java random number between 1 and 10

We have already seen random number generator in java.In this post, we will address specific query on how to generate random number between 1 to 10.

Using random.nextInt() to generate random number between 1 and 10

We can simply use Random class’s nextInt() method to achieve this.

As the documentation says, this method call returns "a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive)", so this means if you call nextInt(10), it will generate random numbers from 0 to 9 and that’s the reason you need to add 1 to it.
Here is generic formula to generate random number in the range.

So here is the program to generate random number between 1 and 10 in java.

package org.arpit.java2blog;

import java.util.Random;

public class GenerateRandomInRangeMain {

    public static void main(String[] args) {

        System.out.println("============================");
        System.out.println("Generating 10 random integer in range of 1 to 10 using Random");
        System.out.println("============================");
        Random randomGenerator=new Random();
        for (int i = 0; i < 10; i++) {
            System.out.println(randomGenerator.nextInt(10) + 1);
        }

    }
}

When you run above program, you will get below output:

Using Math.random() to generate random number between 1 and 10

You can also use Math.random() method to random number between 1 and 10. You can iterate from min to max and use Math.ran
Here is formula for the same:

int randomNumber = (int) (Math.random()*(max-min)) + min;

Let’s see with the help of example:

public class MathRandomExample
{
    public static void main(String[] args) {
        int min = 1;
        int max = 10;
        System.out.println("============================");
        System.out.println("Generating 10 random integer in range of 1 to 10 using Math.random");
        System.out.println("============================");
        for(int i = 0; i < 5; i++) {
            int randomNumber = (int) (Math.random()*(max-min)) + min;
            System.out.println(randomNumber);
        }

    }
}

Using ThreadLocalRandom.current.nextInt() to generate random number between 1 and 10

If you want to generate random number in current thread, you can use ThreadLocalRandom.current.nextInt() to generate random number between 1 and 10.

ThreadLocalRandom was introducted in JDK 7 for managing multiple threads.

Let's see with the help of example:

import java.util.concurrent.ThreadLocalRandom;
public class ThreadLocalRandomNextIntMain
{
    public static void main(String[] args) {
        int min = 1;
        int max = 10;
        System.out.println("============================");
        System.out.println("Generating 10 random integer in range of 1 to 10 using Math.random");
        System.out.println("============================");
        for(int i = 0; i < 5; i++) {
            int randomNumber =  ThreadLocalRandom.current().nextInt(min, max) + min;
            System.out.println(randomNumber);
        }

    }
}

That's all about java random number between 1 and 10.