JUnit testing divide by 0 arithmetic exception

First of all, I’m fairly new to Java & my requirement is to create a method to divide two integers and a JUnit test method for that, which is supposed to expect the divide by zero arithmetic exception. However, my test fails with an assertion error even though there’s no 0 involved in the test method. How can I fix this?

public class Calculate {

    public static int division(int num1, int num2) throws ArithmeticException {
        try {
            return num1/ num2;
        } catch (ArithmeticException e) {
            throw new ArithmeticException("Cannot divide by 0");
        }
    }

Test Method

@Test (expected = java.lang.ArithmeticException.class)
public void division() {
    int firstNum = 10;
    int secondNum = 2;
    int expected = 5;
    Calculate test = new Calculate();
    int actual = test.division(firstNum, secondNum);
    assertEquals(expected, actual);
}

>Solution :

It looks like you are trying to test everything with a single test. Instead, you should write a sepearate test for each scenario:

   // "happy path" that division works correctly
   @Test 
   public void division() {
       int firstNum = 10;
       int secondNum = 2;
       int expected = 5;
       Calculate test = new Calculate();
       int actual = test.division(firstNum, secondNum);
       assertEquals(expected, actual);
   }

   // error path that exception is thrown
   @Test (expected = java.lang.ArithmeticException.class)
   public void divisionByZero() {
       int firstNum = 10;
       int secondNum = 0;
       Calculate test = new Calculate();
       int actual = test.division(firstNum, secondNum);
   }