Java API = Java's ready-made libraries
https://docs.oracle.com/en/java/javase/11/docs/api/index.html




Random class
nextInt(int maximum) returns a random number between [0, maximum)
https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Random.html


import java.util.Random;

public class Example {
    public static void main(String[] args){
        Random rnd = new Random();
        for (int i=0; i<5; i++) {
            System.out.println(rnd.nextInt(6) + 1);
        }
    }
}

Example output:
5
4
3
4
6