How Java random generator works?

Question

I wrote program that simulates dice roll

    Random r = new Random();
    int result = r.nextInt(6);
    System.out.println(result);

I want

Answer 1

Check How does java.util.Random work and how good is it?:

In other words, we begin with some start or "seed" number which ideally is "genuinely unpredictable", and which in practice is "unpredictable enough". For example, the number of milliseconds— or even nanoseconds— since the computer was switched on is available on most systems. Then, each time we want a random number, we multiply the current seed by some fixed number, a, add another fixed number, c, then take the result modulo another fixed number, m. The number a is generally large. This method of random number generation goes back pretty much to the dawn of computing1. Pretty much every "casual" random number generator you can think of— from those of scientific calculators to 1980s home computers to currentday C and Visual Basic library functions— uses some variant of the above formula to generate its random numbers.

And also Predicting the next Math.random() in Java