//$Id: SessionImpl.java 10689 2006-11-02 18:53:54Z [email protected] $
package org.hibernate.impl;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.sql.Connection;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.dom4j.Element;
import org.hibernate.CacheMode;
import org.hibernate.ConnectionReleaseMode;
import org.hibernate.Criteria;
import org.hibernate.EntityMode;
import org.hibernate.Filter;
import org.hibernate.FlushMode;
import org.hibernate.HibernateException;
import org.hibernate.Interceptor;
import org.hibernate.LockMode;
import org.hibernate.MappingException;
import org.hibernate.ObjectDeletedException;
import org.hibernate.Query;
import org.hibernate.QueryException;
import org.hibernate.ReplicationMode;
import org.hibernate.SQLQuery;
import org.hibernate.ScrollMode;
import org.hibernate.ScrollableResults;
import org.hibernate.Session;
import org.hibernate.SessionException;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.TransientObjectException;
import org.hibernate.UnresolvableObjectException;
import org.hibernate.engine.query.sql.NativeSQLQuerySpecification;
import org.hibernate.collection.PersistentCollection;
import org.hibernate.engine.ActionQueue;
import org.hibernate.engine.CollectionEntry;
import org.hibernate.engine.EntityEntry;
import org.hibernate.engine.EntityKey;
import org.hibernate.engine.FilterDefinition;
import org.hibernate.engine.PersistenceContext;
import org.hibernate.engine.QueryParameters;
import org.hibernate.engine.StatefulPersistenceContext;
import org.hibernate.engine.Status;
import org.hibernate.engine.query.FilterQueryPlan;
import org.hibernate.engine.query.HQLQueryPlan;
import org.hibernate.engine.query.NativeSQLQueryPlan;
import org.hibernate.event.AutoFlushEvent;
import org.hibernate.event.AutoFlushEventListener;
import org.hibernate.event.DeleteEvent;
import org.hibernate.event.DeleteEventListener;
import org.hibernate.event.DirtyCheckEvent;
import org.hibernate.event.DirtyCheckEventListener;
import org.hibernate.event.EventListeners;
import org.hibernate.event.EventSource;
import org.hibernate.event.EvictEvent;
import org.hibernate.event.EvictEventListener;
import org.hibernate.event.FlushEvent;
import org.hibernate.event.FlushEventListener;
import org.hibernate.event.InitializeCollectionEvent;
import org.hibernate.event.InitializeCollectionEventListener;
import org.hibernate.event.LoadEvent;
import org.hibernate.event.LoadEventListener;
import org.hibernate.event.LockEvent;
import org.hibernate.event.LockEventListener;
import org.hibernate.event.MergeEvent;
import org.hibernate.event.MergeEventListener;
import org.hibernate.event.PersistEvent;
import org.hibernate.event.PersistEventListener;
import org.hibernate.event.RefreshEvent;
import org.hibernate.event.RefreshEventListener;
import org.hibernate.event.ReplicateEvent;
import org.hibernate.event.ReplicateEventListener;
import org.hibernate.event.SaveOrUpdateEvent;
import org.hibernate.event.SaveOrUpdateEventListener;
import org.hibernate.event.LoadEventListener.LoadType;
import org.hibernate.jdbc.Batcher;
import org.hibernate.jdbc.JDBCContext;
import org.hibernate.loader.criteria.CriteriaLoader;
import org.hibernate.loader.custom.CustomLoader;
import org.hibernate.loader.custom.CustomQuery;
import org.hibernate.persister.collection.CollectionPersister;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.persister.entity.OuterJoinLoadable;
import org.hibernate.pretty.MessageHelper;
import org.hibernate.proxy.HibernateProxy;
import org.hibernate.proxy.LazyInitializer;
import org.hibernate.stat.SessionStatistics;
import org.hibernate.stat.SessionStatisticsImpl;
import org.hibernate.tuple.DynamicMapInstantiator;
import org.hibernate.type.Type;
import org.hibernate.util.ArrayHelper;
import org.hibernate.util.CollectionHelper;
import org.hibernate.util.StringHelper;


/**
 * Concrete implementation of a Session, and also the central, organizing component
 * of Hibernate's internal implementation. As such, this class exposes two interfaces;
 * Session itself, to the application, and SessionImplementor, to other components
 * of Hibernate. This class is not threadsafe.
 *
 * @author Gavin King
 */
public final class SessionImpl extends AbstractSessionImpl 
		implements EventSource, org.hibernate.classic.Session, JDBCContext.Context {

	// todo : need to find a clean way to handle the "event source" role
	// a seperate classs responsible for generating/dispatching events just duplicates most of the Session methods...
	// passing around seperate reto interceptor, factory, actionQueue, and persistentContext is not manageable...

	private static final Log log = LogFactory.getLog(SessionImpl.class);

	private transient EntityMode entityMode = EntityMode.POJO;
	private transient boolean autoClear; //for EJB3
	
	private transient long timestamp;
	private transient FlushMode flushMode = FlushMode.AUTO;
	private transient CacheMode cacheMode = CacheMode.NORMAL;

	private transient Interceptor interceptor;

	private transient int dontFlushFromFind = 0;

	private transient ActionQueue actionQueue;
	private transient StatefulPersistenceContext persistenceContext;
	private transient JDBCContext jdbcContext;
	private transient EventListeners listeners;

	private transient boolean flushBeforeCompletionEnabled;
	private transient boolean autoCloseSessionEnabled;
	private transient ConnectionReleaseMode connectionReleaseMode;
	
	private transient String fetchProfile;

	private transient Map enabledFilters = new HashMap();

	private transient Session rootSession;
	private transient Map childSessionsByEntityMode;

	/**
	 * Constructor used in building "child sessions".
	 *
	 * @param parent The parent session
	 * @param entityMode
	 */
	private SessionImpl(SessionImpl parent, EntityMode entityMode) {
		super( parent.factory );
		this.rootSession = parent;
		this.timestamp = parent.timestamp;
		this.jdbcContext = parent.jdbcContext;
		this.interceptor = parent.interceptor;
		this.listeners = parent.listeners;
		this.actionQueue = new ActionQueue( this );
		this.entityMode = entityMode;
		this.persistenceContext = new StatefulPersistenceContext( this );
		this.flushBeforeCompletionEnabled = false;
		this.autoCloseSessionEnabled = false;
		this.connectionReleaseMode = null;

		if ( factory.getStatistics().isStatisticsEnabled() ) {
			factory.getStatisticsImplementor().openSession();
		}

		log.debug( "opened session [" + entityMode + "]" );
	}

	/**
	 * Constructor used for openSession(...) processing, as well as construction
	 * of sessions for getCurrentSession().
	 *
	 * @param connection The user-supplied connection to use for this session.
	 * @param factory The factory from which this session was obtained
	 * @param autoclose NOT USED
	 * @param timestamp The timestamp for this session
	 * @param interceptor The interceptor to be applied to this session
	 * @param entityMode The entity-mode for this session
	 * @param flushBeforeCompletionEnabled Should we auto flush before completion of transaction
	 * @param autoCloseSessionEnabled Should we auto close after completion of transaction
	 * @param connectionReleaseMode The mode by which we should release JDBC connections.
	 */
	SessionImpl(
			final Connection connection,
			final SessionFactoryImpl factory,
			final boolean autoclose,
			final long timestamp,
			final Interceptor interceptor,
			final EntityMode entityMode,
			final boolean flushBeforeCompletionEnabled,
			final boolean autoCloseSessionEnabled,
			final ConnectionReleaseMode connectionReleaseMode) {
		super( factory );
		this.rootSession = null;
		this.timestamp = timestamp;
		this.entityMode = entityMode;
		this.interceptor = interceptor;
		this.listeners = factory.getEventListeners();
		this.actionQueue = new ActionQueue( this );
		this.persistenceContext = new StatefulPersistenceContext( this );
		this.flushBeforeCompletionEnabled = flushBeforeCompletionEnabled;
		this.autoCloseSessionEnabled = autoCloseSessionEnabled;
		this.connectionReleaseMode = connectionReleaseMode;
		this.jdbcContext = new JDBCContext( this, connection, interceptor );

		if ( factory.getStatistics().isStatisticsEnabled() ) {
			factory.getStatisticsImplementor().openSession();
		}

		if ( log.isDebugEnabled() ) {
			log.debug( "opened session at timestamp: " + timestamp );
		}
	}

	public Session getSession(EntityMode entityMode) {
		if ( this.entityMode == entityMode ) {
			return this;
		}

		if ( rootSession != null ) {
			rootSession.getSession( entityMode );
		}

		errorIfClosed();
		checkTransactionSynchStatus();

