Username Validation Parameterized

As your Java knowledge increases, you've decided to revisit the username validator from Chapter 1. Since it depends on a single output, it can be shortened using parameterization.

Consider all the failure outcomes of the isValidUsername() method. Condense them all in a single @ParameterizedTest.

This exercise is part of the course

Introduction to Testing in Java

View Course

Exercise instructions

Use the correct annotation to mark a test as a parameterized test.
Add a null input to the test.
Add the annotation to input values into the test.
Mark the value type of the inputs.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.*;

import static com.datacamp.util.testing.CustomJUnitTestLauncher.launchTestsAndPrint;
import static org.junit.jupiter.api.Assertions.*;

public class Main {
    public static void main(String[] args) {
		launchTestsAndPrint(UsernameValidatorTest.class);
    }
}

class UsernameValidator {
    public static boolean isValidUsername(String username) {
        if (username == null || username.isEmpty() || username.contains(" ")) {
            return false;
        }
        return username.length() >= 3;
    }
}

class UsernameValidatorTest {
	
    // Annotate with the correct annotation for parameterized test
    @____ 
    // Add the annotation for inputting a null input
    @____ 
    // Add the annotation for inputting values and the type of the inputs
    @____(____ = {"john doe", "jd"}) 
    void isValidUsername_returnsFalse_whenSpaces(String username) {
        boolean actual = UsernameValidator.isValidUsername(username);

        assertFalse(actual);
    }
}

Edit and Run Code