@Component annotation in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to mark the class as a Spring component.

Spring Boot

@[1]
public class MyService {
    // service methods
}

Drag options to blanks, or click blank then click option'

ARepository

BService

CComponent

DController

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Service or @Repository instead of @Component when a generic component is needed.

Forgetting the @Component annotation, so Spring does not detect the class.

The @Component annotation tells Spring to treat this class as a component and manage its lifecycle.

2fill in blank

medium

Complete the code to inject the component into another class using Spring's annotation.

Spring Boot

public class MyController {
    @[1]
    private MyService myService;
}

Drag options to blanks, or click blank then click option'

AInject

BAutowired

CResource

DComponent

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Component instead of @Autowired for injection.

Forgetting to annotate the field or constructor for injection.

The @Autowired annotation tells Spring to inject the component automatically.

3fill in blank

hard

Fix the error in the code by completing the annotation to register the class as a Spring component.

Spring Boot

@[1]
public class DataRepository {
    public void save() {
        // save data
    }
}

Drag options to blanks, or click blank then click option'

ARepository

BComponent

CService

DController

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Component instead of @Repository for data access classes.

Not annotating the class, so Spring does not manage it.

The @Repository annotation is a specialized form of @Component for data access classes.

4fill in blank

hard

Fill both blanks to create a Spring component and inject it into another class.

Spring Boot

@[1]
public class NotificationService {
    public void notifyUser() {
        // notify logic
    }
}

public class UserController {
    @[2]
    private NotificationService notificationService;
}

Drag options to blanks, or click blank then click option'

AComponent

BAutowired

CService

DInject

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up @Service and @Component annotations.

Forgetting to use @Autowired for injection.

The @Component annotation registers the class as a Spring bean, and @Autowired injects it where needed.

5fill in blank

hard

Fill all three blanks to define a Spring component with a method and inject it properly.

Spring Boot

@[1]
public class EmailSender {
    public void sendEmail() {
        // send email logic
    }
}

public class NotificationController {
    @[2]
    private EmailSender [3];
}

Drag options to blanks, or click blank then click option'

AComponent

BAutowired

CemailSender

DService

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Service instead of @Component when a generic component is intended.

Not matching the variable name to the injected type.

@Component registers the class as a Spring bean, @Autowired injects it, and emailSender is the variable name used for the injected instance.