		SessionImpl rtn = null;
		if ( childSessionsByEntityMode == null ) {
			childSessionsByEntityMode = new HashMap();
		}
		else {
			rtn = (SessionImpl) childSessionsByEntityMode.get( entityMode );
		}

		if ( rtn == null ) {
			rtn = new SessionImpl( this, entityMode );
			childSessionsByEntityMode.put( entityMode, rtn );
		}

		return rtn;
	}

	public void clear() {
		errorIfClosed();
		checkTransactionSynchStatus();
		persistenceContext.clear();
		actionQueue.clear();
	}

	public Batcher getBatcher() {
		errorIfClosed();
		checkTransactionSynchStatus();
		// TODO : should remove this exposure
		//  and have all references to the session's batcher use the ConnectionManager.
		return jdbcContext.getConnectionManager().getBatcher();
	}

	public long getTimestamp() {
		checkTransactionSynchStatus();
		return timestamp;
	}

	public Connection close() throws HibernateException {
		log.trace( "closing session" );
		if ( isClosed() ) {
			throw new SessionException( "Session was already closed" );
		}
		

		if ( factory.getStatistics().isStatisticsEnabled() ) {
			factory.getStatisticsImplementor().closeSession();
		}

		try {
			try {
				if ( childSessionsByEntityMode != null ) {
					Iterator childSessions = childSessionsByEntityMode.values().iterator();
					while ( childSessions.hasNext() ) {
						final SessionImpl child = ( SessionImpl ) childSessions.next();
						child.close();
					}
				}
			}
			catch( Throwable t ) {
				// just ignore
			}

			if ( rootSession == null ) {
				return jdbcContext.getConnectionManager().close();
			}
			else {
				return null;
			}
		}
		finally {
			setClosed();
			cleanup();
		}
	}

	public ConnectionReleaseMode getConnectionReleaseMode() {
		checkTransactionSynchStatus();
		return connectionReleaseMode;
	}

	public boolean isAutoCloseSessionEnabled() {
		return autoCloseSessionEnabled;
	}

	public boolean isOpen() {
		checkTransactionSynchStatus();
		return !isClosed();
	}

	public boolean isFlushModeNever() {
		return FlushMode.isManualFlushMode( getFlushMode() );
	}

	public boolean isFlushBeforeCompletionEnabled() {
		return flushBeforeCompletionEnabled;
	}

	public void managedFlush() {
		if ( isClosed() ) {
			log.trace( "skipping auto-flush due to session closed" );
			return;
		}
		log.trace("automatically flushing session");
		flush();
		
		if ( childSessionsByEntityMode != null ) {
			Iterator iter = childSessionsByEntityMode.values().iterator();
			while ( iter.hasNext() ) {
				( (Session) iter.next() ).flush();
			}
		}
	}

	public boolean shouldAutoClose() {
		return isAutoCloseSessionEnabled() && !isClosed();
	}

	public void managedClose() {
		log.trace( "automatically closing session" );
		close();
	}

	public Connection connection() throws HibernateException {
		errorIfClosed();
		return jdbcContext.borrowConnection();
	}

	public boolean isConnected() {
		checkTransactionSynchStatus();
		return !isClosed() && jdbcContext.getConnectionManager().isCurrentlyConnected();
	}
	
	public boolean isTransactionInProgress() {
		checkTransactionSynchStatus();
		return !isClosed() && jdbcContext.isTransactionInProgress();
	}

	public Connection disconnect() throws HibernateException {
		errorIfClosed();
		log.debug( "disconnecting session" );
		return jdbcContext.getConnectionManager().manualDisconnect();
	}

	public void reconnect() throws HibernateException {
		errorIfClosed();
		log.debug( "reconnecting session" );
		checkTransactionSynchStatus();
		jdbcContext.getConnectionManager().manualReconnect();
	}

	public void reconnect(Connection conn) throws HibernateException {
		errorIfClosed();
		log.debug( "reconnecting session" );
		checkTransactionSynchStatus();
		jdbcContext.getConnectionManager().manualReconnect( conn );
	}

	public void beforeTransactionCompletion(Transaction tx) {
		log.trace( "before transaction completion" );
		if ( rootSession == null ) {
			try {
				interceptor.beforeTransactionCompletion(tx);
			}
			catch (Throwable t) {
				log.error("exception in interceptor beforeTransactionCompletion()", t);
			}
		}
	}
	
	public void setAutoClear(boolean enabled) {
		errorIfClosed();
		autoClear = enabled;
	}
	
	/**
	 * Check if there is a Hibernate or JTA transaction in progress and, 
	 * if there is not, flush if necessary, make sure the connection has 
	 * been committed (if it is not in autocommit mode) and run the after 
	 * completion processing
	 */
	public void afterOperation(boolean success) {
		if ( !jdbcContext.isTransactionInProgress() ) {
			jdbcContext.afterNontransactionalQuery( success );
		}
	}

	public void afterTransactionCompletion(boolean success, Transaction tx) {
		log.trace( "after transaction completion" );
		persistenceContext.afterTransactionCompletion();
		actionQueue.afterTransactionCompletion(success);
		if ( rootSession == null && tx != null ) {
			try {
				interceptor.afterTransactionCompletion(tx);
			}
			catch (Throwable t) {
				log.error("exception in interceptor afterTransactionCompletion()", t);
			}
		}
		if ( autoClear ) {
			clear();
		}
	}

	/**
	 * clear all the internal collections, just 
	 * to help the garbage collector, does not
	 * clear anything that is needed during the
	 * afterTransactionCompletion() phase
	 */
	private void cleanup() {
		persistenceContext.clear();
	}

	public LockMode getCurrentLockMode(Object object) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( object == null ) {
			throw new NullPointerException( "null object passed to getCurrentLockMode()" );
		}
		if ( object instanceof HibernateProxy ) {
			object = ( (HibernateProxy) object ).getHibernateLazyInitializer().getImplementation(this);
			if ( object == null ) {
				return LockMode.NONE;
			}
		}
		EntityEntry e = persistenceContext.getEntry(object);
		if ( e == null ) {
			throw new TransientObjectException( "Given object not associated with the session" );
		}
		if ( e.getStatus() != Status.MANAGED ) {
			throw new ObjectDeletedException( 
					"The given object was deleted", 
					e.getId(), 
					e.getPersister().getEntityName() 
				);
		}
		return e.getLockMode();
	}

	public Object getEntityUsingInterceptor(EntityKey key) throws HibernateException {
		errorIfClosed();
		// todo : should this get moved to PersistentContext?
		// logically, is PersistentContext the "thing" to which an interceptor gets attached?
		final Object result = persistenceContext.getEntity(key);
		if ( result == null ) {
			final Object newObject = interceptor.getEntity( key.getEntityName(), key.getIdentifier() );
			if ( newObject != null ) {
				lock( newObject, LockMode.NONE );
			}
			return newObject;
		}
		else {
			return result;
		}
	}


