In Spring Boot, the _____ annotation is used to define a method that should be invoked to handle an exception thrown during the execution of controller methods.
- @ExceptionHandler
- @ExceptionResolver
- @ControllerAdvice
- @ExceptionAdvice
In Spring Boot, the @ExceptionHandler annotation is used to define a method that should be invoked to handle an exception thrown during the execution of controller methods. This annotation allows you to specify a method that will handle exceptions specific to a particular controller or globally across all controllers. The other options are not used for this purpose in Spring Boot.
What is the primary purpose of Connection Pooling in Spring Boot applications?
- Efficiently manage database connections
- Securely store database credentials
- Automatically create database tables
- Optimize the application's UI
The primary purpose of connection pooling in Spring Boot applications is to efficiently manage database connections. Connection pooling helps reuse and recycle database connections, reducing the overhead of creating and closing connections for each database operation. This improves the performance and scalability of Spring Boot applications. The other options are not the primary purpose of connection pooling.
In a Spring Boot application, how can you specify the conditions under which a method's cache can be evicted?
- By using the @CacheEvict annotation and specifying the condition attribute.
- By calling the cache.evict() method with a condition check in your code.
- By setting the spring.cache.eviction property in the application.properties file.
- By using the @EvictionCondition annotation.
You can specify the conditions under which a method's cache can be evicted in a Spring Boot application by using the @CacheEvict annotation and specifying the condition attribute. This attribute allows you to define a SpEL (Spring Expression Language) expression that determines whether the eviction should occur. The other options are not standard ways to specify eviction conditions in Spring Boot and are not recommended practices.
In Spring Security, which interface is primarily used to load user-specific data?
- Authentication Manager
- Authentication Provider
- Security Context
- UserDetailsService
In Spring Security, the UserDetailsService interface is primarily used to load user-specific data. It is crucial for retrieving user details, including username, password, and authorities, which are necessary for authentication and authorization. The Authentication Manager is responsible for managing authentication requests, and the Authentication Provider performs the actual authentication based on the loaded user data. The Security Context stores the security-related information but is not primarily used for loading user data.
Imagine you are developing a complex Spring Boot application with custom beans, controllers, services, and repositories. How would you effectively utilize different annotations for a clean and maintainable code structure?
- @Component for beans, @Controller for web controllers, @Service for business logic, and @Repository for data access.
- @SpringBootApplication for all components.
- @Entity for beans, @RestController for web controllers, @Service for business logic, and @Resource for data access.
- @Configuration for all components.
In a complex Spring Boot application, proper annotation usage is crucial for clean and maintainable code. Use @Component for general beans, @Controller for web controllers, @Service for business logic, and @Repository for data access. This follows the recommended Spring Boot convention, ensuring a clear and structured codebase. The other options mix annotations inappropriately or use annotations that don't align with their intended purposes.
When designing RESTful APIs in Spring Boot, the _____ annotation can be used to handle HTTP GET requests specifically.
- @PostMapping
- @GetMapping
- @RequestMapping
- @RequestHeader
In Spring Boot, the @GetMapping annotation is specifically used to handle HTTP GET requests. It maps a method to a GET request for a particular URI, making it a crucial part of designing RESTful APIs in Spring Boot. The other options are used for different HTTP request types and are not suitable for handling GET requests.
How can you handle concurrent session control in a Spring Security application?
- Configure the concurrency-control element in XML config.
- Use the @EnableConcurrentSession annotation.
- Set session.concurrency property in application.properties.
- Implement a custom ConcurrentSessionControlStrategy.
Concurrent session control in Spring Security is handled by using the @EnableConcurrentSession annotation along with configuring maxSessions. Options 1, 3, and 4 are not the standard approaches for handling concurrent sessions in Spring Security.
Which of the following is true regarding Reactive Data Repositories in Spring Boot?
- Reactive Data Repositories allow blocking operations.
- Reactive Data Repositories are not suitable for real-time applications.
- Reactive Data Repositories are used for relational databases only.
- Reactive Data Repositories provide non-blocking, reactive access to data.
Regarding Reactive Data Repositories in Spring Boot, the true statement is that they provide non-blocking, reactive access to data. Reactive Data Repositories, often used with technologies like Spring Data R2DBC, enable developers to work with data in a reactive way. This means that database operations can be executed asynchronously and efficiently, making them suitable for building high-performance, non-blocking applications. Reactive Data Repositories are not limited to relational databases and can be used with various data stores.
You are assigned to write unit tests for a Spring Boot application where a method in the service layer is interacting with the database. How would you test this method ensuring that any interaction with the database is mocked?
- Use a live database for testing to ensure realistic results.
- Configure a separate test database for unit tests.
- Use a database mocking framework like H2 for testing.
- Manually mock the database interactions in the test code.
To ensure that database interactions are mocked in unit tests, you should use a database mocking framework like H2 or configure a separate test database. This allows you to simulate database behavior without connecting to a live database.
Suppose you are working on a Spring Boot project where you have to switch between different database configurations based on the environment (dev, test, prod). How would you manage and implement the configuration properties for different environments efficiently?
- Embed configuration properties directly in the application code to avoid external dependencies.
- Store configuration properties in a database and fetch them dynamically based on the environment.
- Use Spring Boot's profiles and externalized configuration to maintain separate property files for each environment.
- Use a single configuration file for all environments and rely on runtime flags to switch between configurations.
In Spring Boot, you can efficiently manage configuration properties for different environments by using profiles and externalized configuration. This approach allows you to maintain separate property files for each environment (e.g., application-dev.properties, application-test.properties, application-prod.properties) and activate the appropriate profile at runtime. Embedding properties directly in code or using a single file for all environments can lead to maintenance challenges and lack of flexibility. Storing properties in a database introduces unnecessary complexity.