hibernate 启动代码分析

从上一篇源代码阅读看，这hibernate套的还真是有点深，这次主要看一下他的启动过程

// configures settings from hibernate.cfg.xml
Configuration cfg=new Configuration().configure();
sessionFactory = cfg.buildSessionFactory();

先初始化Configuration 对象，这个类里保存运行时的配置信息，

protected Map<String, PersistentClass> classes;
	protected Map<String, String> imports;
	protected Map<String, Collection> collections;
	protected Map<String, Table> tables;
	protected List<AuxiliaryDatabaseObject> auxiliaryDatabaseObjects;

	protected Map<String, NamedQueryDefinition> namedQueries;
	protected Map<String, NamedSQLQueryDefinition> namedSqlQueries;
	protected Map<String, ResultSetMappingDefinition> sqlResultSetMappings;

	protected Map<String, TypeDef> typeDefs;
	protected Map<String, FilterDefinition> filterDefinitions;
	protected Map<String, FetchProfile> fetchProfiles;

	protected Map tableNameBinding;
	protected Map columnNameBindingPerTable;

	protected List<SecondPass> secondPasses;
	protected List<Mappings.PropertyReference> propertyReferences;
	protected Map<ExtendsQueueEntry, ?> extendsQueue;

	protected Map<String, SQLFunction> sqlFunctions;

解析获得session factory里面的配置信息

private void parseSessionFactory(Element sfNode, String name) {
		Iterator elements = sfNode.elementIterator();
		while ( elements.hasNext() ) {
			Element subelement = (Element) elements.next();
			String subelementName = subelement.getName();
			if ( "mapping".equals( subelementName ) ) {
				parseMappingElement( subelement, name );
			}
			else if ( "class-cache".equals( subelementName ) ) {
				String className = subelement.attributeValue( "class" );
				Attribute regionNode = subelement.attribute( "region" );
				final String region = ( regionNode == null ) ? className : regionNode.getValue();
				boolean includeLazy = !"non-lazy".equals( subelement.attributeValue( "include" ) );
				setCacheConcurrencyStrategy( className, subelement.attributeValue( "usage" ), region, includeLazy );
			}
			else if ( "collection-cache".equals( subelementName ) ) {
				String role = subelement.attributeValue( "collection" );
				Attribute regionNode = subelement.attribute( "region" );
				final String region = ( regionNode == null ) ? role : regionNode.getValue();
				setCollectionCacheConcurrencyStrategy( role, subelement.attributeValue( "usage" ), region );
			}
			else if ( "listener".equals( subelementName ) ) {
				parseListener( subelement );
			}
			else if ( "event".equals( subelementName ) ) {
				parseEvent( subelement );
			}
		}
	}

这里主要看下对mapping 节点的处理

private XmlDocument add(InputSource inputSource, Origin origin) {
		XmlDocument metadataXml = MappingReader.INSTANCE.readMappingDocument( entityResolver, inputSource, origin );
		add( metadataXml );
		return metadataXml;
	}

这里的　metadataXml 　实际上是一个mapping文件的对象，包含了一个hbm.xml里面的配置信息。建立相应的pojo类是在build session factory的时候，