Book Image

Spring Data

By : Petri Kainulainen
Book Image

Spring Data

By: Petri Kainulainen

Overview of this book

Spring Framework has always had a good support for different data access technologies. However, developers had to use technology-specific APIs, which often led to a situation where a lot of boilerplate code had to be written in order to implement even the simplest operations. Spring Data changed all this. Spring Data makes it easier to implement Spring-powered applications that use cloud-based storage services, NoSQL databases, map-reduce frameworks or relational databases. "Spring Data" is a practical guide that is full of step-by-step instructions and examples which ensure that you can start using the Java Persistence API and Redis in your applications without extra hassle. This book provides a brief introduction to the underlying data storage technologies, gives step-by-step instructions that will help you utilize the discussed technologies in your applications, and provides a solid foundation for expanding your knowledge beyond the concepts described in this book. You will learn an easier way to manage your entities and to create database queries with Spring Data JPA. This book also demonstrates how you can add custom functions to your repositories. You will also learn how to use the Redis key-value store as data storage and to use its other features for enhancing your applications. "Spring Data" includes all the practical instructions and examples that provide you with all the information you need to create JPA repositories with Spring Data JPA and to utilize the performance of Redis in your applications by using Spring Data Redis.
Table of Contents (13 chapters)

The publish/subscribe messaging pattern

Redis also includes an implementation of the publish/subscribe messaging pattern. This section demonstrates how we can use Spring Data Redis for the purpose of sending and receiving messages. As an example, we will modify the CRUD application that stores the contact information as JSON to send notifications when a new contact is added, contact information is updated, and a contact is deleted.

We can implement this requirement by performing the following steps:

  1. Create message listeners that process the received messages.

  2. Configure the application context of our application.

  3. Send messages by using the RedisTemplate class.

This section also describes how we can ensure that our implementation is working correctly.

Creating message listeners

There are two ways to create message listeners by using Spring Data Redis: we can implement the MessageListener interface or we can create a POJO message listener and use the MessageListenerAdapter class to delegate messages...