Spring Boot Reactive Programming MCQ

With Spring Boot's support for Reactive Programming, developers can now easily build resilient, scalable, and efficient reactive systems. For those who are just starting out or wish to reinforce their understanding, here's a set of MCQs designed to test the basics of Spring Boot Reactive Programming.

1. What is the main purpose of Reactive Programming in Spring Boot?

a) Improved UI/UX design

b) Streamlined database queries

c) Handling large amounts of data without consuming a lot of memory

d) Reducing application startup time

Answer:

c) Handling large amounts of data without consuming a lot of memory

Explanation:

Reactive Programming allows for efficient handling of large data streams with minimal memory usage, ensuring better system responsiveness.

2. Which of the following is a core component of Spring WebFlux for building reactive applications?

a) JdbcTemplate

b) RestTemplate

c) WebClient

d) JpaRepository

Answer:

c) WebClient

Explanation:

WebClient is a non-blocking, reactive client for making web requests in Spring WebFlux.

3. In reactive programming, what represents a sequence of zero or more items?

a) Single

b) Mono

c) Flux

d) Observable

Answer:

c) Flux

Explanation:

In Spring WebFlux, Flux represents a sequence of zero or more items.

4. Which reactive type represents zero or one item?

a) Single

b) Mono

c) Flux

d) Observable

Answer:

b) Mono

Explanation:

Mono represents zero or one item, making it suitable for scenarios where you expect at most one item.

5. What is backpressure in reactive systems?

a) Increasing memory consumption

b) The measure of system's reactivity

c) The mechanism where consumers inform producers about their data consumption rate

d) The delay in response due to overloaded servers

Answer:

c) The mechanism where consumers inform producers about their data consumption rate

Explanation:

Backpressure is a critical concept in reactive systems, allowing consumers to signal how much data they can handle, thereby preventing overwhelming the consumer.

6. Which annotation enables reactive programming features in a Spring Boot application?

a) @SpringBootApplication

b) @Reactive

c) @EnableReactive

d) @EnableWebFlux

Answer:

d) @EnableWebFlux

Explanation:

The @EnableWebFlux annotation is used to enable the reactive features provided by Spring WebFlux.

7. What does R2DBC stand for in the context of Spring Boot?

a) Reactive 2 Database Connection

b) Reactive Relational Database Connectivity

c) Responsive Relational Database Connectivity

d) Real 2 Database Connection

Answer:

b) Reactive Relational Database Connectivity

Explanation:

R2DBC stands for Reactive Relational Database Connectivity, which is a reactive API for relational database access.

8. How does reactive programming help in scaling applications?

a) By reducing database size

b) By optimizing algorithms

c) By utilizing system resources more efficiently under load

d) By splitting applications into microservices

Answer:

c) By utilizing system resources more efficiently under load

Explanation:

Reactive programming allows systems to handle large volumes of concurrent users or requests by using resources like threads more efficiently.

9. Which Spring module provides support for building reactive systems?

a) Spring Data

b) Spring MVC

c) Spring WebFlux

d) Spring Boot Admin

Answer:

c) Spring WebFlux

Explanation:

Spring WebFlux is the module that offers foundational support for building reactive systems in Spring.

10. For which scenario is reactive programming NOT the best choice?

a) Streaming large amounts of data

b) High concurrency

c) Simple CRUD operations with low traffic

d) Real-time data processing

Answer:

c) Simple CRUD operations with low traffic

Explanation:

For applications with simple CRUD operations and low traffic, traditional imperative programming might be more straightforward and efficient.

11. Which reactive framework is Spring WebFlux built upon?

a) Akka Streams

b) RxJava

c) Reactor

d) Vert.x

Answer:

c) Reactor

Explanation:

Spring WebFlux is built on the Reactor project, which provides support for reactive streams.

12. Which interface represents the reactive stream that can emit multiple elements?

a) Publisher

b) Subscriber

c) Producer

d) Consumer

Answer:

a) Publisher

Explanation:

The Publisher interface in the reactive streams specification can emit multiple elements to its subscribers.