Introduction

In this demo I have used NetBeans IDE 8.2 for debugging purpose. But you can use any java programming language compiler as per your availability..

import java.util.Scanner;
public class JavaExcercise {
 
  public static void main(String[] args)
    {
        Scanner in = new Scanner(System.in);
        System.out.print("Input number: ");
        int day = in.nextInt();        
 
    if(day == 1)
    {
         System.out.println("Monday");
    }
    else if(day == 2)
    {
         System.out.println("Tuesday");
    }
    else if(day == 3)
    {
        System.out.println("Wednesday");
    }
    else if(day == 4)
    {
        System.out.println("Thursday");
    }
    else if(day == 5)
    {
        System.out.println("Friday");
    }
    else if(day == 6)
    {
        System.out.println("Saturday");
    }
    else if(day == 7)
    {
        System.out.println("Sunday");
    }
    else
    {
        System.out.println("Invalid Input! Please enter week number between 1-7.");
    }
 
    }  
}

Result