Replace jpa persistence.xml with java based configuration in Spring

Jpa 's /META/INF/persistence.xml  with transaction-type set "RESOURCE_LOCAL"  can be replace in spring configuration.

The demo persistence.xml looks like below.

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1"
  xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
  <persistence-unit name="hibernate-persistence"  transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <class>com.shengwang.demo.security.model.UserEntity</class>
    <class>com.shengwang.demo.security.model.AuthorityEntity</class>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
      <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver" />
      <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/spring" />
      <property name="javax.persistence.jdbc.user" value="root" />
      <property name="javax.persistence.jdbc.password" value="IHave1Dream!" />
      <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>
      
      <!-- ================================== -->
      <!-- some optional hibernate properties -->
      <!-- ================================== -->
      <property name="hibernate.hbm2ddl.auto" value="create"/>
      <property name="hibernate.hbm2ddl.import_files" value="insert-data.sql"/>
      <property name="hibernate.ejb.naming_strategy" value="org.hibernate.cfg.ImprovedNamingStrategy"/> 
    </properties>
  </persistence-unit>
</persistence>

This xml file can be replace with following spring config.

package com.shengwang.demo;

// omit import

@Configuration
@EnableJpaRepositories(basePackages = "com.shengwang.demo.model")
public class RootConfig {

  @Bean
  public BasicDataSource dataSource() {
    // org.apache.commons.dbcp.BasicDataSource
    BasicDataSource basicDataSource = new BasicDataSource();
    basicDataSource.setDriverClassName("com.mysql.jdbc.Driver");
    basicDataSource.setUrl("jdbc:mysql://localhost:3306/spring");
    basicDataSource.setUsername("root");
    basicDataSource.setPassword("IHave1Dream!");
    return basicDataSource;
  }

  @Bean
  public LocalContainerEntityManagerFactoryBean entityManagerFactory(DataSource dataSource) {
    LocalContainerEntityManagerFactoryBean entityManagerFactory = new LocalContainerEntityManagerFactoryBean();
//    entityManagerFactory.setPersistenceUnitName("hibernate-persistence");
    entityManagerFactory.setDataSource(dataSource);
    entityManagerFactory.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
    entityManagerFactory.setJpaDialect(new HibernateJpaDialect());
    entityManagerFactory.setPackagesToScan("com.shengwang.demo.model");
    
    entityManagerFactory.setJpaPropertyMap(hibernateJpaProperties());
    return entityManagerFactory;
  }

  private Map<String, ?> hibernateJpaProperties() {
    HashMap<String, String> properties = new HashMap<>();
    properties.put("hibernate.hbm2ddl.auto", "create");
    properties.put("hibernate.show_sql", "false");
    properties.put("hibernate.format_sql", "false");
    properties.put("hibernate.hbm2ddl.import_files", "insert-data.sql");
    properties.put("hibernate.ejb.naming_strategy", "org.hibernate.cfg.ImprovedNamingStrategy");
    
    properties.put("hibernate.c3p0.min_size", "2");
    properties.put("hibernate.c3p0.max_size", "5");
    properties.put("hibernate.c3p0.timeout", "300"); // 5mins
    
    return properties;
  }

  @Bean
  public JpaTransactionManager transactionManager(EntityManagerFactory emf) {
    //org.springframework.orm.jpa.JpaTransactionManager
    JpaTransactionManager jpaTransactionManager = new JpaTransactionManager();
    jpaTransactionManager.setEntityManagerFactory(emf);
    return jpaTransactionManager;
  }

}

In the java-based config, first define a DataSource bean, then use this data source to create entityManagerFactory, finally use this entityManagerFactory bean to create a transactionManager bean.