sessionfactoryimpl.java

介绍了hibernate的入门有一些基本常用的事例

//$Id: SessionFactoryImpl.java,v 1.70 2005/04/13 20:46:19 steveebersole Exp $
package org.hibernate.impl;

import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamException;
import java.io.Serializable;
import java.sql.Connection;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import javax.naming.NamingException;
import javax.naming.Reference;
import javax.naming.StringRefAddr;
import javax.transaction.Synchronization;
import javax.transaction.SystemException;
import javax.transaction.Transaction;
import javax.transaction.TransactionManager;

import net.sf.cglib.core.KeyFactory;

import org.apache.commons.collections.ReferenceMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.AssertionFailure;
import org.hibernate.EntityMode;
import org.hibernate.HibernateException;
import org.hibernate.Interceptor;
import org.hibernate.MappingException;
import org.hibernate.QueryException;
import org.hibernate.SessionFactory;
import org.hibernate.cache.Cache;
import org.hibernate.cache.CacheConcurrencyStrategy;
import org.hibernate.cache.CacheFactory;
import org.hibernate.cache.CacheKey;
import org.hibernate.cache.QueryCache;
import org.hibernate.cache.UpdateTimestampsCache;
import org.hibernate.cfg.Configuration;
import org.hibernate.cfg.Settings;
import org.hibernate.connection.ConnectionProvider;
import org.hibernate.dialect.Dialect;
import org.hibernate.engine.FilterDefinition;
import org.hibernate.engine.Mapping;
import org.hibernate.engine.NamedQueryDefinition;
import org.hibernate.engine.NamedSQLQueryDefinition;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.event.SessionEventListenerConfig;
import org.hibernate.exception.SQLExceptionConverter;
import org.hibernate.hql.FilterTranslator;
import org.hibernate.hql.QuerySplitter;
import org.hibernate.hql.QueryTranslator;
import org.hibernate.id.IdentifierGenerator;
import org.hibernate.id.UUIDHexGenerator;
import org.hibernate.jdbc.BatcherFactory;
import org.hibernate.mapping.Collection;
import org.hibernate.mapping.PersistentClass;
import org.hibernate.metadata.ClassMetadata;
import org.hibernate.metadata.CollectionMetadata;
import org.hibernate.persister.PersisterFactory;
import org.hibernate.persister.collection.CollectionPersister;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.persister.entity.Queryable;
import org.hibernate.pretty.MessageHelper;
import org.hibernate.stat.Statistics;
import org.hibernate.stat.StatisticsImpl;
import org.hibernate.stat.StatisticsImplementor;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.hibernate.tool.hbm2ddl.SchemaUpdate;
import org.hibernate.transaction.TransactionFactory;
import org.hibernate.type.Type;
import org.hibernate.util.CollectionHelper;
import org.hibernate.util.JTAHelper;
import org.hibernate.util.ReflectHelper;


/**
 * Concrete implementation of the <tt>SessionFactory</tt> interface. Has the following
 * responsibilites
 * <ul>
 * <li>caches configuration settings (immutably)
 * <li>caches "compiled" mappings ie. <tt>EntityPersister</tt>s and
 *     <tt>CollectionPersister</tt>s (immutable)
 * <li>caches "compiled" queries (memory sensitive cache)
 * <li>manages <tt>PreparedStatement</tt>s
 * <li> delegates JDBC <tt>Connection</tt> management to the <tt>ConnectionProvider</tt>
 * <li>factory for instances of <tt>SessionImpl</tt>
 * </ul>
 * This class must appear immutable to clients, even if it does all kinds of caching
 * and pooling under the covers. It is crucial that the class is not only thread
 * safe, but also highly concurrent. Synchronization must be used extremely sparingly.
 *
 * @see org.hibernate.connection.ConnectionProvider
 * @see org.hibernate.classic.Session
 * @see org.hibernate.hql.QueryTranslator
 * @see org.hibernate.persister.entity.EntityPersister
 * @see org.hibernate.persister.collection.CollectionPersister
 * @author Gavin King
 */
public final class SessionFactoryImpl implements SessionFactory, SessionFactoryImplementor {

	private final String name;
	private final String uuid;