	// saveOrUpdate() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void saveOrUpdate(Object object) throws HibernateException {
		saveOrUpdate(null, object);
	}

	public void saveOrUpdate(String entityName, Object obj) throws HibernateException {
		fireSaveOrUpdate( new SaveOrUpdateEvent(entityName, obj, this) );
	}

	private void fireSaveOrUpdate(SaveOrUpdateEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		SaveOrUpdateEventListener[] saveOrUpdateEventListener = listeners.getSaveOrUpdateEventListeners();
		for ( int i = 0; i < saveOrUpdateEventListener.length; i++ ) {
			saveOrUpdateEventListener[i].onSaveOrUpdate(event);
		}
	}


	// save() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void save(Object obj, Serializable id) throws HibernateException {
		save(null, obj, id);
	}

	public Serializable save(Object obj) throws HibernateException {
		return save(null, obj);
	}

	public Serializable save(String entityName, Object object) throws HibernateException {
		return fireSave( new SaveOrUpdateEvent(entityName, object, this) );
	}

	public void save(String entityName, Object object, Serializable id) throws HibernateException {
		fireSave( new SaveOrUpdateEvent(entityName, object, id, this) );
	}

	private Serializable fireSave(SaveOrUpdateEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		SaveOrUpdateEventListener[] saveEventListener = listeners.getSaveEventListeners();
		for ( int i = 0; i < saveEventListener.length; i++ ) {
			saveEventListener[i].onSaveOrUpdate(event);
		}
		return event.getResultId();
	}


	// update() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void update(Object obj) throws HibernateException {
		update(null, obj);
	}

	public void update(Object obj, Serializable id) throws HibernateException {
		update(null, obj, id);
	}

	public void update(String entityName, Object object) throws HibernateException {
		fireUpdate( new SaveOrUpdateEvent(entityName, object, this) );
	}

	public void update(String entityName, Object object, Serializable id) throws HibernateException {
		fireUpdate(new SaveOrUpdateEvent(entityName, object, id, this));
	}

	private void fireUpdate(SaveOrUpdateEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		SaveOrUpdateEventListener[] updateEventListener = listeners.getUpdateEventListeners();
		for ( int i = 0; i < updateEventListener.length; i++ ) {
			updateEventListener[i].onSaveOrUpdate(event);
		}
	}


	// lock() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void lock(String entityName, Object object, LockMode lockMode) throws HibernateException {
		fireLock( new LockEvent(entityName, object, lockMode, this) );
	}

	public void lock(Object object, LockMode lockMode) throws HibernateException {
		fireLock( new LockEvent(object, lockMode, this) );
	}

	private void fireLock(LockEvent lockEvent) {
		errorIfClosed();
		checkTransactionSynchStatus();
		LockEventListener[] lockEventListener = listeners.getLockEventListeners();
		for ( int i = 0; i < lockEventListener.length; i++ ) {
			lockEventListener[i].onLock( lockEvent );
		}
	}


	// persist() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void persist(String entityName, Object object) throws HibernateException {
		firePersist( new PersistEvent(entityName, object, this) );
	}

	public void persist(Object object) throws HibernateException {
		persist(null, object);
	}

	public void persist(String entityName, Object object, Map copiedAlready)
	throws HibernateException {
		firePersist( copiedAlready, new PersistEvent(entityName, object, this) );
	}

	private void firePersist(Map copiedAlready, PersistEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		PersistEventListener[] persistEventListener = listeners.getPersistEventListeners();
		for ( int i = 0; i < persistEventListener.length; i++ ) {
			persistEventListener[i].onPersist(event, copiedAlready);
		}
	}

	private void firePersist(PersistEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		PersistEventListener[] createEventListener = listeners.getPersistEventListeners();
		for ( int i = 0; i < createEventListener.length; i++ ) {
			createEventListener[i].onPersist(event);
		}
	}


	// persistOnFlush() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void persistOnFlush(String entityName, Object object)
			throws HibernateException {
		firePersistOnFlush( new PersistEvent(entityName, object, this) );
	}

	public void persistOnFlush(Object object) throws HibernateException {
		persist(null, object);
	}

	public void persistOnFlush(String entityName, Object object, Map copiedAlready)
			throws HibernateException {
		firePersistOnFlush( copiedAlready, new PersistEvent(entityName, object, this) );
	}

	private void firePersistOnFlush(Map copiedAlready, PersistEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		PersistEventListener[] persistEventListener = listeners.getPersistOnFlushEventListeners();
		for ( int i = 0; i < persistEventListener.length; i++ ) {
			persistEventListener[i].onPersist(event, copiedAlready);
		}
	}

	private void firePersistOnFlush(PersistEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		PersistEventListener[] createEventListener = listeners.getPersistOnFlushEventListeners();
		for ( int i = 0; i < createEventListener.length; i++ ) {
			createEventListener[i].onPersist(event);
		}
	}


	// merge() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public Object merge(String entityName, Object object) throws HibernateException {
		return fireMerge( new MergeEvent(entityName, object, this) );
	}

	public Object merge(Object object) throws HibernateException {
		return merge(null, object);
	}

	public void merge(String entityName, Object object, Map copiedAlready) throws HibernateException {
		fireMerge( copiedAlready, new MergeEvent(entityName, object, this) );
	}

	private Object fireMerge(MergeEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		MergeEventListener[] mergeEventListener = listeners.getMergeEventListeners();
		for ( int i = 0; i < mergeEventListener.length; i++ ) {
			mergeEventListener[i].onMerge(event);
		}
		return event.getResult();
	}

	private void fireMerge(Map copiedAlready, MergeEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		MergeEventListener[] mergeEventListener = listeners.getMergeEventListeners();
		for ( int i = 0; i < mergeEventListener.length; i++ ) {
			mergeEventListener[i].onMerge(event, copiedAlready);
		}
	}


	// saveOrUpdateCopy() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public Object saveOrUpdateCopy(String entityName, Object object)
			throws HibernateException {
		return fireSaveOrUpdateCopy( new MergeEvent(entityName, object, this) );
	}

	public Object saveOrUpdateCopy(Object object) throws HibernateException {
		return saveOrUpdateCopy( null, object );
	}

	public Object saveOrUpdateCopy(String entityName, Object object, Serializable id)
			throws HibernateException {
		return fireSaveOrUpdateCopy( new MergeEvent(entityName, object, id, this) );
	}

	public Object saveOrUpdateCopy(Object object, Serializable id)
			throws HibernateException {
		return saveOrUpdateCopy( null, object, id );
	}

	public void saveOrUpdateCopy(String entityName, Object object, Map copiedAlready)
			throws HibernateException {
		fireSaveOrUpdateCopy( copiedAlready, new MergeEvent( entityName, object, this ) );
	}

	private void fireSaveOrUpdateCopy(Map copiedAlready, MergeEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		MergeEventListener[] saveOrUpdateCopyEventListener = listeners.getSaveOrUpdateCopyEventListeners();
		for ( int i = 0; i < saveOrUpdateCopyEventListener.length; i++ ) {
			saveOrUpdateCopyEventListener[i].onMerge(event, copiedAlready);
		}
	}

	private Object fireSaveOrUpdateCopy(MergeEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		MergeEventListener[] saveOrUpdateCopyEventListener = listeners.getSaveOrUpdateCopyEventListeners();
		for ( int i = 0; i < saveOrUpdateCopyEventListener.length; i++ ) {
			saveOrUpdateCopyEventListener[i].onMerge(event);
		}
		return event.getResult();
	}


