Hibernate Application

package com.jayan;

import java.util.Iterator;
import java.util.List;
import org.hibernate.Session;
import org.hibernate.Transaction;

public class Test {

 public static void main(String[] args) {
  Test tst = new Test();
  //adding records
  tst.addUser("Jayan", "Rukmal");
  tst.addUser("Shashika", "Jaya");
  tst.addTask(1, "Email", "Send birthday wish to Pubudu");
  tst.addTask(2, "SMS", "Send message to Dad");

  //  retrieving data
  tst.getFullName("Saranga");

  // full updating records
  User user = new User();
  user.setId(1);
  user.setFirstName("Jayan");
  user.setLastName("withanage");
  tst.updateUser(user);

  //partial updating records
  tst.updateLastName(2, "Pradeep");

  //deleting records
  User user1 = new User();
  user1.setId(2);
  tst.deleteUser(user1);
 }

 private void addUser(String firstName, String lastName) {

  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();

   User user = new User();

   user.setFirstName(firstName);
   user.setLastName(lastName);

   session.save(user);

   session.getTransaction().commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }
 }

 private void addTask(int userID, String title, String description) {

  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();

   Task task = new Task();

   task.setUserID(userID);
   task.setTitle(title);


   session.save(task);

   session.getTransaction().commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }
 }

 private void updateLastName(int id, String lastName) {
  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();
   String hqlUpdate = "update User u set u.lastName = :newLastName where u.id = :oldId";
   int updatedEntities = session.createQuery( hqlUpdate )
   .setString( "newLastName", lastName )
   .setInteger( "oldId", id )
   .executeUpdate();

   trns.commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }

 }

 private void updateUser(User user) {
  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();

   session.update(user);

   session.getTransaction().commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }
 }

 private void getFullName(String firstName) {
  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();
   List<User> users = session.createQuery("from User as u where u.firstName = :firstName")
   .setString( "firstName", firstName )
   .list();
   for (Iterator<User> iter = users.iterator(); iter.hasNext();) {
    User user = iter.next();
    System.out.println(user.getFirstName() +" " + user.getLastName());
   }
   trns.commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }
 }

 private void deleteUser(User user) {
  Transaction trns = null;
  Session session = Hibernate.getSessionFactory().openSession();
  try {
   trns = session.beginTransaction();

   session.delete(user);

   session.getTransaction().commit();
  } catch (RuntimeException e) {
   if(trns != null){
    trns.rollback();
   }
   e.printStackTrace();
  } finally{
   session.flush();
   session.close();
  }
 }
}