In a distributed environment, using Spring Boot, cache synchronization can be achieved efficiently through _____.
- @CacheSync
- cacheSync
- distributedCaching
- distributedSync
In a distributed environment with Spring Boot, cache synchronization can be achieved efficiently through distributed caching solutions. These solutions, like Redis or Memcached, enable multiple instances of your application to share cache data, ensuring consistency and efficiency in a distributed system.
You are developing a Spring Boot application where you have to integrate OAuth2 for securing REST APIs. How would you design the OAuth2 implementation to ensure that it is modular and doesn’t impact the existing codebase significantly?
- Implement OAuth2 directly in the existing codebase, ensuring tight coupling for security.
- Create a separate module or library for OAuth2 integration and follow OAuth2 best practices.
- Implement OAuth2 as a set of API gateway filters to decouple security from the application.
- Use a third-party OAuth2 service to handle security, reducing the need for in-house integration.
To ensure modularity and minimal impact on the existing codebase, it's best to create a separate module or library for OAuth2 integration. This allows you to follow best practices for OAuth2 implementation while keeping it decoupled from the application. Tight coupling (option 1) would make the codebase harder to maintain, and using an API gateway (option 3) might not be necessary if a modular approach is preferred. Using a third-party service (option 4) might not provide the same level of control as in-house integration.
Your application has several Auto Configurations, and you notice that some beans are being overridden unintentionally. How would you resolve the bean overriding issue and ensure that the intended beans are registered?
- Adjust the bean scope to be prototype for the intended beans to avoid conflicts.
- Remove one of the conflicting Auto Configurations from the project to eliminate the possibility of bean overriding.
- Rename the beans to ensure they have unique names, preventing accidental overriding.
- Use the @Primary annotation on the intended bean definition to make it the primary candidate for injection, resolving potential conflicts.
To resolve bean overriding issues and ensure that the intended beans are registered, you can use the @Primary annotation on the bean definition of the intended bean. This annotation marks the bean as the primary candidate for injection when there are conflicts, ensuring that it's selected over others. It's a common way to resolve unintentional bean overriding in Spring Boot applications.
How can you create a custom Auto Configuration in Spring Boot?
- By adding a custom class to the "org.springframework.boot.autoconfigure" package.
- By adding a custom class to the "org.springframework.context.annotation" package.
- By configuring properties in the application.properties file.
- By modifying the Spring Boot core code.
You can create a custom Auto Configuration in Spring Boot by adding a custom class to the "org.springframework.boot.autoconfigure" package and annotating it with @Configuration and @EnableAutoConfiguration. This class should include the necessary configurations for your custom behavior. Modifying Spring Boot core code is not recommended and should be avoided.
When implementing caching in Spring Boot, how can you handle cache concurrency?
- By using a ConcurrentCacheManager as the cache manager.
- By setting the spring.cache.concurrency property in the application.properties file.
- By using the @Cacheable annotation with a sync attribute.
- By implementing custom synchronization logic in your code.
To handle cache concurrency in Spring Boot, you can use the @Cacheable annotation with a sync attribute set to true. This ensures that cacheable methods are synchronized, preventing multiple threads from recomputing the same cached value concurrently. The other options are not standard approaches to handling cache concurrency in Spring Boot, and using a ConcurrentCacheManager is not a built-in feature of Spring Boot's caching framework.
Which annotation is primarily used for writing integration tests in Spring Boot applications?
- @Autowired
- @Component
- @RunWith(SpringRunner.class)
- @SpringBootTest
The @SpringBootTest annotation is primarily used for writing integration tests in Spring Boot applications. It loads the complete Spring application context, allowing you to perform tests in a real Spring environment.
Which of the following is true about the deleteById method of a JpaRepository?
- It deletes an entity by its primary key and returns the deleted entity.
- It deletes all entities in the repository and returns the number of deletions.
- It marks the entity as "deleted" but does not physically remove it from the database.
- It is not a standard method provided by JpaRepository.
The deleteById method of a JpaRepository deletes an entity by its primary key and returns the deleted entity. This method is a convenient way to remove a specific entity from the database. The other options do not accurately describe the behavior of this method, as it neither deletes all entities nor marks an entity as "deleted" without removing it from the database.
In a Spring Boot application, the _____ annotation is used to bind the value of a method parameter to a named cookie value.
- @Cookie
- @CookieParam
- @CookieValue
- @ValueCookie
In a Spring Boot application, the @CookieValue annotation is used to bind the value of a method parameter to a named cookie value. This allows you to access and use cookies sent by the client in your controller methods. It simplifies the process of working with cookies in a Spring Boot application.
Suppose you are working on a Spring Boot project and need to ensure that certain fields in the incoming request payload are consistent with each other (e.g., startDate should be before endDate). How would you implement this validation?
- Implement field consistency checks in a custom validator.
- Perform field consistency checks in the controller layer.
- Use exception handling to enforce field consistency.
- Use the @AssertTrue annotation for field consistency checks.
To enforce consistency between certain fields in the incoming request payload in a Spring Boot project, implementing field consistency checks in a custom validator is a suitable approach. The @AssertTrue annotation is typically used for boolean conditions, and exception handling is not the ideal way to validate such constraints. The controller layer should primarily handle request/response handling, not field-level validation.
The _____ utility in Spring Boot allows for creating disposable instances of common databases, web browsers, or anything that can run in a Docker container, for testing.
- @Disposable
- @DockerTest
- @Profile
- @TestContainers
Spring Boot, using the @TestContainers annotation, allows you to create disposable instances of databases, web browsers, or other services in Docker containers for testing purposes. It simplifies the process of setting up and tearing down these resources for testing.