hibernate example

package com.base; import java.io.Serializable; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import org.hibernate.Criteria; import org.hibernate.HibernateException; import org.hibernate.Query; import org.hibernate.Session; import org.hibernate.Transaction; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.hibernate.criterion.Expression; import org.hibernate.criterion.Order; public abstract class _BaseRootDAO { public _BaseRootDAO () {} public _BaseRootDAO (Session session) { setSession(session); } protected static Map<String, SessionFactory> sessionFactoryMap; protected SessionFactory sessionFactory; protected Session session; protected final static ThreadLocal<Session> currentSession = new ThreadLocal<Session>(); /** * Return a new Session object that must be closed when the work has been completed. * @return the active Session */ public Session getSession() { return getSession( getConfigurationFileName()); } /** * Return a new Session object that must be closed when the work has been completed. * @param configFile the config file must match the meta attribute "config-file" in the hibernate mapping file * @return the active Session */ protected Session getSession(String configFile) { if (null != session && session.isOpen()) return session; else if (null != sessionFactory) { Session s = currentSession.get(); if (null == s || !s.isOpen()) { s = sessionFactory.openSession(); currentSession.set(s); } return s; } else { Session s = currentSession.get(); if (null == s || !s.isOpen()) { s = getSessionFactory(configFile).openSession(); currentSession.set(s); } return s; } } public void setSession (Session session) { this.session = session; } /** * Configure the session factory by reading hibernate config file */ public static void initialize () { com.dao._RootDAO.initialize( (String) null); } /** * Configure the session factory by reading hibernate config file * @param configFileName the name of the configuration file */ public static void initialize (String configFileName) { com.dao._RootDAO.initialize( configFileName, com.dao._RootDAO.getNewConfiguration( null)); } public static void initialize (String configFileName, Configuration configuration) { if (null != sessionFactoryMap && null != sessionFactoryMap.get(configFileName)) return; else { if (null == configFileName) { configuration.configure(); com.dao._RootDAO.setSessionFactory( null, configuration.buildSessionFactory()); } else { configuration.configure( configFileName); com.dao._RootDAO.setSessionFactory( configFileName, configuration.buildSessionFactory()); } } } /** * Set the session factory */ public void setSessionFactory (SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } /** * Set the session factory */ protected static void setSessionFactory (String configFileName, SessionFactory sf) { if (null == configFileName) configFileName = ""; if (null == sessionFactoryMap) sessionFactoryMap = new HashMap<String, SessionFactory>(); sessionFactoryMap.put( configFileName, sf); } /** * Return the SessionFactory that is to be used by these DAOs. Change this * and implement your own strategy if you, for example, want to pull the SessionFactory * from the JNDI tree. */ public SessionFactory getSessionFactory() { if (null != sessionFactory) return sessionFactory; else return getSessionFactory( getConfigurationFileName()); } public SessionFactory getSessionFactory(String configFileName) { if (null == configFileName) configFileName = ""; if (null == sessionFactoryMap) initialize(configFileName); SessionFactory sf = (SessionFactory) sessionFactoryMap.get(configFileName); if (null == sf) throw new RuntimeException("The session factory for '" + configFileName + "' has not been initialized (or an error occured during initialization)"); else return sf; } /** * Close all sessions for the current thread */ public static void closeCurrentSession () { Session s = currentSession.get(); if (null != s) { if (s.isOpen()) s.close(); currentSession.set(null); } } /** * Close the session */ public void closeSession (Session session) { if (null != session) session.close(); } /** * Begin the transaction related to the session */ public Transaction beginTransaction(Session s) { return s.beginTransaction(); } /** * Commit the given transaction */ public void commitTransaction(Transaction t) { t.commit(); } /** * Return a new Configuration to use. This is not a mistake and is meant * to be overridden in the RootDAO if you want to do something different. * The file name is passed in so you have that to access. The config file * is read in the initialize method. */ public static Configuration getNewConfiguration (String configFileName) { return new Configuration(); } /** * Return the name of the configuration file to be used with this DAO or null if default */ public String getConfigurationFileName () { return null; } /** * Return the specific Object class that will be used for class-specific * implementation of this DAO. * @return the reference Class */ protected abstract Class getReferenceClass(); /** * Used by the base DAO classes but here for your modification * Get object matching the given key and return it. */ protected Object get(Class refClass, Serializable key) { Session s = null; try { s = getSession(); return get(refClass, key, s); } finally { closeSession(s); } } /** * Used by the base DAO classes but here for your modification * Get object matching the given key and return it. */ protected Object get(Class refClass, Serializable key, Session s) { return s.get(refClass, key); } /** * Used by the base DAO classes but here for your modification * Load object matching the given key and return it. */ protected Object load(Class refClass, Serializable key) { Session s = null; try { s = getSession(); return load(refClass, key, s); } finally { closeSession(s); } } /** * Used by the base DAO classes but here for your modification * Load object matching the given key and return it. */ protected Object load(Class refClass, Serializable key, Session s) { return s.load(refClass, key); } /** * Return all objects related to the implementation of this DAO with no filter. */ public java.util.List findAll () { Session s = null; try { s = getSession(); return findAll(s); } finally { closeSession(s); } } /** * Return all objects related to the implementation of this DAO with no filter. * Use the session given. * @param s the Session */ public java.util.List findAll (Session s) { return findAll(s, getDefaultOrder()); } /** * Return all objects related to the implementation of this DAO with no filter. */ public java.util.List findAll (Order defaultOrder) { Session s = null; try { s = getSession(); return findAll(s, defaultOrder); } finally { closeSession(s); } } /** * Return all objects related to the implementation of this DAO with no filter. * Use the session given. * @param s the Session */ public java.util.List findAll (Session s, Order defaultOrder) { Criteria crit = s.createCriteria(getReferenceClass()); if (null != defaultOrder) crit.addOrder(defaultOrder); return crit.list(); } /** * Return all obj