Blockquote /**
- 产生32位的UUID
- Created with JetBrains WebStorm.
- User: Administrator
- Date: 12-10-24
- Time: 下午4:48
- To change this template use File | Settings | File Templates. */
// // INSTANCE SPECIFIC METHODS // exports.generatorUUID=function() { // // Loose interpretation of the specification DCE 1.1: Remote Procedure Call // since JavaScript doesn’t allow access to internal systems, the last 48 bits // of the node section is made up using a series of random numbers (6 octets long). // var dg = new Date(1582, 10, 15, 0, 0, 0, 0); var dc = new Date(); var t = dc.getTime() - dg.getTime(); var tl = getIntegerBits(t, 0, 31); var tm = getIntegerBits(t, 32, 47); var thv = getIntegerBits(t, 48, 59) + '1’; // version 1, security version is 2 var csar = getIntegerBits(rand(4095), 0, 7); var csl = getIntegerBits(rand(4095), 0, 7);
// since detection of anything about the machine/browser is far to buggy,
// include some more random numbers here
// if NIC or an IP can be obtained reliably, that should be put in
// here instead.
var n = getIntegerBits(rand(8191), 0, 7) +
getIntegerBits(rand(8191), 8, 15) +
getIntegerBits(rand(8191), 0, 7) +
getIntegerBits(rand(8191), 8, 15) +
getIntegerBits(rand(8191), 0, 15); // this last number is two octets long
return tl + tm + thv + csar + csl + n;
} ;
//Pull out only certain bits from a very large integer, used to get the time //code information for the first part of a UUID. Will return zero’s if there //aren’t enough bits to shift where it needs to. function getIntegerBits(val, start, end) { var base16 = returnBase(val, 16); var quadArray = new Array(); var quadString = '’; var i = 0; for (i = 0; i < base16.length; i++) { quadArray.push(base16.substring(i, i + 1)); } for (i = Math.floor(start / 4); i <= Math.floor(end / 4); i++) { if (!quadArray[i] || quadArray[i] == ‘’) quadString += '0’; else quadString += quadArray[i]; } return quadString; } ;
//Replaced from the original function to leverage the built in methods in //JavaScript. Thanks to Robert Kieffer for pointing this one out function returnBase(number, base) { return (number).toString(base).toUpperCase(); } ;
//pick a random number within a range of numbers //int b rand(int a); where 0 <= b <= a function rand(max) { return Math.floor(Math.random() * (max + 1)); } ;
uuid: function () {
// http://www.ietf.org/rfc/rfc4122.txt
var s = [];
var hexDigits = "0123456789abcdef";
for (var i = 0; i < 36; i++) {
s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
}
s[14] = "4"; // bits 12-15 of the time_hi_and_version field to 0010
s[19] = hexDigits.substr((s[19] & 0x3) | 0x8, 1); // bits 6-7 of the clock_seq_hi_and_reserved to 01
s[8] = s[13] = s[18] = s[23] = "-";
var uuid = s.join("");
return uuid;
}