	// delete() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	/**
	 * Delete a persistent object
	 */
	public void delete(Object object) throws HibernateException {
		fireDelete( new DeleteEvent(object, this) );
	}

	/**
	 * Delete a persistent object (by explicit entity name)
	 */
	public void delete(String entityName, Object object) throws HibernateException {
		fireDelete( new DeleteEvent( entityName, object, this ) );
	}

	/**
	 * Delete a persistent object
	 */
	public void delete(String entityName, Object object, boolean isCascadeDeleteEnabled, Set transientEntities) throws HibernateException {
		fireDelete( new DeleteEvent( entityName, object, isCascadeDeleteEnabled, this ), transientEntities );
	}

	private void fireDelete(DeleteEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		DeleteEventListener[] deleteEventListener = listeners.getDeleteEventListeners();
		for ( int i = 0; i < deleteEventListener.length; i++ ) {
			deleteEventListener[i].onDelete( event );
		}
	}

	private void fireDelete(DeleteEvent event, Set transientEntities) {
		errorIfClosed();
		checkTransactionSynchStatus();
		DeleteEventListener[] deleteEventListener = listeners.getDeleteEventListeners();
		for ( int i = 0; i < deleteEventListener.length; i++ ) {
			deleteEventListener[i].onDelete( event, transientEntities );
		}
	}


	// load()/get() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void load(Object object, Serializable id) throws HibernateException {
		LoadEvent event = new LoadEvent(id, object, this);
		fireLoad( event, LoadEventListener.RELOAD );
	}

	public Object load(Class entityClass, Serializable id) throws HibernateException {
		return load( entityClass.getName(), id );
	}

	public Object load(String entityName, Serializable id) throws HibernateException {
		LoadEvent event = new LoadEvent(id, entityName, false, this);
		boolean success = false;
		try {
			fireLoad( event, LoadEventListener.LOAD );
			if ( event.getResult() == null ) {
				getFactory().getEntityNotFoundDelegate().handleEntityNotFound( entityName, id );
			}
			success = true;
			return event.getResult();
		}
		finally {
			afterOperation(success);
		}
	}

	public Object get(Class entityClass, Serializable id) throws HibernateException {
		return get( entityClass.getName(), id );
	}

	public Object get(String entityName, Serializable id) throws HibernateException {
		LoadEvent event = new LoadEvent(id, entityName, false, this);
		boolean success = false;
		try {
			fireLoad(event, LoadEventListener.GET);
			success = true;
			return event.getResult();
		}
		finally {
			afterOperation(success);
		}
	}

	/**
	 * Load the data for the object with the specified id into a newly created object.
	 * This is only called when lazily initializing a proxy.
	 * Do NOT return a proxy.
	 */
	public Object immediateLoad(String entityName, Serializable id) throws HibernateException {
		if ( log.isDebugEnabled() ) {
			EntityPersister persister = getFactory().getEntityPersister(entityName);
			log.debug( "initializing proxy: " + MessageHelper.infoString( persister, id, getFactory() ) );
		}
		
		LoadEvent event = new LoadEvent(id, entityName, true, this);
		fireLoad(event, LoadEventListener.IMMEDIATE_LOAD);
		return event.getResult();
	}

	public Object internalLoad(String entityName, Serializable id, boolean eager, boolean nullable) throws HibernateException {
		// todo : remove
		LoadEventListener.LoadType type = nullable ? 
				LoadEventListener.INTERNAL_LOAD_NULLABLE : 
				eager ? LoadEventListener.INTERNAL_LOAD_EAGER : LoadEventListener.INTERNAL_LOAD_LAZY;
		LoadEvent event = new LoadEvent(id, entityName, true, this);
		fireLoad(event, type);
		if ( !nullable ) {
			UnresolvableObjectException.throwIfNull( event.getResult(), id, entityName );
		}
		return event.getResult();
	}

	public Object load(Class entityClass, Serializable id, LockMode lockMode) throws HibernateException {
		return load( entityClass.getName(), id, lockMode );
	}

	public Object load(String entityName, Serializable id, LockMode lockMode) throws HibernateException {
		LoadEvent event = new LoadEvent(id, entityName, lockMode, this);
		fireLoad( event, LoadEventListener.LOAD );
		return event.getResult();
	}

	public Object get(Class entityClass, Serializable id, LockMode lockMode) throws HibernateException {
		return get( entityClass.getName(), id, lockMode );
	}

	public Object get(String entityName, Serializable id, LockMode lockMode) throws HibernateException {
		LoadEvent event = new LoadEvent(id, entityName, lockMode, this);
	   	fireLoad(event, LoadEventListener.GET);
		return event.getResult();
	}

	private void fireLoad(LoadEvent event, LoadType loadType) {
		errorIfClosed();
		checkTransactionSynchStatus();
		LoadEventListener[] loadEventListener = listeners.getLoadEventListeners();
		for ( int i = 0; i < loadEventListener.length; i++ ) {
			loadEventListener[i].onLoad(event, loadType);
		}
	}


	// refresh() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void refresh(Object object) throws HibernateException {
		fireRefresh( new RefreshEvent(object, this) );
	}

	public void refresh(Object object, LockMode lockMode) throws HibernateException {
		fireRefresh( new RefreshEvent(object, lockMode, this) );
	}

	public void refresh(Object object, Map refreshedAlready) throws HibernateException {
		fireRefresh( refreshedAlready, new RefreshEvent(object, this) );
	}

	private void fireRefresh(RefreshEvent refreshEvent) {
		errorIfClosed();
		checkTransactionSynchStatus();
		RefreshEventListener[] refreshEventListener = listeners.getRefreshEventListeners();
		for ( int i = 0; i < refreshEventListener.length; i++ ) {
			refreshEventListener[i].onRefresh( refreshEvent );
		}
	}

	private void fireRefresh(Map refreshedAlready, RefreshEvent refreshEvent) {
		errorIfClosed();
		checkTransactionSynchStatus();
		RefreshEventListener[] refreshEventListener = listeners.getRefreshEventListeners();
		for ( int i = 0; i < refreshEventListener.length; i++ ) {
			refreshEventListener[i].onRefresh( refreshEvent, refreshedAlready );
		}
	}


	// replicate() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	public void replicate(Object obj, ReplicationMode replicationMode) throws HibernateException {
		fireReplicate( new ReplicateEvent(obj, replicationMode, this) );
	}

	public void replicate(String entityName, Object obj, ReplicationMode replicationMode)
	throws HibernateException {
		fireReplicate( new ReplicateEvent(entityName, obj, replicationMode, this) );
	}

	private void fireReplicate(ReplicateEvent event) {
		errorIfClosed();
		checkTransactionSynchStatus();
		ReplicateEventListener[] replicateEventListener = listeners.getReplicateEventListeners();
		for ( int i = 0; i < replicateEventListener.length; i++ ) {
			replicateEventListener[i].onReplicate(event);
		}
	}


	// evict() operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	/**
	 * remove any hard references to the entity that are held by the infrastructure
	 * (references held by application or other persistant instances are okay)
	 */
	public void evict(Object object) throws HibernateException {
		fireEvict( new EvictEvent(object, this) );
	}

	private void fireEvict(EvictEvent evictEvent) {
		errorIfClosed();
		checkTransactionSynchStatus();
		EvictEventListener[] evictEventListener = listeners.getEvictEventListeners();
		for ( int i = 0; i < evictEventListener.length; i++ ) {
			evictEventListener[i].onEvict( evictEvent );
		}
	}

