Spring Cloud Test 2

Question 1

In Spring, what are the IoC containers?

Accepted Answer

BeanFactory, ApplicationContext

Answer

In Spring, the primary Inversion of Control (IoC) containers are the `BeanFactory` and the `ApplicationContext`. The `BeanFactory` provides fundamental IoC capabilities for managing beans, while the `ApplicationContext` is an enhanced version that extends `BeanFactory` with additional enterprise-specific features. These features include easier integration with Spring's AOP capabilities, message resource handling, event publication, and various web application contexts, making `ApplicationContext` the preferred choice for most applications.

Question 2

In Spring, can you inject null and empty string values?

Accepted Answer

Yes

Answer

Yes, Spring fully supports injecting both `null` and empty string values into bean properties. You can explicitly specify `null` using the `<null/>` tag in XML configuration or by setting a property to `null` programmatically. Empty strings can be injected directly as `""` in XML or as a string literal in annotations, providing flexibility for various configuration and default value scenarios.

Question 3

Which of the following statements regarding dependency injection is correct?

Accepted Answer

It helps in decoupling application objects from each other.

Answer

Dependency Injection (DI) is a fundamental principle in Spring that significantly helps in decoupling application objects from each other. Instead of objects creating or looking up their dependencies, the Spring IoC container injects these dependencies into them. This loose coupling makes components more independent, easier to test in isolation, and more reusable across different parts of an application, improving overall maintainability.

Question 4

What is the scope of a global session?

Accepted Answer

This scopes a bean definition to an HTTP Application/ Global session

Answer

The `global session` scope in Spring is specifically designed for portlet-based web applications. It scopes a bean definition to the lifecycle of a global HTTP session, which is shared across all portlets within a single portlet application. This means the bean instance is created once per global session and remains available throughout the user's interaction with the entire portlet application.

Question 5

What does the ContextRefreshedEvent event entail?

Accepted Answer

This event is published when the ApplicationContext is either initialized or refreshed

Answer

The `ContextRefreshedEvent` is a crucial event published by Spring's `ApplicationContext`. This event signifies that the `ApplicationContext` has been successfully initialized or refreshed, meaning all beans have been loaded, post-processors have run, and the context is ready for use. It serves as a common hook for application components to perform tasks that require the entire context to be fully operational, such as initializing caches or starting background services.

Spring Cloud Practice Test

Spring Cloud Practice Test

Spring Cloud Test 2