 # Java Program to Make a Simple Calculator Using switch...case

#### In this program, you'll learn to make a simple calculator using switch..case in Java. This calculator would be able to add, subtract, multiply and divide two numbers.

To understand this example, you should have the knowledge of the following Java programming topics:

## Example: Simple Calculator using switch Statement

``````import java.util.Scanner;

public class Main {

public static void main(String[] args) {

System.out.print("Enter two numbers: ");

// nextDouble() reads the next double from the keyboard

System.out.print("Enter an operator (+, -, *, /): ");

double result;

switch (operator) {
case '+':
result = first + second;
break;

case '-':
result = first - second;
break;

case '*':
result = first * second;
break;

case '/':
result = first / second;
break;

// operator doesn't match any case constant (+, -, *, /)
default:
System.out.printf("Error! operator is not correct");
return;
}

System.out.println(first + " " + operator + " " + second + " = " + result);
}
}``````

Output

```Enter two numbers: 1.5
4.5
Enter an operator (+, -, *, /): *
1.5 * 4.5 = 6.8```

The `*` operator entered by the user is stored in the operator variable using the `next()` method of `Scanner` object.

Likewise, the two operands, 1.5 and 4.5 are stored in variables first and second respectively using the `nextDouble()` method of `Scanner` object.

Since the operator `*` matches the when condition `'*':`, the control of the program jumps to

```result = first * second;
```

This statement calculates the product and stores in the variable result and the `break`; the statement ends the switch statement.

Finally, the `printf` statement is executed.

Note: We have used the `printf()` method instead of `println`. This is because here we are printing the formatted string. To learn more, visit the Java printf() method.