	/**
	 * detect in-memory changes, determine if the changes are to tables
	 * named in the query and, if so, complete execution the flush
	 */
	protected boolean autoFlushIfRequired(Set querySpaces) throws HibernateException {
		errorIfClosed();
		if ( ! isTransactionInProgress() ) {
			// do not auto-flush while outside a transaction
			return false;
		}
		AutoFlushEvent event = new AutoFlushEvent(querySpaces, this);
		AutoFlushEventListener[] autoFlushEventListener = listeners.getAutoFlushEventListeners();
		for ( int i = 0; i < autoFlushEventListener.length; i++ ) {
			autoFlushEventListener[i].onAutoFlush(event);
		}
		return event.isFlushRequired();
	}

	public boolean isDirty() throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		log.debug("checking session dirtiness");
		if ( actionQueue.areInsertionsOrDeletionsQueued() ) {
			log.debug("session dirty (scheduled updates and insertions)");
			return true;
		}
		else {
			DirtyCheckEvent event = new DirtyCheckEvent(this);
			DirtyCheckEventListener[] dirtyCheckEventListener = listeners.getDirtyCheckEventListeners();
			for ( int i = 0; i < dirtyCheckEventListener.length; i++ ) {
				dirtyCheckEventListener[i].onDirtyCheck(event);
			}
			return event.isDirty();
		}
	}

	public void flush() throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( persistenceContext.getCascadeLevel() > 0 ) {
			throw new HibernateException("Flush during cascade is dangerous");
		}
		FlushEventListener[] flushEventListener = listeners.getFlushEventListeners();
		for ( int i = 0; i < flushEventListener.length; i++ ) {
			flushEventListener[i].onFlush( new FlushEvent(this) );
		}
	}

	public void forceFlush(EntityEntry entityEntry) throws HibernateException {
		errorIfClosed();
		if ( log.isDebugEnabled() ) {
			log.debug(
				"flushing to force deletion of re-saved object: " +
				MessageHelper.infoString( entityEntry.getPersister(), entityEntry.getId(), getFactory() )
			);
		}

		if ( persistenceContext.getCascadeLevel() > 0 ) {
			throw new ObjectDeletedException(
				"deleted object would be re-saved by cascade (remove deleted object from associations)",
				entityEntry.getId(),
				entityEntry.getPersister().getEntityName()
			);
		}

		flush();
	}

	public Filter getEnabledFilter(String filterName) {
		checkTransactionSynchStatus();
		return (Filter) enabledFilters.get(filterName);
	}

	public Filter enableFilter(String filterName) {
		errorIfClosed();
		checkTransactionSynchStatus();
		FilterImpl filter = new FilterImpl( factory.getFilterDefinition(filterName) );
		enabledFilters.put(filterName, filter);
		return filter;
	}

	public void disableFilter(String filterName) {
		errorIfClosed();
		checkTransactionSynchStatus();
		enabledFilters.remove(filterName);
	}

	public Object getFilterParameterValue(String filterParameterName) {
		errorIfClosed();
		checkTransactionSynchStatus();
		String[] parsed = parseFilterParameterName(filterParameterName);
		FilterImpl filter = (FilterImpl) enabledFilters.get( parsed[0] );
		if (filter == null) {
			throw new IllegalArgumentException("Filter [" + parsed[0] + "] currently not enabled");
		}
		return filter.getParameter( parsed[1] );
	}

	public Type getFilterParameterType(String filterParameterName) {
		errorIfClosed();
		checkTransactionSynchStatus();
		String[] parsed = parseFilterParameterName(filterParameterName);
		FilterDefinition filterDef = factory.getFilterDefinition( parsed[0] );
		if (filterDef == null) {
			throw new IllegalArgumentException("Filter [" + parsed[0] + "] not defined");
		}
		Type type = filterDef.getParameterType( parsed[1] );
		if (type == null) {
			// this is an internal error of some sort...
			throw new InternalError("Unable to locate type for filter parameter");
		}
		return type;
	}

	public Map getEnabledFilters() {
		errorIfClosed();
		checkTransactionSynchStatus();
		// First, validate all the enabled filters...
		//TODO: this implementation has bad performance
		Iterator itr = enabledFilters.values().iterator();
		while ( itr.hasNext() ) {
			final Filter filter = (Filter) itr.next();
			filter.validate();
		}
		return enabledFilters;
	}

	private String[] parseFilterParameterName(String filterParameterName) {
		int dot = filterParameterName.indexOf('.');
		if (dot <= 0) {
			throw new IllegalArgumentException("Invalid filter-parameter name format"); // TODO: what type?
		}
		String filterName = filterParameterName.substring(0, dot);
		String parameterName = filterParameterName.substring(dot+1);
		return new String[] {filterName, parameterName};
	}


	/**
	 * Retrieve a list of persistent objects using a hibernate query
	 */
	public List find(String query) throws HibernateException {
		return list( query, new QueryParameters() );
	}

	public List find(String query, Object value, Type type) throws HibernateException {
		return list( query, new QueryParameters(type, value) );
	}

	public List find(String query, Object[] values, Type[] types) throws HibernateException {
		return list( query, new QueryParameters(types, values) );
	}

	public List list(String query, QueryParameters queryParameters) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		queryParameters.validateParameters();
		HQLQueryPlan plan = getHQLQueryPlan( query, false );
		autoFlushIfRequired( plan.getQuerySpaces() );

		List results = CollectionHelper.EMPTY_LIST;
		boolean success = false;

		dontFlushFromFind++;   //stops flush being called multiple times if this method is recursively called
		try {
			results = plan.performList( queryParameters, this );
			success = true;
		}
		finally {
			dontFlushFromFind--;
			afterOperation(success);
		}
		return results;
	}

	public int executeUpdate(String query, QueryParameters queryParameters) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		queryParameters.validateParameters();
		HQLQueryPlan plan = getHQLQueryPlan( query, false );
		autoFlushIfRequired( plan.getQuerySpaces() );

		boolean success = false;
		int result = 0;
		try {
			result = plan.performExecuteUpdate( queryParameters, this );
			success = true;
		}
		finally {
			afterOperation(success);
		}
		return result;
	}

    public int executeNativeUpdate(NativeSQLQuerySpecification nativeQuerySpecification,
            QueryParameters queryParameters) throws HibernateException {
        errorIfClosed();
        checkTransactionSynchStatus();
        queryParameters.validateParameters();
        NativeSQLQueryPlan plan = getNativeSQLQueryPlan(nativeQuerySpecification);

        
        autoFlushIfRequired( plan.getCustomQuery().getQuerySpaces() );
        
        boolean success = false;
        int result = 0;
        try {
            result = plan.performExecuteUpdate(queryParameters, this);
            success = true;
        } finally {
            afterOperation(success);
        }
        return result;
    }

	public Iterator iterate(String query) throws HibernateException {
		return iterate( query, new QueryParameters() );
	}

	public Iterator iterate(String query, Object value, Type type) throws HibernateException {
		return iterate( query, new QueryParameters(type, value) );
	}

	public Iterator iterate(String query, Object[] values, Type[] types) throws HibernateException {
		return iterate( query, new QueryParameters(types, values) );
	}

	public Iterator iterate(String query, QueryParameters queryParameters) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		queryParameters.validateParameters();
		HQLQueryPlan plan = getHQLQueryPlan( query, true );
		autoFlushIfRequired( plan.getQuerySpaces() );

