Spring Framework and JPA

To use JPA in a Spring project, we need to set up the EntityManager. This is the main part of the configuration and we can do it via a Spring factory bean. This can be either the simpler LocalEntityManagerFactoryBean or the more flexible LocalContainerEntityManagerFactoryBean.

import java.util.Properties;

import javax.sql.DataSource;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;

import org.springframework.jdbc.datasource.DriverManagerDataSource;

import org.springframework.orm.jpa.JpaTransactionManager;

import org.springframework.orm.jpa.JpaVendorAdapter;

import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;

import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;

import org.springframework.transaction.PlatformTransactionManager;

import org.springframework.transaction.annotation.EnableTransactionManagement;

import jakarta.persistence.EntityManagerFactory;

@Configuration

@EnableTransactionManagement

public class PersistenceJPAConfig {

@Bean

public LocalContainerEntityManagerFactoryBean entityManagerFactory() {

LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();

em.setDataSource(dataSource());

em.setPackagesToScan(new String[] { "com.baeldung.persistence.model" });

JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();

em.setJpaVendorAdapter(vendorAdapter);

em.setJpaProperties(additionalProperties());

return em;

}

@Bean

public DataSource dataSource() {

DriverManagerDataSource dataSource = new DriverManagerDataSource();

dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");

dataSource.setUrl("jdbc:mysql://localhost:3306/spring_jpa");

dataSource.setUsername("tutorialuser");

dataSource.setPassword("tutorialmy5ql");

return dataSource;

}

@Bean

public PlatformTransactionManager transactionManager(EntityManagerFactory emf) {

JpaTransactionManager transactionManager = new JpaTransactionManager();

transactionManager.setEntityManagerFactory(emf);

return transactionManager;

}

@Bean

public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {

return new PersistenceExceptionTranslationPostProcessor();

}

Properties additionalProperties() {

Properties properties = new Properties();

properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");

properties.setProperty("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");

return properties;

}

}