	private final transient Map entityPersisters;
	private final transient Map classMetadata;
	private final transient Map collectionPersisters;
	private final transient Map collectionMetadata;
	private final transient Map identifierGenerators;
	private final transient Map namedQueries;
	private final transient Map namedSqlQueries;
	private final transient Map filters;
	private final transient Map imports;
	private final transient Interceptor interceptor;
	private final transient Settings settings;
	private final transient Properties properties;
	private transient SchemaExport schemaExport;
	private final transient TransactionManager transactionManager;
	private final transient QueryCache queryCache;
	private final transient UpdateTimestampsCache updateTimestampsCache;
	private final transient Map queryCaches;
	private final transient Map allCacheRegions = new HashMap();
	private final transient StatisticsImpl statistics = new StatisticsImpl(this);

	private static final IdentifierGenerator UUID_GENERATOR = new UUIDHexGenerator();

    private SessionEventListenerConfig sessionEventListenerConfig;

	private transient Map currentSessionMap;

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

	public SessionFactoryImpl(
			Configuration cfg, 
			Mapping mapping,
			Settings settings, 
			SessionEventListenerConfig listeners) 
	throws HibernateException {

		log.info("building session factory");

		this.properties = cfg.getProperties();
		this.interceptor = cfg.getInterceptor();
		this.settings = settings;
        this.sessionEventListenerConfig = listeners;
        this.filters = cfg.getFilterDefinitions();

		if ( log.isDebugEnabled() ) {
			log.debug("Session factory constructed with filter configurations : " + filters);
		}

		if ( log.isDebugEnabled() ) log.debug(
			"instantiating session factory with properties: " + properties 
		);

		// Caches
		settings.getCacheProvider().start( properties );

		//Generators:
		
		identifierGenerators = new HashMap();
		Iterator classes = cfg.getClassMappings();
		while ( classes.hasNext() ) {
			PersistentClass model = (PersistentClass) classes.next();
			if ( !model.isInherited() ) {
				IdentifierGenerator generator = model.getIdentifier().createIdentifierGenerator( 
						settings.getDialect(),
						settings.getDefaultCatalogName(),
						settings.getDefaultSchemaName(), 
						model.getEntityName()
				);
				identifierGenerators.put( model.getEntityName(), generator );
			}
		}
		
		//Persisters:

		Map caches = new HashMap();
		entityPersisters = new HashMap();
		Map classMeta = new HashMap();
		classes = cfg.getClassMappings();
		while ( classes.hasNext() ) {
			PersistentClass model = (PersistentClass) classes.next();
			String cacheRegion = model.getRootClass().getCacheRegionName();
			CacheConcurrencyStrategy cache = (CacheConcurrencyStrategy) caches.get(cacheRegion);
			if (cache==null) {
				cache = CacheFactory.createCache(
					model.getCacheConcurrencyStrategy(),
					cacheRegion,
					model.isMutable(),
					settings,
					properties
				);
				if (cache!=null) {
					caches.put(cacheRegion, cache);
					allCacheRegions.put( cache.getRegionName(), cache.getCache() );
				}
			}
			EntityPersister cp = PersisterFactory.createClassPersister(model, cache, this, mapping);
			entityPersisters.put( model.getEntityName(), cp );
			classMeta.put( model.getEntityName(), cp.getClassMetadata() );
		}
		classMetadata = Collections.unmodifiableMap(classMeta);

		collectionPersisters = new HashMap();
		Iterator collections = cfg.getCollectionMappings();
		while ( collections.hasNext() ) {
			Collection model = (Collection) collections.next();
			CacheConcurrencyStrategy cache = CacheFactory.createCache(
				model.getCacheConcurrencyStrategy(),
				model.getCacheRegionName(),
				true,
				settings,
				properties
			);
			if (cache!=null) allCacheRegions.put( cache.getRegionName(), cache.getCache() );
			CollectionPersister persister = PersisterFactory.createCollectionPersister(cfg, model, cache, this);
			collectionPersisters.put( model.getRole(), persister.getCollectionMetadata() );
		}
		collectionMetadata = Collections.unmodifiableMap(collectionPersisters);

