how do I produce a random integer in Java code example

Example 1: java random numbers in specific range

import java.util.Random;

Random rand = new Random();
int random_integer = rand.nextInt(upperbound-lowerbound) + lowerbound;

Example 2: how to generate a random number in java

import java.util.Random;

Random rand = new Random();
int maxNumber = 10;

int randomNumber = rand.nextInt(maxNumber) + 1;

System.out.println(randomNumber);

Example 3: how to generate random number in java

double x = (Math.random()*((max-min)+1))+min;