UUID : Java Glossary

// generate a 128-bit high quality random number, almost certainly unique
import java.util.UUID;

// ...

UUID u = UUID.randomUUID();
System.out.println( u );
// prints something like 2867ac57-f109-470c-abec-124deea787e1
// timelow - timemid - timehigh+ver - variant+sequence - node
// The fields have nothing to do with time in this type 4 UUID.
// They only have literal time meaning for a type 1 UUID.

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