- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-07 17:11:57+12:00
- Desc:
- update for modified HH graphs in tutorial description
- Permanent Source URI:
- https://models.physiomeproject.org/workspace/a1/rawfile/98909b01e6b21653a5e1cd28865dd259c586d490/dojo-presentation/js/dojo/dojox/uuid/generateRandomUuid.js
dojo.provide("dojox.uuid.generateRandomUuid");
dojox.uuid.generateRandomUuid = function(){
// summary:
// This function generates random UUIDs, meaning "version 4" UUIDs.
// description:
// A typical generated value would be something like this:
// "3b12f1df-5232-4804-897e-917bf397618a"
//
// For more information about random UUIDs, see sections 4.4 and
// 4.5 of RFC 4122: http://tools.ietf.org/html/rfc4122#section-4.4
//
// This generator function is designed to be small and fast,
// but not necessarily good.
//
// Small: This generator has a small footprint. Once comments are
// stripped, it's only about 25 lines of code, and it doesn't
// dojo.require() any other modules.
//
// Fast: This generator can generate lots of new UUIDs fairly quickly
// (at least, more quickly than the other dojo UUID generators).
//
// Not necessarily good: We use Math.random() as our source
// of randomness, which may or may not provide much randomness.
// examples:
// var string = dojox.uuid.generateRandomUuid();
var HEX_RADIX = 16;
function _generateRandomEightCharacterHexString(){
// 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 eightCharacterHexString = random32bitNumber.toString(HEX_RADIX);
while(eightCharacterHexString.length < 8){
eightCharacterHexString = "0" + eightCharacterHexString;
}
return eightCharacterHexString; // for example: "3B12F1DF"
}
var hyphen = "-";
var versionCodeForRandomlyGeneratedUuids = "4"; // 8 == binary2hex("0100")
var variantCodeForDCEUuids = "8"; // 8 == binary2hex("1000")
var a = _generateRandomEightCharacterHexString();
var b = _generateRandomEightCharacterHexString();
b = b.substring(0, 4) + hyphen + versionCodeForRandomlyGeneratedUuids + b.substring(5, 8);
var c = _generateRandomEightCharacterHexString();
c = variantCodeForDCEUuids + c.substring(1, 4) + hyphen + c.substring(4, 8);
var d = _generateRandomEightCharacterHexString();
var returnValue = a + hyphen + b + hyphen + c + d;
returnValue = returnValue.toLowerCase();
return returnValue; // String
};
