Question

I am generating unique ID for objects to be stored

i am including the timestamp in it

but i ran the for loop

    for (int i = 0; i < 100; i++) {

        long time = Calendar.getInstance().getTimeInMillis();
        st = Integer.toHexString((int) time);
        System.out.printf("%d %s %d %n", i, st, st.length());
    }

I am not getting the Unique

I inserted Thread.sleep(15) , then it is giving me unique value

is there another way i get the unique value?

Answer 1

I’d use a simple long or int. AtomicLong.incrementAndGet is more simple and it’s thread-safe.
Another possibility is using UUID.randomUUID() but it’s an UUID, not an numeric value.