uuid in scala
scala> UUID.random
res1: io.jvm.uuid.UUID = 5f4bdbef-0417-47a6-ac9e-ffc5a4905f7f
scala> UUID(1, 2)
res2: io.jvm.uuid.UUID = 00000000-0000-0001-0000-000000000002
scala> UUID("00112233-4455-6677-8899-aAbBcCdDeEfF")
res3: io.jvm.uuid.UUID = 00112233-4455-6677-8899-aabbccddeeff