		//Named Queries:
		// TODO: precompile and cache named queries
		namedQueries = new HashMap( cfg.getNamedQueries() );
		namedSqlQueries = new HashMap( cfg.getNamedSQLQueries() );
		imports = new HashMap( cfg.getImports() );

		// after *all* persisters and named queries are registered
		Iterator iter = entityPersisters.values().iterator();
		while ( iter.hasNext() ) {
			( (EntityPersister) iter.next() ).postInstantiate();
		}
		iter = collectionPersisters.values().iterator();
		while ( iter.hasNext() ) {
			( (CollectionPersister) iter.next() ).postInstantiate();
		}

		//JNDI + Serialization:

		name = settings.getSessionFactoryName();
		try {
			uuid = (String) UUID_GENERATOR.generate(null, null);
		}
		catch (Exception e) {
			throw new AssertionFailure("Could not generate UUID");
		}
		SessionFactoryObjectFactory.addInstance(uuid, name, this, properties);

		log.debug("instantiated session factory");

		if ( settings.isAutoCreateSchema() ) new SchemaExport(cfg).create(false, true);
		if ( settings.isAutoUpdateSchema() ) new SchemaUpdate(cfg).execute(false, true);
		if ( settings.isAutoDropSchema() ) schemaExport = new SchemaExport(cfg);

		if ( settings.getTransactionManagerLookup()!=null ) {
			log.debug("obtaining JTA TransactionManager");
			transactionManager = settings.getTransactionManagerLookup().getTransactionManager(properties);
		}
		else {
			transactionManager = null;
		}

		if ( settings.isQueryCacheEnabled() ) {
			updateTimestampsCache = new UpdateTimestampsCache(settings, properties);
			queryCache = settings.getQueryCacheFactory()
			        .getQueryCache(null, updateTimestampsCache, settings, properties);
			queryCaches = new HashMap();
			allCacheRegions.put( updateTimestampsCache.getRegionName(), updateTimestampsCache.getCache() );
			allCacheRegions.put( queryCache.getRegionName(), queryCache.getCache() );
		}
		else {
			updateTimestampsCache = null;
			queryCache = null;
			queryCaches = null;
		}

		//checking for named queries
		Map errors = checkNamedQueries();
		if ( !errors.isEmpty() ) {
			Set keys = errors.keySet();
			StringBuffer failingQueries = new StringBuffer("Errors in named queries: ");
			for ( Iterator iterator = keys.iterator() ; iterator.hasNext() ; ) {
				String queryName = (String) iterator.next();
				HibernateException e = (HibernateException) errors.get(queryName);
				failingQueries.append(queryName);
				if ( iterator.hasNext() ) failingQueries.append(", ");
				log.error("Error in named query: " + queryName, e);
			}
			throw new HibernateException( failingQueries.toString() );
		}
		
		//stats
		getStatistics().setStatisticsEnabled( settings.isStatisticsEnabled() );
	}

	// Emulates constant time LRU/MRU algorithms for cache
	// It is better to hold strong references on some (LRU/MRU) queries
	private static final int MAX_STRONG_REF_COUNT = 128; //TODO: configurable?
	private final transient Object[] strongRefs = new Object[MAX_STRONG_REF_COUNT]; //strong reference to MRU queries
	private transient int strongRefIndex = 0;
	private final transient Map softQueryCache = new ReferenceMap(ReferenceMap.SOFT, ReferenceMap.SOFT) ;
	// both keys and values may be soft since value keeps a hard ref to the key (and there is a hard ref to MRU values)

	//returns generated class instance
	private static final QueryCacheKeyFactory QUERY_KEY_FACTORY;
	private static final FilterCacheKeyFactory FILTER_KEY_FACTORY;
	static {
		QUERY_KEY_FACTORY = (QueryCacheKeyFactory) KeyFactory.create(QueryCacheKeyFactory.class);
		FILTER_KEY_FACTORY = (FilterCacheKeyFactory) KeyFactory.create(FilterCacheKeyFactory.class);
	}

	static interface QueryCacheKeyFactory {
		//Will not recalculate hashKey for constant queries
		Object newInstance(String query, boolean scalar);