Hibernate 3 with Spring

1. Overview

This article will focus on setting up Hibernate 3 with Spring – we’ll look at how to configure Spring 3 with Hibernate 3 using both Java and XML Configuration.

2. Maven

To add the Spring Persistence dependencies to the pom, please see the Spring with Maven article.

Continuing with Hibernate 3, the Maven dependencies are simple:

<dependency>
   <groupId>org.hibernate</groupId>
   <artifactId>hibernate-core</artifactId>
   <version>3.6.10.Final</version>
</dependency>

Then, to enable Hibernate to use its proxy model, we need javassist as well:

<dependency>
   <groupId>org.javassist</groupId>
   <artifactId>javassist</artifactId>
   <version>3.17.1-GA</version>
</dependency>

And since we’re going to use MySQL for this tutorial, we’ll also need:

<dependency>
   <groupId>mysql</groupId>
   <artifactId>mysql-connector-java</artifactId>
   <version>5.1.25</version>
   <scope>runtime</scope>
</dependency>

3. Java Spring Configuration for Hibernate 3

Setting up Hibernate 3 with Spring and Java configuration is straightforward:

import java.util.Properties;
import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.hibernate3.HibernateTransactionManager;
import org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import com.google.common.base.Preconditions;
 
@Configuration
@EnableTransactionManagement
@PropertySource({ "classpath:persistence-mysql.properties" })
@ComponentScan({ "org.baeldung.spring.persistence" })
public class PersistenceConfig {
 
   @Autowired
   private Environment env;
 
   @Bean
   public AnnotationSessionFactoryBean sessionFactory() {
      AnnotationSessionFactoryBean sessionFactory = new AnnotationSessionFactoryBean();
      sessionFactory.setDataSource(restDataSource());
      sessionFactory.setPackagesToScan(new String[] { "org.baeldung.spring.persistence.model" });
      sessionFactory.setHibernateProperties(hibernateProperties());
 
      return sessionFactory;
   }
 
   @Bean
   public DataSource restDataSource() {
      DriverManagerDataSource dataSource = new DriverManagerDataSource();
      dataSource.setDriverClassName(env.getProperty("jdbc.driverClassName"));
      dataSource.setUrl(env.getProperty("jdbc.url"));
      dataSource.setUsername(env.getProperty("jdbc.user"));
      dataSource.setPassword(env.getProperty("jdbc.pass"));
 
      return dataSource;
   }
 
   @Bean
   public HibernateTransactionManager transactionManager() {
      HibernateTransactionManager txManager = new HibernateTransactionManager();
      txManager.setSessionFactory(sessionFactory().getObject());
 
      return txManager;
   }
 
   @Bean
   public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
      return new PersistenceExceptionTranslationPostProcessor();
   }
 
   Properties hibernateProperties() {
      return new Properties() {
         {
            setProperty("hibernate.hbm2ddl.auto", env.getProperty("hibernate.hbm2ddl.auto"));
            setProperty("hibernate.dialect", env.getProperty("hibernate.dialect"));
         }
      };
   }
}

Compared to the XML Configuration – described next – there is a small difference in the way one bean in the configuration access another. In XML there is no difference between pointing to a bean or pointing to a bean factory capable of creating that bean. Since the Java configuration is type-safe – pointing directly to the bean factory is no longer an option – we need to retrieve the bean from the bean factory manually:

txManager.setSessionFactory(sessionFactory().getObject());

4. XML Spring Configuration for Hibernate 3

Simillary, Hibernate 3 can be configured using XML Configuration as well:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xsi:schemaLocation="
      http://www.springframework.org/schema/beans
      http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context-3.2.xsd">
 
   <context:property-placeholder location="classpath:persistence-mysql.properties" />
 
   <bean id="sessionFactory"
    class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
      <property name="dataSource" ref="dataSource" />
      <property name="packagesToScan" value="org.baeldung.spring.persistence.model" />
      <property name="hibernateProperties">
         <props>
            <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>
         </props>
      </property>
   </bean>
 
   <bean id="dataSource"
    class="org.springframework.jdbc.datasource.DriverManagerDataSource">
      <property name="driverClassName" value="${jdbc.driverClassName}" />
      <property name="url" value="${jdbc.url}" />
      <property name="username" value="${jdbc.user}" />
      <property name="password" value="${jdbc.pass}" />
   </bean>
 
   <bean id="txManager"
    class="org.springframework.orm.hibernate3.HibernateTransactionManager">
      <property name="sessionFactory" ref="sessionFactory" />
   </bean>
 
   <bean id="persistenceExceptionTranslationPostProcessor"
    class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
 
</beans>

Then, this XML file is boostrapped into the Spring context:

@Configuration
@EnableTransactionManagement
@ImportResource({ "classpath:persistenceConfig.xml" })
public class PersistenceXmlConfig {
   //
}

For both types of configuration, the JDBC and Hibernate specific properties are stored in a properties file:

# jdbc.X
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/spring_hibernate_dev?createDatabaseIfNotExist=true
jdbc.user=tutorialuser
jdbc.pass=tutorialmy5ql
# hibernate.X
hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
hibernate.show_sql=false
hibernate.hbm2ddl.auto=create-drop

5. Spring, Hibernate and MySQL

The example above uses MySQL 5 as the underlying database configured with Hibernate – however, Hibernate supports several underlying SQL Databases.

5.1. The Driver

The Driver class name is configured via the jdbc.driverClassName property provided to the DataSource.

In the example above, it is set to com.mysql.jdbc.Driver from the mysql-connector-java dependency we defined in the pom, at the start of the article.

5.2. The Dialect

The Dialect is configured via the hibernate.dialect property provided to the Hibernate SessionFactory.

In the example above, this is set to org.hibernate.dialect.MySQL5Dialect as we are using MySQL 5 as the underlying Database. There are several other dialects supporting MySQL:

• org.hibernate.dialect.MySQL5InnoDBDialect – for MySQL 5.x with the InnoDB storage engine
• org.hibernate.dialect.MySQLDialect – for MySQL prior to 5.x
• org.hibernate.dialect.MySQLInnoDBDialect – for MySQL prior to 5.x with the InnoDB storage engine
• org.hibernate.dialect.MySQLMyISAMDialect – for all MySQL versions with the ISAM storage engine

Hibernate supports SQL Dialects for every supported Database.

6. Usage

At this point, Hibernate 3 is fully configured with Spring and we can inject the raw HibernateSessionFactory directly whenever we need to:

public abstract class FooHibernateDAO{
 
   @Autowired
   SessionFactory sessionFactory;
 
   ...
 
   protected Session getCurrentSession(){
      return sessionFactory.getCurrentSession();
   }
}

7. Conclusion

In this example, we configured Hiberate 3 with Spring – both with Java and XML configuration. The implementation of this simple project can be found in the github project – this is an Eclipse based project, so it should be easy to import and run as it is.