Java: do something x percent of the time

Question

I need a few lines of Java code that run a command x percent of the time at random.

psuedocode:

boolean x = true 10% of cases.

if(x){
  System.out.p         


        

Answer 1

You just need something like this:

Random rand = new Random();

if (rand.nextInt(10) == 0) {
    System.out.println("you got lucky");
}

Here's a full example that measures it:

import java.util.Random;

public class Rand10 {
    public static void main(String[] args) {
        Random rand = new Random();
        int lucky = 0;
        for (int i = 0; i < 1000000; i++) {
            if (rand.nextInt(10) == 0) {
                lucky++;
            }
        }
        System.out.println(lucky); // you'll get a number close to 100000
    }
}

If you want something like 34% you could use rand.nextInt(100) < 34.