M03 Q21 What do you need to do in Spring if you would like to work with JPA?

Following steps are required to work with JPA in Spring Framework:

1 Declare maven dependencies:

• JPA API - javax.persistence:javax.persistence-api
• Spring ORM - org.springframework:spring-orm
• ORM of your choice, for example - org.hibernate:hibernate-core
• Database Driver, for example - org.hsqldb: hsqldb
• Optionally, but recommended, Spring Data JPA - org.springframework.data:spring-data-jpa

2 Define DataSource Bean

Also, I have JpaConfiguration. Here I added @EnableJpaRepositories annotation. It is a part of spring-data and it's not required but I want to generate DAO automatically.

3 Define PlatformTransactionManager, in case of JPA JpaTransactionManager

4 Define EntityManagerFactoryBean

• LocalContainerEntityManagerFactoryBean for standalone application
• EntityManagerFactory from JNDI
• LocalEntityManagerFactoryBean for Test purposes

Here I defined LocalContainerEntityManagerFactoryBean because I am creating a standalone application. I pointed to the package which contains data objects at setPackageToScan method. And created JpaTransactionManager bean.

5 Define @Entity classes with at least on @Id field

6 Define DAO classes, or use Spring Data JPA Repositories