN_SECONDS = 12219292800;// --------------------------------------------------// Private variables:var _uuidPseudoNodeString = null;var _uuidClockSeqString = null;var _dateValueOfPreviousUuid = null;var _nextIntraMillisecondIncrement = 0;var _cachedMillisecondsBetween1582and1970 = null;var _cachedHundredNanosecondIntervalsPerMillisecond = null;// --------------------------------------------------// Private constants:var HEX_RADIX = 16;function _carry(/* array */ arrayA){// summary:// Given an array which holds a 64-bit number broken into 4 16-bit// elements, this method carries any excess bits (greater than 16-bits)// from each array element into the next.// arrayA: An array with 4 elements, each of which is a 16-bit number.arrayA[2] += arrayA[3] >>> 16;arrayA[3] &= 0xFFFF;arrayA[1] += arrayA[2] >>> 16;arrayA[2] &= 0xFFFF;arrayA[0] += arrayA[1] >>> 16;arrayA[1] &= 0xFFFF;dojox.uuid.assert((arrayA[0] >>> 16) === 0);}function _get64bitArrayFromFloat(/* float */ x){// summary:// Given a floating point number, this method returns an array which// holds a 64-bit number broken into 4 16-bit elements.var result = new Array(0, 0, 0, 0);result[3] = x % 0x10000;x -= result[3];x /= 0x10000;result[2] = x % 0x10000;x -= result[2];x /= 0x10000;result[1] = x % 0x10000;x -= result[1];x /= 0x10000;result[0] = x;return result; // Array with 4 elements, each of which is a 16-bit number.}function _addTwo64bitArrays(/* array */ arrayA, /* array */ arrayB){// summary:// Takes two arrays, each of which holds a 64-bit number broken into 4// 16-bit elements, and returns a new array that holds a 64-bit number// that is the sum of the two original numbers.// arrayA: An array with 4 elements, each of which is a 16-bit number.// arrayB: An array with 4 elements, each of which is a 16-bit number.dojox.uuid.assert(dojo.isArray(arrayA));dojox.uuid.assert(dojo.isArray(arrayB));dojox.uuid.assert(arrayA.length == 4);dojox.uuid.assert(arrayB.length == 4);var result = new Array(0, 0, 0, 0);result[3] = arrayA[3] + arrayB[3];result[2] = arrayA[2] + arrayB[2];result[1] = arrayA[1] + arrayB[1];result[0] = arrayA[0] + arrayB[0];_carry(result);return result; // Array with 4 elements, each of which is a 16-bit number.}function _multiplyTwo64bitArrays(/* array */ arrayA, /* array */ arrayB){// summary:// Takes two arrays, each of which holds a 64-bit number broken into 4// 16-bit elements, and returns a new array that holds a 64-bit number// that is the product of the two original numbers.// arrayA: An array with 4 elements, each of which is a 16-bit number.// arrayB: An array with 4 elements, each of which is a 16-bit number.dojox.uuid.assert(dojo.isArray(arrayA));dojox.uuid.assert(dojo.isArray(arrayB));dojox.uuid.assert(arrayA.length == 4);dojox.uuid.assert(arrayB.length == 4);var overflow = false;if(arrayA[0] * arrayB[0] !== 0){ overflow = true; }if(arrayA[0] * arrayB[1] !== 0){ overflow = true; }if(arrayA[0] * arrayB[2] !== 0){ overflow = true; }if(arrayA[1] * arrayB[0] !== 0){ overflow = true; }if(arrayA[1] * arrayB[1] !== 0){ overflow = true; }if(arrayA[2] * arrayB[0] !== 0){ overflow = true; }dojox.uuid.assert(!overflow);var result = new Array(0, 0, 0, 0);result[0] += arrayA[0] * arrayB[3];_carry(result);result[0] += arrayA[1] * arrayB[2];_carry(result);result[0] += arrayA[2] * arrayB[1];_carry(result);result[0] += arrayA[3] * arrayB[0];_carry(result);result[1] += arrayA[1] * arrayB[3];_carry(result);result[1] += arrayA[2] * arrayB[2];_carry(result);result[1] += arrayA[3] * arrayB[1];_carry(result);result[2] += arrayA[2] * arrayB[3];_carry(result);result[2] += arrayA[3] * arrayB[2];_carry(result);result[3] += arrayA[3] * arrayB[3];_carry(result);return result; // Array with 4 elements, each of which is a 16-bit number.}function _padWithLeadingZeros(/* string */ string, /* int */ desiredLength){// summary:// Pads a string with leading zeros and returns the result.// string: A string to add padding to.// desiredLength: The number of characters the return string should have.// examples:// result = _padWithLeadingZeros("abc", 6);// dojox.uuid.assert(result == "000abc");while(string.length < desiredLength){string = "0" + string;}return string; // string}function _generateRandomEightCharacterHexString() {// summary:// Returns a randomly generated 8-character string of hex digits.// FIXME: This probably isn't a very high quality random number.