		dontFlushFromFind++; //stops flush being called multiple times if this method is recursively called
		try {
			return plan.performIterate( queryParameters, this );
		}
		finally {
			dontFlushFromFind--;
		}
	}

	public ScrollableResults scroll(String query, QueryParameters queryParameters) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		HQLQueryPlan plan = getHQLQueryPlan( query, false );
		autoFlushIfRequired( plan.getQuerySpaces() );
		dontFlushFromFind++;
		try {
			return plan.performScroll( queryParameters, this );
		}
		finally {
			dontFlushFromFind--;
		}
	}

	public int delete(String query) throws HibernateException {
		return delete( query, ArrayHelper.EMPTY_OBJECT_ARRAY, ArrayHelper.EMPTY_TYPE_ARRAY );
	}

	public int delete(String query, Object value, Type type) throws HibernateException {
		return delete( query, new Object[]{value}, new Type[]{type} );
	}

	public int delete(String query, Object[] values, Type[] types) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( query == null ) {
			throw new IllegalArgumentException("attempt to perform delete-by-query with null query");
		}

		if ( log.isTraceEnabled() ) {
			log.trace( "delete: " + query );
			if ( values.length != 0 ) {
				log.trace( "parameters: " + StringHelper.toString( values ) );
			}
		}

		List list = find( query, values, types );
		int deletionCount = list.size();
		for ( int i = 0; i < deletionCount; i++ ) {
			delete( list.get( i ) );
		}

		return deletionCount;
	}

	public Query createFilter(Object collection, String queryString) {
		errorIfClosed();
		checkTransactionSynchStatus();
		CollectionFilterImpl filter = new CollectionFilterImpl(
				queryString,
		        collection,
		        this,
		        getFilterQueryPlan( collection, queryString, null, false ).getParameterMetadata()
		);
		filter.setComment( queryString );
		return filter;
	}
	
	public Query getNamedQuery(String queryName) throws MappingException {
		errorIfClosed();
		checkTransactionSynchStatus();
		return super.getNamedQuery(queryName);
	}

	public Object instantiate(String entityName, Serializable id) throws HibernateException {
		return instantiate( factory.getEntityPersister(entityName), id );
	}

	/**
	 * give the interceptor an opportunity to override the default instantiation
	 */
	public Object instantiate(EntityPersister persister, Serializable id) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		Object result = interceptor.instantiate( persister.getEntityName(), entityMode, id );
		if ( result == null ) {
			result = persister.instantiate( id, entityMode );
		}
		return result;
	}

	public EntityMode getEntityMode() {
		checkTransactionSynchStatus();
		return entityMode;
	}

	public void setFlushMode(FlushMode flushMode) {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( log.isTraceEnabled() ) {
			log.trace("setting flush mode to: " + flushMode);
		}
		this.flushMode = flushMode;
	}
	
	public FlushMode getFlushMode() {
		checkTransactionSynchStatus();
		return flushMode;
	}

	public CacheMode getCacheMode() {
		checkTransactionSynchStatus();
		return cacheMode;
	}
	
	public void setCacheMode(CacheMode cacheMode) {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( log.isTraceEnabled() ) {
			log.trace("setting cache mode to: " + cacheMode);
		}
		this.cacheMode= cacheMode; 
	}

	public Transaction getTransaction() throws HibernateException {
		errorIfClosed();
		return jdbcContext.getTransaction();
	}
	
	public Transaction beginTransaction() throws HibernateException {
		errorIfClosed();
		if ( rootSession != null ) {
			// todo : should seriously consider not allowing a txn to begin from a child session
			//      can always route the request to the root session...
			log.warn( "Transaction started on non-root session" );
		}
		Transaction result = getTransaction();
		result.begin();
		return result;
	}
	
	public void afterTransactionBegin(Transaction tx) {
		errorIfClosed();
		interceptor.afterTransactionBegin(tx);
	}

	public EntityPersister getEntityPersister(final String entityName, final Object object) {
		errorIfClosed();
		if (entityName==null) {
			return factory.getEntityPersister( guessEntityName( object ) );
		}
		else {
			// try block is a hack around fact that currently tuplizers are not
			// given the opportunity to resolve a subclass entity name.  this
			// allows the (we assume custom) interceptor the ability to
			// influence this decision if we were not able to based on the
			// given entityName
			try {
				return factory.getEntityPersister( entityName )
						.getSubclassEntityPersister( object, getFactory(), entityMode );
			}
			catch( HibernateException e ) {
				try {
					return getEntityPersister( null, object );
				}
				catch( HibernateException e2 ) {
					throw e;
				}
			}
		}
	}

	// not for internal use:
	public Serializable getIdentifier(Object object) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( object instanceof HibernateProxy ) {
			LazyInitializer li = ( (HibernateProxy) object ).getHibernateLazyInitializer();
			if ( li.getSession() != this ) {
				throw new TransientObjectException( "The proxy was not associated with this session" );
			}
			return li.getIdentifier();
		}
		else {
			EntityEntry entry = persistenceContext.getEntry(object);
			if ( entry == null ) {
				throw new TransientObjectException( "The instance was not associated with this session" );
			}
			return entry.getId();
		}
	}

	/**
	 * Get the id value for an object that is actually associated with the session. This
	 * is a bit stricter than getEntityIdentifierIfNotUnsaved().
	 */
	public Serializable getContextEntityIdentifier(Object object) {
		errorIfClosed();
		if ( object instanceof HibernateProxy ) {
			return getProxyIdentifier(object);
		}
		else {
			EntityEntry entry = persistenceContext.getEntry(object);
			return entry != null ? entry.getId() : null;
		}
	}
	
	private Serializable getProxyIdentifier(Object proxy) {
		return ( (HibernateProxy) proxy ).getHibernateLazyInitializer().getIdentifier();
	}

	public Collection filter(Object collection, String filter) throws HibernateException {
		return listFilter( collection, filter, new QueryParameters( new Type[1], new Object[1] ) );
	}

	public Collection filter(Object collection, String filter, Object value, Type type) throws HibernateException {
		return listFilter( collection, filter, new QueryParameters( new Type[]{null, type}, new Object[]{null, value} ) );
	}

	public Collection filter(Object collection, String filter, Object[] values, Type[] types) 
	throws HibernateException {
		Object[] vals = new Object[values.length + 1];
		Type[] typs = new Type[types.length + 1];
		System.arraycopy( values, 0, vals, 1, values.length );
		System.arraycopy( types, 0, typs, 1, types.length );
		return listFilter( collection, filter, new QueryParameters( typs, vals ) );
	}

	private FilterQueryPlan getFilterQueryPlan(
			Object collection,
			String filter,
			QueryParameters parameters,
			boolean shallow) throws HibernateException {
		if ( collection == null ) {
			throw new NullPointerException( "null collection passed to filter" );
		}

		CollectionEntry entry = persistenceContext.getCollectionEntryOrNull( collection );
		final CollectionPersister roleBeforeFlush = (entry == null) ? null : entry.getLoadedPersister();

