Hibernate is a famous ORM. Spring is almost universally used light-weight container.
I want to show how we can integrate a Hibernate bean program with Spring.
I am using Hibernate2 and Spring1.2
First of all I created a database in MySql.
The name of the database is springhiberdb.
This database has just one table named books.
The table has three columns.
( id, author and title) ( int(3), varchar(16),varchar(16).
I made a few entries and left it running..
My working directory is g:\springhiber
path=d:\windows\system32;c:\jdk1.5\bin;
my classpath includes the following files.
We must be very careful in this step. I had a lot of trouble as I missed one of the required jar files.
g:\springhiber;
commons-collections-2.1.1.jar;
commons-logging-1.0.4.jar;
dom4j-1.4.jar;
hibernate2.jar;
jta.jar;
log4j-1.2.9.jar;
mysqldriver.jar;
cglib-full-2.0.2.jar;
spring.jar
Any hibernate program has a database properties file, persistence mapping file and the class to be persisted.
In my case, I am persisting book.class.
book.java
public class book
{
Integer id;
String title;
String author;
public void
setId(Integer id){this.id=id;}
public Integer
getId(){return id;}
public void
setTitle(String title){this.title=title;}
public String getTitle(){return title;}
public void
setAuthor(String author){this.author=author;}
public String getAuthor(){return author;}
}
When we use Spring, we should not provide a separate hibernate.properties file.
The database details of the MySql database will be mapped in beans.xml.
Secondly, the beans.xml file will map the dialect and the class being persisted
as HibernateProperties.
( quite reasonable to deal like this).
Thirdly, the beans.xml will map our springhibernean.
So, I give the hiberbean code now .
( Spring’s hibernatetemplate takes care of all the details!)
********************************************************************************************
import java.util.*;
import net.sf.hibernate.*;
import org.springframework.dao.*;
import org.springframework.orm.hibernate.support.*;
public class springhiberbean extends HibernateDaoSupport
{
public void addbook(book book1)
{
getHibernateTemplate().save(book1);
}
}
**********************************************************
That is all!
So, let us now see the beans.xml file
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC
"-//SPRING//DTD BEAN//EN"
"http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<!--*********************************** -->
<bean id="dataSource"
class=
"org.springframework.jdbc.datasource.
DriverManagerDataSource">
<property name="driverClassName"
value= "com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost/springhiberdb"/>
<property name="username" value = "root"/>
<property name="password" value="" />
</bean>
<!--************************************* -->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate
.LocalSessionFactoryBean">
<property name="dataSource">
<ref local="dataSource" />
</property>
<property name="mappingResources">
<list>
<value>book.hbm.xml</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
net.sf.hibernate.dialect.MySQLDialect
</prop>
</props>
</property>
</bean>
<!-- *********************************** -->
<bean id="bean1" class="springhiberbean">
<property name="sessionFactory">
<ref local="sessionFactory" />
</property>
</bean>
</beans>
********************************************************************************************
Next thing is mapping xml file,
book.hbm.xml
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="book" table="books">
<id name="id" column="ID"
unsaved-value="0">
<generator class="increment"/>
</id>
<property name="title" type="string" />
<property name="author" type="string" />
</class>
</hibernate-mapping>
That is all there is to it.
Now create a client program as given below.
// userconsole.java
import org.springframework.context.*;
import org.springframework.context.support.*;
import java.util.*;
class userconsole
{
public static void main(String[] args)
{
ApplicationContext context =
new ClassPathXmlApplicationContext( "beans.xml" );
springhiberbean bean1=
(springhiberbean)context.getBean("bean1");
book book1 = new book();
book1.setTitle(args[0]);
book1.setAuthor(args[1]);
bean1.addbook(book1);
}
}
Now, compile all the java files and then execute the client program as
>java userconsole “struts” “ted-husted”
The id will be automatically incremented.
The book is added to the table.
We can see that in mysql console.
We are not writing any code atall for hibernate!
Do you remember the typical hibernate code beginning with something like
Configurartion config = new Configuration();
config.addClass(… etc?
We do not need all that now. Spring’s Hibernate Template takes care of such details.
====================================