// Make random32bitNumber be a randomly generated floating point number// between 0 and (4,294,967,296 - 1), inclusive.var random32bitNumber = Math.floor( (Math.random() % 1) * Math.pow(2, 32) );var eightCharacterString = random32bitNumber.toString(HEX_RADIX);while(eightCharacterString.length < 8){eightCharacterString = "0" + eightCharacterString;}return eightCharacterString; // String (an 8-character hex string)}this.generateUuidString = function(/*String?*/ node){// summary:// Generates a time-based UUID, meaning a version 1 UUID.// description:// JavaScript code running in a browser doesn't have access to the// IEEE 802.3 address of the computer, so if a node value isn't// supplied, we generate a random pseudonode value instead.// node: An optional 12-character string to use as the node in the new UUID.if(node){dojox.uuid.assert(dojox.uuid.generateTimeBasedUuid.isValidNode(node));}else{if(dojox.uuid.generateTimeBasedUuid._uniformNode){node = dojox.uuid.generateTimeBasedUuid._uniformNode;}else{if(!_uuidPseudoNodeString){var pseudoNodeIndicatorBit = 0x8000;var random15bitNumber = Math.floor( (Math.random() % 1) * Math.pow(2, 15) );var leftmost4HexCharacters = (pseudoNodeIndicatorBit | random15bitNumber).toString(HEX_RADIX);_uuidPseudoNodeString = leftmost4HexCharacters + _generateRandomEightCharacterHexString();}node = _uuidPseudoNodeString;}}if(!_uuidClockSeqString){var variantCodeForDCEUuids = 0x8000; // 10--------------, i.e. uses only first two of 16 bits.var random14bitNumber = Math.floor( (Math.random() % 1) * Math.pow(2, 14) );_uuidClockSeqString = (variantCodeForDCEUuids | random14bitNumber).toString(HEX_RADIX);}// Maybe we should think about trying to make the code more readable to// newcomers by creating a class called "WholeNumber" that encapsulates// the methods and data structures for working with these arrays that// hold 4 16-bit numbers? And then these variables below have names// like "wholeSecondsPerHour" rather than "arraySecondsPerHour"?var now = new Date();var millisecondsSince1970 = now.valueOf(); // milliseconds since midnight 01 January, 1970 UTC.var nowArray = _get64bitArrayFromFloat(millisecondsSince1970);if(!_cachedMillisecondsBetween1582and1970){var arraySecondsPerHour = _get64bitArrayFromFloat(60 * 60);var arrayHoursBetween1582and1970 = _get64bitArrayFromFloat(dojox.uuid.generateTimeBasedUuid._generator.GREGORIAN_CHANGE_OFFSET_IN_HOURS);var arraySecondsBetween1582and1970 = _multiplyTwo64bitArrays(arrayHoursBetween1582and1970, arraySecondsPerHour);var arrayMillisecondsPerSecond = _get64bitArrayFromFloat(1000);_cachedMillisecondsBetween1582and1970 = _multiplyTwo64bitArrays(arraySecondsBetween1582and1970, arrayMillisecondsPerSecond);_cachedHundredNanosecondIntervalsPerMillisecond = _get64bitArrayFromFloat(10000);}var arrayMillisecondsSince1970 = nowArray;var arrayMillisecondsSince1582 = _addTwo64bitArrays(_cachedMillisecondsBetween1582and1970, arrayMillisecondsSince1970);var arrayHundredNanosecondIntervalsSince1582 = _multiplyTwo64bitArrays(arrayMillisecondsSince1582, _cachedHundredNanosecondIntervalsPerMillisecond);if(now.valueOf() == _dateValueOfPreviousUuid){arrayHundredNanosecondIntervalsSince1582[3] += _nextIntraMillisecondIncrement;_carry(arrayHundredNanosecondIntervalsSince1582);_nextIntraMillisecondIncrement += 1;if (_nextIntraMillisecondIncrement == 10000) {// If we've gotten to here, it means we've already generated 10,000// UUIDs in this single millisecond, which is the most that the UUID// timestamp field allows for. So now we'll just sit here and wait// for a fraction of a millisecond, so as to ensure that the next// time this method is called there will be a different millisecond// value in the timestamp field.while (now.valueOf() == _dateValueOfPreviousUuid) {now = new Date();}}}else{_dateValueOfPreviousUuid = now.valueOf();_nextIntraMillisecondIncrement = 1;}var hexTimeLowLeftHalf = arrayHundredNanosecondIntervalsSince1582[2].toString(HEX_RADIX);var hexTimeLowRightHalf = arrayHundredNanosecondIntervalsSince1582[3].toString(HEX_RADIX);var hexTimeLow = _padWithLeadingZeros(hexTimeLowLeftHalf, 4) + _padWithLeadingZeros(hexTimeLowRightHalf, 4);var hexTimeMid = arrayHundredNanosecondIntervalsSince1582[1].toString(HEX_RADIX);hexTimeMid = _padWithLeadingZeros(hexTimeMid, 4);var hexTimeHigh = arrayHundredNanosecondIntervalsSince1582[0].toString(HEX_RADIX);hexTimeHigh = _padWithLeadingZeros(hexTimeHigh, 3);var hyphen = "-";var versionCodeForTimeBasedUuids = "1"; // binary2hex("0001")var resultUuid = hexTimeLow + hyphen + hexTimeMid + hyphen +versionCodeForTimeBasedUuids + hexTimeHigh + hyphen +_uuidClockSeqString + hyphen + node;resultUuid = resultUuid.toLowerCase();return resultUuid; // String (a 36 character string, which will look something like "b4308fb0-86cd-11da-a72b-0800200c9a66")}}();}