		FilterQueryPlan plan = null;
		if ( roleBeforeFlush == null ) {
			// if it was previously unreferenced, we need to flush in order to
			// get its state into the database in order to execute query
			flush();
			entry = persistenceContext.getCollectionEntryOrNull( collection );
			CollectionPersister roleAfterFlush = (entry == null) ? null : entry.getLoadedPersister();
			if ( roleAfterFlush == null ) {
				throw new QueryException( "The collection was unreferenced" );
			}
			plan = factory.getQueryPlanCache().getFilterQueryPlan( filter, roleAfterFlush.getRole(), shallow, getEnabledFilters() );
		}
		else {
			// otherwise, we only need to flush if there are in-memory changes
			// to the queried tables
			plan = factory.getQueryPlanCache().getFilterQueryPlan( filter, roleBeforeFlush.getRole(), shallow, getEnabledFilters() );
			if ( autoFlushIfRequired( plan.getQuerySpaces() ) ) {
				// might need to run a different filter entirely after the flush
				// because the collection role may have changed
				entry = persistenceContext.getCollectionEntryOrNull( collection );
				CollectionPersister roleAfterFlush = (entry == null) ? null : entry.getLoadedPersister();
				if ( roleBeforeFlush != roleAfterFlush ) {
					if ( roleAfterFlush == null ) {
						throw new QueryException( "The collection was dereferenced" );
					}
					plan = factory.getQueryPlanCache().getFilterQueryPlan( filter, roleAfterFlush.getRole(), shallow, getEnabledFilters() );
				}
			}
		}

		if ( parameters != null ) {
			parameters.getPositionalParameterValues()[0] = entry.getLoadedKey();
			parameters.getPositionalParameterTypes()[0] = entry.getLoadedPersister().getKeyType();
		}

		return plan;
	}

	public List listFilter(Object collection, String filter, QueryParameters queryParameters) 
	throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		FilterQueryPlan plan = getFilterQueryPlan( collection, filter, queryParameters, false );
		List results = CollectionHelper.EMPTY_LIST;

		boolean success = false;
		dontFlushFromFind++;   //stops flush being called multiple times if this method is recursively called
		try {
			results = plan.performList( queryParameters, this );
			success = true;
		}
		finally {
			dontFlushFromFind--;
			afterOperation(success);
		}
		return results;
	}

	public Iterator iterateFilter(Object collection, String filter, QueryParameters queryParameters) 
	throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		FilterQueryPlan plan = getFilterQueryPlan( collection, filter, queryParameters, true );
		return plan.performIterate( queryParameters, this );
	}

	public Criteria createCriteria(Class persistentClass, String alias) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new CriteriaImpl( persistentClass.getName(), alias, this );
	}

	public Criteria createCriteria(String entityName, String alias) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new CriteriaImpl(entityName, alias, this);
	}

	public Criteria createCriteria(Class persistentClass) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new CriteriaImpl( persistentClass.getName(), this );
	}

	public Criteria createCriteria(String entityName) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new CriteriaImpl(entityName, this);
	}

	public ScrollableResults scroll(CriteriaImpl criteria, ScrollMode scrollMode) {
		errorIfClosed();
		checkTransactionSynchStatus();
		String entityName = criteria.getEntityOrClassName();
		CriteriaLoader loader = new CriteriaLoader(
				getOuterJoinLoadable(entityName),
				factory,
				criteria,
				entityName,
				getEnabledFilters()
		);
		autoFlushIfRequired( loader.getQuerySpaces() );
		dontFlushFromFind++;
		try {
			return loader.scroll(this, scrollMode);
		}
		finally {
			dontFlushFromFind--;
		}
	}

	public List list(CriteriaImpl criteria) throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		String[] implementors = factory.getImplementors( criteria.getEntityOrClassName() );
		int size = implementors.length;

		CriteriaLoader[] loaders = new CriteriaLoader[size];
		Set spaces = new HashSet();
		for( int i=0; i <size; i++ ) {

			loaders[i] = new CriteriaLoader(
					getOuterJoinLoadable( implementors[i] ),
					factory,
					criteria,
					implementors[i],
					getEnabledFilters()
				);

			spaces.addAll( loaders[i].getQuerySpaces() );

		}

		autoFlushIfRequired(spaces);

		List results = Collections.EMPTY_LIST;
		dontFlushFromFind++;
		boolean success = false;
		try {
			for( int i=0; i<size; i++ ) {
				final List currentResults = loaders[i].list(this);
				currentResults.addAll(results);
				results = currentResults;
			}
			success = true;
		}
		finally {
			dontFlushFromFind--;
			afterOperation(success);
		}

		return results;
	}

	private OuterJoinLoadable getOuterJoinLoadable(String entityName) throws MappingException {
		EntityPersister persister = factory.getEntityPersister(entityName);
		if ( !(persister instanceof OuterJoinLoadable) ) {
			throw new MappingException( "class persister is not OuterJoinLoadable: " + entityName );
		}
		return ( OuterJoinLoadable ) persister;
	}

	public boolean contains(Object object) {
		errorIfClosed();
		checkTransactionSynchStatus();
		if ( object instanceof HibernateProxy ) {
			//do not use proxiesByKey, since not all
			//proxies that point to this session's
			//instances are in that collection!
			LazyInitializer li = ( (HibernateProxy) object ).getHibernateLazyInitializer();
			if ( li.isUninitialized() ) {
				//if it is an uninitialized proxy, pointing
				//with this session, then when it is accessed,
				//the underlying instance will be "contained"
				return li.getSession()==this;
			}
			else {
				//if it is initialized, see if the underlying
				//instance is contained, since we need to 
				//account for the fact that it might have been
				//evicted
				object = li.getImplementation();
			}
		}
		// A session is considered to contain an entity only if the entity has
		// an entry in the session's persistence context and the entry reports
		// that the entity has not been removed
		EntityEntry entry = persistenceContext.getEntry( object );
		return entry != null && entry.getStatus() != Status.DELETED && entry.getStatus() != Status.GONE;
	}
	
	public Query createQuery(String queryString) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return super.createQuery(queryString);
	}
	
	public SQLQuery createSQLQuery(String sql) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return super.createSQLQuery(sql);
	}

	public Query createSQLQuery(String sql, String returnAlias, Class returnClass) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new SQLQueryImpl(
				sql,
		        new String[] { returnAlias },
		        new Class[] { returnClass },
		        this,
		        factory.getQueryPlanCache().getSQLParameterMetadata( sql )
		);
	}

	public Query createSQLQuery(String sql, String returnAliases[], Class returnClasses[]) {
		errorIfClosed();
		checkTransactionSynchStatus();
		return new SQLQueryImpl(
				sql,
		        returnAliases,
		        returnClasses,
		        this,
		        factory.getQueryPlanCache().getSQLParameterMetadata( sql )
		);
	}

	public ScrollableResults scrollCustomQuery(CustomQuery customQuery, QueryParameters queryParameters) 
	throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();

		if ( log.isTraceEnabled() ) {
			log.trace( "scroll SQL query: " + customQuery.getSQL() );
		}

		CustomLoader loader = new CustomLoader( customQuery, getFactory() );

		autoFlushIfRequired( loader.getQuerySpaces() );

		dontFlushFromFind++; //stops flush being called multiple times if this method is recursively called
		try {
			return loader.scroll(queryParameters, this);
		}
		finally {
			dontFlushFromFind--;
		}
	}

	// basically just an adapted copy of find(CriteriaImpl)
	public List listCustomQuery(CustomQuery customQuery, QueryParameters queryParameters) 
	throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();

		if ( log.isTraceEnabled() ) {
			log.trace( "SQL query: " + customQuery.getSQL() );
		}
		
