Imagine you are developing a Spring Boot application where you need to validate incoming request payloads against a complex business rule. How would you approach implementing such a validation?
- Use custom validation annotations.
- Implement validation logic in a filter or interceptor.
- Embed validation logic in the data access layer.
- Use a third-party validation library.
When dealing with complex validation rules in a Spring Boot application, one effective approach is to use custom validation annotations. This allows you to define and apply custom validation logic directly to your model classes, keeping your code clean and maintainable. While the other options may work for simpler scenarios, they are less suitable for complex business rule validation.
When dealing with multiple exception resolver beans in Spring Boot, how can you define the order of their execution?
- By configuring the 'order' property in the application.properties file.
- By setting the 'order' property in the @ExceptionHandler annotation.
- By specifying the order in which beans are defined in the application context.
- By using the @Order annotation on the exception resolver bean classes.
When dealing with multiple exception resolver beans in Spring Boot, you can define the order of their execution by using the @Order annotation on the exception resolver bean classes. This annotation allows you to specify the order in which the beans should be prioritized. Beans with lower order values are executed before those with higher order values. This approach gives you fine-grained control over the execution order of exception resolvers.
How do you access the data sent in the request body of a POST request in a Spring Boot controller method?
- Using the @RequestParam annotation.
- By retrieving it from the HttpServletRequest object.
- By declaring a method parameter annotated with @RequestBody.
- It is automatically available as a method argument.
To access the data sent in the request body of a POST request in a Spring Boot controller method, you should declare a method parameter and annotate it with @RequestBody. This annotation tells Spring to deserialize the request body data into the specified object or data type. The other options, such as @RequestParam and retrieving it from HttpServletRequest, are used for different scenarios and do not directly handle the request body of a POST request.
How do you configure a cache manager in Spring Boot?
- By adding the @Cacheable annotation to methods that should be cached.
- By modifying the 'application.properties' file with cache settings.
- By creating a custom caching class and injecting it into services.
- By disabling caching entirely in the Spring Boot application.
In Spring Boot, cache manager configuration is typically done by modifying the 'application.properties' file with cache-related settings. Spring Boot provides easy-to-use properties for configuring popular caching solutions like EhCache, Caffeine, and more. The other options are not the standard way to configure a cache manager in Spring Boot.
How can you create a custom query method in a Spring Data JPA repository?
- By defining a method with a specific naming convention.
- By using a native SQL query.
- By annotating a method with @Query and providing the JPQL query.
- By creating a new repository interface for custom queries.
In Spring Data JPA, you can create custom query methods by defining a method in your repository interface with a specific naming convention. Spring Data JPA generates the query based on the method name, eliminating the need to write explicit queries. The other options represent alternative ways to create custom queries but are not the typical approach in Spring Data JPA.
In Spring, the _____ annotation is used to indicate that a method should be invoked after the bean has been constructed and injected.
- @PostConstruct
- @Autowired
- @BeanPostProcessor
- @Inject
In Spring, the @PostConstruct annotation is used to indicate that a method should be invoked after the bean has been constructed and injected. It is commonly used for initialization tasks that need to be performed after the bean's dependencies have been injected. The other options, such as @Autowired, @BeanPostProcessor, and @Inject, serve different purposes and are not used for the same scenario.
The Spring Boot _____ properties file allows users to configure the application's settings.
- application.yml
- configuration.properties
- main.properties
- settings.xml
In Spring Boot, the "application.yml" file is commonly used to configure the application's settings. This YAML file allows users to define various properties that control the behavior of the Spring Boot application. While other file formats like .properties are also used, "application.yml" is the most common in modern Spring Boot projects.
Which of the following is not a benefit of connection pooling in Spring Boot applications?
- Efficient use of database resources.
- Improved performance through connection reuse.
- Reduced database connection overhead.
- Simplified database configuration.
Connection pooling in Spring Boot applications offers several benefits, including improved performance, efficient resource utilization, and reduced connection overhead. However, it does not simplify database configuration. Database configuration typically includes specifying the database URL, username, password, and other settings, which connection pooling does not simplify; instead, it enhances performance and resource usage.
Explain how to secure service-to-service communication in a Spring Cloud environment using Spring Security.
- By configuring a shared secret key between services for secure communication.
- By exposing REST endpoints for service authentication and using JWT tokens.
- By using HTTP Basic Authentication and securing the communication over HTTPS.
- By using OAuth2 for authentication and authorization between services.
To secure service-to-service communication in a Spring Cloud environment using Spring Security, you can use OAuth2. This involves setting up an OAuth2 authorization server and resource servers. Services authenticate and authorize using OAuth2 tokens, ensuring secure communication. Exposing REST endpoints for service authentication and using JWT tokens is one approach, but it's just a part of the broader OAuth2-based security setup. Configuring a shared secret key or using HTTP Basic Authentication doesn't provide the same level of security and flexibility as OAuth2 in a Spring Cloud environment.
In a reactive Spring Boot application, _____ is used to handle back pressure in a reactive stream.
- Backpressure
- Flux
- Mono
- Reactor
In a reactive Spring Boot application, Backpressure is used to handle back pressure in a reactive stream. Backpressure is a mechanism that allows a subscriber to signal to a publisher how many items it can consume at a time. This is essential for preventing overload and resource exhaustion in reactive streams when the publisher emits data faster than the subscriber can handle.