I wrote the UUID generator/parser for Ruby, so I consider myself to be reasonably well-informed on the subject. There are four major UUID versions: Version 4 UUIDs are essentially just 16 bytes of randomness pulled from a cryptographically secure random number generator, with some bit-twiddling to identify the UUID version and variant. These are extremely … Read more
There is an official implementation by Google: https://github.com/google/uuid Generating a version 4 UUID works like this: package main import ( “fmt” “github.com/google/uuid” ) func main() { id := uuid.New() fmt.Println(id.String()) } Try it here: https://play.golang.org/p/6YPi1djUMj9
Section 3 of RFC4122 provides the formal definition of UUID string representations. It’s 36 characters (32 hex digits + 4 dashes). Sounds like you need to figure out where the invalid 60-char IDs are coming from and decide 1) if you want to accept them, and 2) what the max length of those IDs might … Read more
My DBA asked me when I asked about the best way to store GUIDs for my objects why I needed to store 16 bytes when I could do the same thing in 4 bytes with an Integer. Since he put that challenge out there to me I thought now was a good time to mention … Read more
You are probably looking for System.Guid.NewGuid().
Type 3 and Type 5 UUIDs are just a technique of stuffing a hash into a UUID: Type 1: stuffs MAC address+datetime into 128 bits Type 3: stuffs an MD5 hash into 128 bits Type 4: stuffs random data into 128 bits Type 5: stuffs an SHA1 hash into 128 bits Type 6: unofficial idea … Read more
You can use this (Swift 3): UIDevice.current.identifierForVendor!.uuidString For older versions: UIDevice.currentDevice().identifierForVendor or if you want a string: UIDevice.currentDevice().identifierForVendor!.UUIDString There is no longer a way to uniquely identify a device after the user uninstalled the app(s). The documentation says: The value in this property remains the same while the app (or another app from the same … Read more
This does it: public static void main(String[] args) { final String uuid = UUID.randomUUID().toString().replace(“-“, “”); System.out.println(“uuid = ” + uuid); }
[[UIDevice currentDevice] uniqueIdentifier] Returns the Unique ID of your iPhone. EDIT: -[UIDevice uniqueIdentifier] is now deprecated and apps are being rejected from the App Store for using it. The method below is now the preferred approach. If you need to create several UUID, just use this method (with ARC): + (NSString *)GetUUID { CFUUIDRef theUUID … Read more
According to the documentation, the static method UUID.randomUUID() generates a type 4 UUID. This means that six bits are used for some type information and the remaining 122 bits are assigned randomly. The six non-random bits are distributed with four in the most significant half of the UUID and two in the least significant half. … Read more