Hibernate SessionFactory Problem

[Bob Carpenter]

I'm a JSP/Struts/JDBC developer starting my first Spring/Hibernate project.

I've read many of the docs and downloaded several examples and got them running. I'm now trying to convert one of the Spring examples to use Hibernate. For those interested, I'm converting the "Spring MVC Fast Tutorial" found at http://maestric.com/doc/java/spring - SpringMVC is #3.

I successfully got the WAR deployed, but it's failing when trying to get the hibernateTemplate from the sessionFactory. During deployment the log shows that the hibernateTemplate was created but later, from my view, when I try to use hibernateTemplate.find( ) the object is null.

So, I guess I have not correctly constructed the bean that creates the sessionFactory and makes it persistent.

I add the relevant code below, but for those that want to see the full project and log you can download it from here: http://carpenterdev.com/files/myspringmvc.zip

Thanks for your help in solving this!

--Bob

myspringmvx-dao.xml:
---------------------
<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
                           http://www.springframework.org/schema/beans/spring-beans.xsd">

      <bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/test?zeroDateTimeBehavior=convertToNull"/>
        <property name="username" value="test"/>
        <property name="password" value="test"/>
      </bean>
    
      <bean id="mySessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="dataSource" ref="myDataSource"/>
        
        <property name="mappingResources">
          <list>
            <value>Car.hbm.xml</value>
            <value>Brand.hbm.xml</value>
          </list>
        </property>
        
        <property name="hibernateProperties">
          <value>hibernate.dialect=org.hibernate.dialect.MySQLDialect</value>
        </property>
      </bean>    

      <bean id="carDAO" class="springmvc.dao.CarDAOImpl">
        <property name="sessionFactory" ref="mySessionFactory"/>
      </bean>

      <bean id="brandDAO" class="springmvc.dao.BrandDAOImpl">
        <property name="sessionFactory" ref="mySessionFactory"/>
      </bean>

</beans>
---------------------

myspringmvc-servlet.xml:
-------------------------
<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <!-- CONTROLLERS -->
    <bean name="/hello_world.html" class="springmvc.web.HelloWorldController"/>	
    <bean name="/list_cars.html" class="springmvc.web.CarListController"/>
		

    <!-- IMPORTED RESOURCES -->
    <import resource="classpath:myspringmvc-dao.xml"/>

    <!-- VIEW RESOLVER -->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
      <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
      <property name="prefix" value="/jsp/"/>
      <property name="suffix" value=".jsp"/>
    </bean>
    	

    <!-- LOCALE RESOLVER -->
    <bean id="localeResolver"
	  class="org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver">
    </bean>
    
</beans>

-------------------------

Car.hbm.xml:
-----------------------------
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
    <class name="springmvc.model.Car" table="T_CAR" catalog="test">
        <id name="id" type="java.lang.Integer">
            <column name="C_UID" />
            <generator class="native"></generator>
        </id>
        <property name="brand" type="string">
            <column name="C_BRAND" not-null="true" unique="true" />
        </property>
        <property name="model" type="string">
            <column name="C_MODEL"/>
        </property>
        <property name="price" type="java.lang.Float">
            <column name="C_PRICE" />
        </property>
    </class>
</hibernate-mapping>


-----------------------------

CarDAOImpl.java:
--------------------------------
package springmvc.dao;

import java.util.List;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.logging.Logger;

import org.hibernate.SessionFactory;
import org.springframework.orm.hibernate3.HibernateTemplate;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import springmvc.model.Car;
import springmvc.model.Brand;
import org.apache.log4j.Category;

public class CarDAOImpl implements CarDAO {
    private Category logger = Category.getInstance(this.getClass());

    private HibernateTemplate hibernateTemplate;

    public void setSessionFactory(SessionFactory sessionFactory) {
        logger.info("setSessionFactory_entry");
        logger.info("setSessionFactory - sessionFactory = " +sessionFactory);

        this.hibernateTemplate = new HibernateTemplate(sessionFactory);
        logger.info("setSessionFactory - hibernateTemplate = " +hibernateTemplate);

        logger.info("setSessionFactory_exit");
    }

    @Override
    public void saveCar(Car car) {
        logger.info("saveCar_entry");
        hibernateTemplate.saveOrUpdate(car);
        logger.info("saveCar_exit");
    }

    @Override
    @SuppressWarnings("unchecked")
    public List<Car> listCar() {
        logger.info("listCar_entry");

        List<Car> result = new ArrayList<Car>();
        if(hibernateTemplate != null) {
            result = hibernateTemplate.find("from Car");
        }
        else logger.warn("listCar - WARNING: null hibernateTemplate");

//        // Test
//        result = new ArrayList<Car>();
//        Car car = new Car();
//        Brand brand = new Brand();
//        brand.setName("Foo Name");
//        brand.setId(3);
//        brand.setCountry("Foo Country");
//        car.setBrand(brand);
//        car.setId(33);
//        car.setModel("Foo Model");
//        car.setPrice(10.98F);
//        result.add(car);

        logger.info("listCar_exit");
        return result;
    }

}

--------------------------------

[Bob Carpenter]

I'm the original poster.

I edited the posting because I pasted the wrong Car.hbm.xml code.

If you read the earlier post and the Car.hbm.xml part didn't make sense, it should now.

Thanks,

--Bob

[Bob Carpenter]

I decided to give up on using HibernateDaoSupport and instead use a plain hibernate3 api.

This means that in my DAOImpl classes, where I need to get a hibernateTemplate I use an applicationContext to get the sessionFactory bean, like this:

            ClassPathXmlApplicationContext appContext = new ClassPathXmlApplicationContext("classpath:myspringmvc-dao.xml";
            SessionFactory sessionFactory = (SessionFactory) appContext.getBean("mySessionFactory"));
            HibernateTemplate hibernateTemplate = new HibernateTemplate(sessionFactory, true);

--Bob