Hi all,

I am new to Hibernate. I wrote a small program to save an object into the oracle database. I am getting NullPointerException in the following

tx = session.begintransaction

Please find my code

My POJO class
===========

import java.util.Date;

public class Employee
{
private int empno;
private int deptno;
private String ename;
private String job;
private double sal;
private Date hiredate;

// Getters and Setters method
}

=================================================================================
My hbm file

<?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 package="com.saravanan.hibernate.domain">
<class name="Employee" table="emp" lazy="false">

<id name="empno" type="int">
<column name="empno" />
<generator class = "increment" />
</id>

<property name="ename" column="ename" />
<property name="sal" />
<property name="job" />
<property name="hiredate" />
<property name="deptno" />
</class>

</hibernate-mapping>

=====================================================================================

My mapping file

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

<hibernate-configuration>
<session-factory>
<property name = "connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name = "connection.url">jdbc:oracle:thin:@localhost:1030:GDN</property>
<property name = "connection.user">scott</property>
<property name = "connection.password">tiger</property>
<property name = "dialect">org.hibernate.dialect.OracleDialect</property>

<mapping resource = "com/saravanan/hibernate/mappings/Employee.hbm.xml" />

</session-factory>
</hibernate-configuration>

=====================================================================================

My test class

import org.hibernate.cfg.*;
import org.hibernate.*;
import org.apache.log4j.Logger;
import org.apache.log4j.Level;
import java.util.Date;

import com.saravanan.hibernate.domain.Employee;

public class HibernateBasicTestCase
{

private SessionFactory factory;

/**
* @param args
*/
public static void main(String[] args)
{
//Logger
HibernateBasicTestCase test = new HibernateBasicTestCase();

//Preparing Configuration object
System.out.println( "Preparing configuration object..." );
Configuration cfg = new Configuration();
cfg.configure();

//Building SessionFactory
System.out.println( "Building SessionFactory..." );
test.factory = cfg.buildSessionFactory();

System.out.println( "Building Persistant Object..." );
Employee emp = new Employee();
emp.setEname("SARAVANAN");
emp.setSal( 20000 );
emp.setJob("ASE");
emp.setHiredate( new Date() );
emp.setDeptno(20);

test.createEmployee(emp);

//updating

}

public void createEmployee( Employee emp )
{
Session session = null;
Transaction tx = null;

try
{
session = factory.openSession();
System.out.println( "Begining transaction for Saving Employee object...." );
if ( session != null )
System.out.println ("session is not null" );
tx = session.beginTransaction();

System.out.println( "Saving Employee object...." );
session.save( emp ); //Save new Employee object
tx.commit();
System.out.println( "Employee created with empno: " + emp.getEmpno() );
}
catch( HibernateException hexp )
{
tx.rollback();
System.out.println( "Exception in creating an Employee" );
}
finally
{
session.close();
}
}
}

=====================================================================================

############## My output in Eclipse #############################

Preparing configuration object...
log4j:WARN No appenders could be found for logger (org.hibernate.type.BasicTypeRegistry).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Building SessionFactory...
Building Persistant Object...
Begining transaction for Saving Employee object....
session is not null
Exception in thread "main" java.lang.NullPointerException
at com.saravanan.hibernate.test.HibernateBasicTestCase.createEmployee(HibernateBasicTestCase.java:67)
at com.saravanan.hibernate.test.HibernateBasicTestCase.main(HibernateBasicTestCase.java:41)


Kindly advise....