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("Enter 1st number: ");
  int num1 = in.nextInt();
 
  System.out.print("Enter 2nd number: ");
  int num2 = in.nextInt();
 
  System.out.print("Enter 3rd number: ");
  int num3 = in.nextInt();
 
 
  if (num1 > num2)
   if (num1 > num3)
    System.out.println("The greatest: " + num1);
 
  if (num2 > num1)
   if (num2 > num3)
    System.out.println("The greatest: " + num2);
 
  if (num3 > num1)
   if (num3 > num2)
    System.out.println("The greatest numbers is : " + num3);
 }
}

Result