Calculator Application in java

Let us create a simple Calculator project in java. It has four options. Addition, Subtraction, Multiplication and Division.

Steps:

• Get the input from user for the type of arithmetic operation as integer(1,2,3 or 4).
• Get the two inputs from the user.
• Using switch case, choose the case according to the user input.
• Process the statement and print the output.

Program:

   import java.util.Scanner;

   public class CalculatorApp {

       public static void main(String[] args) {

           Scanner scanner1 = new Scanner(System.in);

           System.out.println("Simple Calculator Application");

           System.out.println("Choose an operation:");

           System.out.println("1. Addition");

           System.out.println("2. Subtraction");

           System.out.println("3. Multiplication");

           System.out.println("4. Division");

           int choice1 = scanner1.nextInt();

           System.out.print("Enter the first number: ");

           double no1 = scanner1.nextDouble();

           System.out.print("Enter the second number: ");

           double no2 = scanner1.nextDouble();

           double res = 0;

           switch (choice1) {

               case 1:

                   res = no1 + no2;

                   System.out.println("Addition of two numbers: " + res);

                   break;

               case 2:

                   res = no1 - no2;

                   System.out.println("Subtraction of two numbers: " + res);

                   break;

               case 3:

                   res = no1 * no2;

                   System.out.println("Multiplication of two numbers: " + res);

                   break;

               case 4:

                   if (no2 != 0) {

                       res = no1 / no2;

                       System.out.println("Division of two numbers: " + res);

                   } else {

                       System.out.println("Error: Division by zero is not allowed.");

                   }

                   break;

               default:

                   System.out.println("Invalid choice. Please select a valid operation.");

           }

           scanner1.close();

       }

   }

C:\raji\blog>javac CalculatorApp.java

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

1

Enter the first number: 56

Enter the second number: 67

Addition of two numbers: 123.0

 

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

2

Enter the first number: 78

Enter the second number: 45

Subtraction of two numbers: 33.0

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

3

Enter the first number: 34

Enter the second number: 5

Multiplication of two numbers: 170.0

 

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

4

Enter the first number: 67

Enter the second number: 4

Division of two numbers: 16.75

 

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

5

Enter the first number: 67

Enter the second number: 78

Invalid choice. Please select a valid operation.

 

C:\raji\blog>java CalculatorApp

Simple Calculator Application

Choose an operation:

1. Addition

2. Subtraction

3. Multiplication

4. Division

4

Enter the first number: 69

Enter the second number:

0

Error: Division by zero is not allowed.

Thus the simple Calculator project is written and executed successfully. Keep coding!!!!