Java provides a class java.util.UUID which can be used to generate a randon UUID. Here is a sample code to create a UUID.
UUID randomUUID = UUID.randomUUID(); System.out.println(randomUUID.toString());
Output:
e617f74f-d0cd-4f17-988f-5a05a94ac63e
So the above code can be used to assign ids to entities e.g;
Suppose you are writing Person java class and want each person to have a unique id, you can use UUID to create a unique id for each person object.
class Person { private UUID personUUID; private String name; private String phoneNumber; // here are getters and setters } public Person createPerson(){ Person person = new Person(); person.setPersonUUID(UUID.randomUUID()); person.setName("Obama"); return person; }