hibernate basic

package de.laliluna.example;

import java.util.Iterator;
import java.util.List;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import de.laliluna.hibernate.SessionFactoryUtil;

public class TestExample {

final static Logger logger = LoggerFactory.getLogger(TestExample.class);

/**
* @param args
*/
public static void main(String[] args) {
Honey forestHoney = new Honey();
forestHoney.setName("forest honey");
forestHoney.setTaste("very sweet");
Honey countryHoney = new Honey();
countryHoney.setName("country honey");
countryHoney.setTaste("tasty");
createHoney(forestHoney);
createHoney(countryHoney);
// our instances have a primary key now:
logger.debug("{}", forestHoney);
logger.debug("{}", countryHoney);
listHoney();
deleteHoney(countryHoney);
listHoney();
forestHoney.setName("Norther Forest Honey");
updateHoney(forestHoney);

}

private static void listHoney() {
Transaction tx = null;
Session session = SessionFactoryUtil.getInstance().getCurrentSession();
try {
tx = session.beginTransaction();
List honeys = session.createQuery("select h from Honey as h")
.list();
for (Iterator iter = honeys.iterator(); iter.hasNext();) {
Honey element = (Honey) iter.next();
logger.debug("{}", element);
}
tx.commit();
} catch (RuntimeException e) {
if (tx != null && tx.isActive()) {
try {
// Second try catch as the rollback could fail as well
tx.rollback();
} catch (HibernateException e1) {
logger.debug("Error rolling back transaction");
}
// throw again the first exception
throw e;
}


}
}

private static void deleteHoney(Honey honey) {
Transaction tx = null;
Session session = SessionFactoryUtil.getInstance().getCurrentSession();
try {
tx = session.beginTransaction();
session.delete(honey);
tx.commit();
} catch (RuntimeException e) {
if (tx != null && tx.isActive()) {
try {
// Second try catch as the rollback could fail as well
tx.rollback();
} catch (HibernateException e1) {
logger.debug("Error rolling back transaction");
}
// throw again the first exception
throw e;
}
}
}

private static void createHoney(Honey honey) {
Transaction tx = null;
Session session = SessionFactoryUtil.getInstance().getCurrentSession();
try {
tx = session.beginTransaction();
session.save(honey);
tx.commit();
} catch (RuntimeException e) {
if (tx != null && tx.isActive()) {
try {
// Second try catch as the rollback could fail as well
tx.rollback();
} catch (HibernateException e1) {
logger.debug("Error rolling back transaction");
}
// throw again the first exception
throw e;
}
}
}

private static void updateHoney(Honey honey) {
Transaction tx = null;
Session session = SessionFactoryUtil.getInstance().getCurrentSession();
try {
tx = session.beginTransaction();
session.update(honey);
tx.commit();
} catch (RuntimeException e) {
if (tx != null && tx.isActive()) {
try {
// Second try catch as the rollback could fail as well
tx.rollback();
} catch (HibernateException e1) {
logger.debug("Error rolling back transaction");
}
// throw again the first exception
throw e;
}
}
}
}