Book Image

Developing Java Applications with Spring and Spring Boot

By : Claudio Eduardo de Oliveira, Greg L. Turnquist, Alex Antonov
Book Image

Developing Java Applications with Spring and Spring Boot

By: Claudio Eduardo de Oliveira, Greg L. Turnquist, Alex Antonov

Overview of this book

Spring Framework has become the most popular framework for Java development. It not only simplifies software development but also improves developer productivity. This book covers effective ways to develop robust applications in Java using Spring. The course is up made of three modules, each one having a take-away relating to building end-to-end java applications. The first module takes the approach of learning Spring frameworks by building applications.You will learn to build APIs and integrate them with popular fraemworks suh as AngularJS, Spring WebFlux, and Spring Data. You will also learn to build microservices using Spring's support for Kotlin. You will learn about the Reactive paradigm in the Spring architecture using Project Reactor. In the second module, after getting hands-on with Spring, you will learn about the most popular tool in the Spring ecosystem-Spring Boot. You will learn to build applications with Spring Boot, bundle them, and deploy them on the cloud. After learning to build applications with Spring Boot, you will be able to use various tests that are an important part of application development. We also cover the important developer tools such as AMQP messaging, websockets, security, and more. This will give you a good functional understanding of scalable development in the Spring ecosystem with Spring Boot. In the third and final module, you will tackle the most important challenges in Java application development with Spring Boot using practical recipes. Including recipes for testing, deployment, monitoring, and securing your applications. This module will also address the functional and technical requirements for building enterprise applications. By the end of the course you will be comfortable with using Spring and Spring Boot to develop Java applications and will have mastered the intricacies of production-grade applications.
Table of Contents (34 chapters)
Title Page - Courses
Copyright and Credits - Courses
Packt Upsell - Courses

Illustrating how going from async to sync can be easy, but the opposite is not

Invariably, the question comes along--Do I need a synchronous or asynchronous API?

It's important to understand that reactive programming is not very effective unless the entire stack is reactive. Otherwise, we're simply blocking at some point, which causes the backpressure to not achieve much. That's a long-winded way of saying there is little value in making the web layer reactive if the underlying services are not.

However, it is very likely that we may produce a chunk of code that must be tapped by a non-reactive layer, hence, we have to wrap our asynchronous, non-blocking code with the means to block.

Let's explore async-to-sync by creating a BlockingImageService. This service will, basically, leverage the already written ImageService, but not include any of Reactor's Flux or Mono types in its method signatures.

We can start with a class definition as follows:

    public class BlockingImageService {