This is a Java library for generating Universally Unique Identifiers. List of implemented UUID types: UUID Version 1: the Gregorian time-based type specified in RFC-4122; UUID Version 2: the DCE Security type with embedded POSIX UIDs specified in DCE 1.1; UUID Version 3: the name-based type specified in RFC-4122 that uses MD5 hashing; UUID Version 4: the randomly or pseudo-randomly generated type