Factorial By Recursion in Java

Factorial.cpp

#include<iostream>
using namespace std;

int factorial(int);

int main(){
    int number, factorialOfNumber;
    cout << "Enter a number you want to calculate factorial : ";
    cin >> number;

    factorialOfNumber = factorial(number);
    cout << "Factorial of number is : " <<  factorialOfNumber << endl;
    return 0; 
}

int factorial(int number){
    if(number == 1){
        return 1;
    }else{
        return number * factorial(number - 1);
    }
}

Factorial.java

public class Factorial{

    private int number;

    // Setter for number.
    public void setNumber(int number){
        this.number = number;
    }

    // Getter for number.
    public int getNumber(){
        return this.number;
    }

    // Getter for factorial number.
    public int getFactNumber(){
        return this.factorial(this.number);
    }

    // Function that calculates factorial of a number by recursion.
    public int factorial (int number){
        // Factorial of 0 is suppossed to be 1.
        if(number == 0){
            return 1;
        }else{
            // This code implements recursion.
            return number * factorial(number - 1);
        }
    }
}

FactorialDemo.java

class FactorialDemo{
    public static void main(String[] args){
        Factorial numberOne = new Factorial();
        numberOne.setNumber(5);
        
        System.out.println("Factorial of "+numberOne.getNumber()+" is "+numberOne.getFactNumber());
    }
}