Exercise 2: Read Your Test Data From a CSV File

This exercise helps you to understand how you can read your test data from a CSV file and pass the test data to a parameterized test. Let’s start by taking a quick look at the system under test.

The Calculator class has a static method called sum() which returns the sum of two long values given as method parameters. The source code of the Calculator class looks as follows:

public class Calculator {

    public static long sum(long a, long b) {
        return a + b;

During this exercise you will create the test data that’s passed to a parameterized test method which ensures that the sum() method of the Calculator class is working as expected. You can finish this exercise by following these steps:

1. Open the CalculatorTest class that’s found from the com.cleantestautomation.junit5intro package.

2. Create the CSV file which contains the test data that’s passed to the shouldReturnCorrectSum() method.

3. Ensure that JUnit 5 reads the test data from the created CSV file when it runs your parameterized test method.

4. Run your parameterized test and make sure that all test invocations pass.