Automate test using Object Mother pattern for User creation

Preconditions (3)

Step 1: Use Object Mother to create a valid User object

Step 2: Call createUser() method with the User object

Step 3: Verify that createUser() returns true indicating successful creation

✅ Expected Result: createUser() returns true for the valid User object created by Object Mother

Automation Requirements - JUnit 5

Assertions Needed:

Assert that createUser() returns true

Best Practices:

Use Object Mother pattern to create test data

Use @Test annotation for test method

Use assertTrue for assertion

Keep test method simple and focused

Automated Solution

JUnit

import static org.junit.jupiter.api.Assertions.assertTrue;
import org.junit.jupiter.api.Test;

class User {
    private int id;
    private String name;
    private String email;

    public User(int id, String name, String email) {
        this.id = id;
        this.name = name;
        this.email = email;
    }

    // getters omitted for brevity
}

class UserService {
    public boolean createUser(User user) {
        // Simulate user creation logic
        if (user == null) return false;
        if (user.email == null || user.email.isEmpty()) return false;
        return true;
    }
}

class UserObjectMother {
    public static User validUser() {
        return new User(1, "John Doe", "john.doe@example.com");
    }
}

public class UserServiceTest {

    @Test
    void testCreateUserWithValidUser() {
        UserService userService = new UserService();
        User user = UserObjectMother.validUser();
        boolean result = userService.createUser(user);
        assertTrue(result, "User creation should succeed with valid user");
    }
}

This test uses the Object Mother pattern to create a valid User object with UserObjectMother.validUser(). This keeps test data creation separate and reusable.

The UserService.createUser() method is called with this user. The test asserts that the result is true, meaning the user was created successfully.

Using @Test marks the test method for JUnit 5. The assertion assertTrue checks the expected outcome.

This approach keeps the test clean, focused, and easy to maintain.

Common Mistakes - 3 Pitfalls

Creating test data directly inside the test method instead of using Object Mother

Not using assertions to verify the result

Using JUnit 4 annotations or imports in a JUnit 5 project

Bonus Challenge

Now add data-driven testing with 3 different User objects using Object Mother

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