		CustomLoader loader = new CustomLoader( customQuery, getFactory() );

		autoFlushIfRequired( loader.getQuerySpaces() );

		dontFlushFromFind++;
		boolean success = false;
		try {
			List results = loader.list(this, queryParameters);
			success = true;
			return results;
		}
		finally {
			dontFlushFromFind--;
			afterOperation(success);
		}
	}

	public SessionFactory getSessionFactory() {
		checkTransactionSynchStatus();
		return factory;
	}
	
	public void initializeCollection(PersistentCollection collection, boolean writing) 
	throws HibernateException {
		errorIfClosed();
		checkTransactionSynchStatus();
		InitializeCollectionEventListener[] listener = listeners.getInitializeCollectionEventListeners();
		for ( int i = 0; i < listener.length; i++ ) {
			listener[i].onInitializeCollection( new InitializeCollectionEvent(collection, this) );
		}
	}

	public String bestGuessEntityName(Object object) {
		if (object instanceof HibernateProxy) {
			LazyInitializer initializer = ( ( HibernateProxy ) object ).getHibernateLazyInitializer();
			// it is possible for this method to be called during flush processing,
			// so make certain that we do not accidently initialize an uninitialized proxy
			if ( initializer.isUninitialized() ) {
				return initializer.getEntityName();
			}
			object = initializer.getImplementation();
		}
		EntityEntry entry = persistenceContext.getEntry(object);
		if (entry==null) {
			return guessEntityName(object);
		}
		else {
			return entry.getPersister().getEntityName();
		}
	}
	
	public String getEntityName(Object object) {
		errorIfClosed();
		checkTransactionSynchStatus();
		if (object instanceof HibernateProxy) {
			if ( !persistenceContext.containsProxy( object ) ) {
				throw new TransientObjectException("proxy was not associated with the session");
			}
			object = ( (HibernateProxy) object ).getHibernateLazyInitializer().getImplementation();
		}

		EntityEntry entry = persistenceContext.getEntry(object);
		if ( entry == null ) {
			throwTransientObjectException( object );
		}
		return entry.getPersister().getEntityName();
	}

	private void throwTransientObjectException(Object object) throws HibernateException {
		throw new TransientObjectException(
				"object references an unsaved transient instance - save the transient instance before flushing: " +
				guessEntityName(object)
			);
	}

	public String guessEntityName(Object object) throws HibernateException {
		errorIfClosed();
		String entity = interceptor.getEntityName( object );
		if ( entity == null ) {
			if ( object instanceof Map ) {
				entity = (String) ( (Map) object ).get( DynamicMapInstantiator.KEY );
				if ( entity == null ) {
					throw new HibernateException( "could not determine type of dynamic entity" );
				}
			}
			else if ( object instanceof Element ) {
				// TODO : really need to keep a map of nodeName -> entityName, but that would mean nodeName being distinct
				entity = ( (Element) object ).getName();
			}
			else {
				entity = object.getClass().getName();
			}
		}
		return entity;
	}

	public void cancelQuery() throws HibernateException {
		errorIfClosed();
		getBatcher().cancelLastQuery();
	}

	public Interceptor getInterceptor() {
		checkTransactionSynchStatus();
		return interceptor;
	}

	public int getDontFlushFromFind() {
		return dontFlushFromFind;
	}

	public String toString() {
		StringBuffer buf = new StringBuffer(500)
			.append( "SessionImpl(" );
		if ( !isClosed() ) {
			buf.append(persistenceContext)
				.append(";")
				.append(actionQueue);
		}
		else {
			buf.append("<closed>");
		}
		return buf.append(')').toString();
	}

	public EventListeners getListeners() {
		return listeners;
	}

	public ActionQueue getActionQueue() {
		errorIfClosed();
		checkTransactionSynchStatus();
		return actionQueue;
	}
	
	public PersistenceContext getPersistenceContext() {
		errorIfClosed();
		checkTransactionSynchStatus();
		return persistenceContext;
	}
	
	public SessionStatistics getStatistics() {
		checkTransactionSynchStatus();
		return new SessionStatisticsImpl(this);
	}

	public boolean isEventSource() {
		checkTransactionSynchStatus();
		return true;
	}

	public void setReadOnly(Object entity, boolean readOnly) {
		errorIfClosed();
		checkTransactionSynchStatus();
		persistenceContext.setReadOnly(entity, readOnly);
	}

	public void afterScrollOperation() {
		// nothing to do in a stateful session
	}

	public String getFetchProfile() {
		checkTransactionSynchStatus();
		return fetchProfile;
	}

	public JDBCContext getJDBCContext() {
		errorIfClosed();
		checkTransactionSynchStatus();
		return jdbcContext;
	}

	public void setFetchProfile(String fetchProfile) {
		errorIfClosed();
		checkTransactionSynchStatus();
		this.fetchProfile = fetchProfile;
	}

	private void checkTransactionSynchStatus() {
		if ( jdbcContext != null && !isClosed() ) {
			jdbcContext.registerSynchronizationIfPossible();
		}
	}

	/**
	 * Used by JDK serialization...
	 *
	 * @param ois The input stream from which we are being read...
	 * @throws IOException Indicates a general IO stream exception
	 * @throws ClassNotFoundException Indicates a class resolution issue
	 */
	private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
		log.trace( "deserializing session" );

		boolean isRootSession = ois.readBoolean();
		connectionReleaseMode = ConnectionReleaseMode.parse( ( String ) ois.readObject() );
		entityMode = EntityMode.parse( ( String ) ois.readObject() );
		autoClear = ois.readBoolean();
		flushMode = FlushMode.parse( ( String ) ois.readObject() );
		cacheMode = CacheMode.parse( ( String ) ois.readObject() );
		flushBeforeCompletionEnabled = ois.readBoolean();
		autoCloseSessionEnabled = ois.readBoolean();
		fetchProfile = ( String ) ois.readObject();
		interceptor = ( Interceptor ) ois.readObject();

		factory = SessionFactoryImpl.deserialize( ois );
		listeners = factory.getEventListeners();

		if ( isRootSession ) {
			jdbcContext = JDBCContext.deserialize( ois, this, interceptor );
		}

		persistenceContext = StatefulPersistenceContext.deserialize( ois, this );
		actionQueue = ActionQueue.deserialize( ois, this );

		enabledFilters = ( Map ) ois.readObject();
		childSessionsByEntityMode = ( Map ) ois.readObject();

		Iterator iter = enabledFilters.values().iterator();
		while ( iter.hasNext() ) {
			( ( FilterImpl ) iter.next() ).afterDeserialize(factory);
		}

		if ( isRootSession && childSessionsByEntityMode != null ) {
			iter = childSessionsByEntityMode.values().iterator();
			while ( iter.hasNext() ) {
				final SessionImpl child = ( ( SessionImpl ) iter.next() );
				child.rootSession = this;
				child.jdbcContext = this.jdbcContext;
			}
		}
	}

	/**
	 * Used by JDK serialization...
	 *
	 * @param oos The output stream to which we are being written...
	 * @throws IOException Indicates a general IO stream exception
	 */
	private void writeObject(ObjectOutputStream oos) throws IOException {
		if ( !jdbcContext.getConnectionManager().isReadyForSerialization() ) {
			throw new IllegalStateException( "Cannot serialize a session while connected" );
		}

		log.trace( "serializing session" );

		oos.writeBoolean( rootSession == null );
		oos.writeObject( connectionReleaseMode.toString() );
		oos.writeObject( entityMode.toString() );
		oos.writeBoolean( autoClear );
		oos.writeObject( flushMode.toString() );
		oos.writeObject( cacheMode.toString() );
		oos.writeBoolean( flushBeforeCompletionEnabled );
		oos.writeBoolean( autoCloseSessionEnabled );
		oos.writeObject( fetchProfile );
		// we need to writeObject() on this since interceptor is user defined
		oos.writeObject( interceptor );

		factory.serialize( oos );

		if ( rootSession == null ) {
			jdbcContext.serialize( oos );
		}

		persistenceContext.serialize( oos );
		actionQueue.serialize( oos );

		// todo : look at optimizing these...
		oos.writeObject( enabledFilters );
		oos.writeObject( childSessionsByEntityMode );
	}
}