In this chapter, we have learned that:
Java Persistence API was introduced to address the concerns related to EJB 2.x and to provide a standard approach for object-relational mapping. Its features were selected from the features of the most popular third party persistence frameworks.
Redis is an in-memory data store, which keeps its entire data set in memory, supports complex data types, can use disk as a persistent storage, and supports master-slave replication. It also has an implementation of the publish/subscribe messaging pattern.
In the next chapter we will learn how we can set up a web application project that uses Spring Data JPA and use it to implement a simple contact manager application.