Spring boot - configure EntityManager

Question

I was using Google guice in my project and now I tried to convert the framework to SpringBoot totally.

I configured the Bean for persistence.xml like below in

@Autowired
@Bean(name = "transactionManager")
public LocalContainerEntityManagerFactoryBean entityManagerFactory()
{
    LocalContainerEntityManagerFactoryBean lEMF =  new LocalContainerEntityManagerFactoryBean();
    lEMF.setPersistenceUnitName("leaseManagementPU");
    lEMF.setPersistenceXmlLocation("persistence.xml");
    return lEMF;
}

Now I need to configure(Inject) EntityManager em, to do JPA operations like em.persist(), em.find etc... How do I configure, also someone try to explain this with sample code

Answer 1

With Spring Boot its not necessary to have any config file like persistence.xml. You can configure with annotations Just configure your DB config for JPA in the

application.properties

spring.datasource.driverClassName=oracle.jdbc.driver.OracleDriver
spring.datasource.url=jdbc:oracle:thin:@DB...
spring.datasource.username=username
spring.datasource.password=pass

spring.jpa.database-platform=org.hibernate.dialect....
spring.jpa.show-sql=true

Then you can use CrudRepository provided by Spring where you have standard CRUD transaction methods. There you can also implement your own SQL's like JPQL.

@Transactional
public interface ObjectRepository extends CrudRepository<Object, Long> {
...
}

And if you still need to use the Entity Manager you can create another class.

public class ObjectRepositoryImpl implements ObjectCustomMethods{

    @PersistenceContext
    private EntityManager em;

}

This should be in your pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.2.5.RELEASE</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>4.3.11.Final</version>
    </dependency>
</dependencies>