12 Using data sources in Spring apps

Almost every app today needs to store data it works with. And most often, apps use databases to manage the data they persist. For many years, relational databases have provided applications with a simple and elegant way to store data that you can successfully apply in many scenarios. Spring apps, like other apps, often need to use databases to persist data, and for this reason, you need to learn how to implement such capabilities for your Spring apps.

In this chapter, we discuss what a data source is and the most straightforward way to make your Spring app work with a database. That straightforward way is the JdbcTemplate tool that Spring offers.

Figure 12.1 shows your progress in previous chapters on learning to use Spring to implement various fundamental capabilities in a system. As you observe, we made good progress, and you now can use Spring to implement capabilities in various parts of a system.

12.1  What a data source is

12.2  Using JdbcTemplate to work with persisted data

12.3  Customizing the configuration of the data source

12.3.1    Defining the data source in the application properties file

12.3.2    Using a custom DataSource bean

12.4  Summary