Java program to build a calculator

Java program to build a calculator which gives the user to select one of the options viz.,Addition, Subtraction, Multiplication, Division.
Based on the choice of the user, and already provided 2 Integer values, our program should throw a result of the respective function like adding or subtracting, etc.

Input:

5 6  <-- Numbers for which we perform arithmetic operation.
1    <-- Choice: 1.Addition 2.Subtraction 3.Multiplication 4.Division

Output:

11

Implementation:

import java.util.*; import java.lang.*; import java.io.*; class CodeRegister { public static void main (String[] args) throws java.lang.Exception { Scanner in = new Scanner(System.in); System.out.println("Enter two numbers"); int a = in.nextInt(); int b = in.nextInt(); System.out.println("Choose the operation:\n 1. Addition\n 2. Subtraction\n 3. Multiplication\n 4. Division"); int choice = in.nextInt(); switch(choice) { case 1: System.out.println(add(a,b)); break; case 2: System.out.println(sub(a,b)); break; case 3: System.out.println(mul(a,b)); break; case 4: if(b!=0) System.out.println(div(a,b)); else System.out.println("Divisor value cannot be zero"); break; } } public static int add(int a,int b) { return a+b; } public static int sub(int a,int b) { return Math.abs(a-b); } public static int mul(int a,int b) { return a*b; } public static int div(int a,int b) { return a/b; } }