多数据源---SessionFactory
之前做过一个多database的例子，当时没有达到动态更换数据源的目的。
后来做了个多session工厂的例子，达到了动态更换数据源的目的了。在网上有些例子，
不过感觉有帮助但是不全，特此把我自己的弄得贴出来，如果说的不清楚的话，可以下载
附件看代码！
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spring配置文件
<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"xmlns:aop="http://www.springframework.org/schema/aop"xmlns:tx="http://www.springframework.org/schema/tx"xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd"default-autowire="byName"><context:annotation-config /><bean id="parentDataSource"value="root"></property><property name="password" value="hejie"></property></bean><bean id="primaryDataSource" parent="parentDataSource"><property name="url"><value>jdbc:mysql://localhost:3306/test1</value></property></bean><bean id="backupDataSource" parent="parentDataSource"><property name="url"><value>jdbc:mysql://localhost:3306/test2</value></property></bean><!-- <bean id="dataSource" scope="prototype"value-ref="primaryDataSource" /><entry key="guest1" value-ref="backupDataSource" /></map></property><property name="defaultTargetDataSource" ref="primaryDataSource" /></bean> --><bean id="sessionFactory1"/></property><property name="hibernateProperties"><props><prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop><prop key="hibernate.show_sql">true</prop><prop key="hibernate.format_sql">true</prop><prop key="hibernate.hbm2ddl.auto">update</prop><prop key="hibernate.current_session_context_class">thread</prop><prop key="hibernate.show_sql">false</prop></props></property><property name="mappingResources"><list><value>com/mul/entity/DataEntity.hbm.xml</value></list></property><property name="exposeTransactionAwareSessionFactory"><value>false</value></property></bean><bean id="sessionFactory2"/></property><property name="hibernateProperties"><props><prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop><prop key="hibernate.show_sql">true</prop><prop key="hibernate.format_sql">true</prop><prop key="hibernate.hbm2ddl.auto">update</prop><prop key="hibernate.current_session_context_class">thread</prop><prop key="hibernate.show_sql">false</prop></props></property><property name="mappingResources"><list><value>com/mul/entity/DataEntity.hbm.xml</value></list></property><property name="exposeTransactionAwareSessionFactory"><value>false</value></property></bean><bean id="sessionFactory" ref="sessionFactory" /><!--<property name="hibernateManagedSession" value="false"/>--></bean><tx:annotation-driven transaction-manager="transactionManager" /><context:component-scan base-package="com.mul" /><aop:config><aop:pointcut id="testservice"expression="execution(* com.mul.service.*Service.*(..))" /><aop:advisor id="testServiceAd" advice-ref="txAdvice" pointcut-ref="testservice" /></aop:config><tx:advice id="txAdvice" transaction-manager="transactionManager"><tx:attributes><tx:method name="*" propagation="REQUIRED" rollback-for="java.lang.Exception"/><!--<tx:method name="*" propagation="REQUIRED"/>--></tx:attributes></tx:advice><!-- dao --><bean id="dataEntityDao" name="code"><?xml version="1.0" encoding="utf-8"?><!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><!--Mapping file autogenerated by MyEclipse Persistence Tools--><hibernate-mapping><class name="com.mul.entity.DataEntity" table="dataentity"mutable="false"><id name="id" type="java.lang.Integer"><column name="id" /><generator type="java.lang.String"><column name="name" length="128" /></property><property name="age"><column name="age" /></property></class></hibernate-mapping>
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dao
package com.mul.dao;import org.springframework.orm.hibernate3.support.HibernateDaoSupport;import com.mul.entity.DataEntity;public class DataEntityDao extends HibernateDaoSupport{public DataEntity save(DataEntity de){this.getSession().save(de);return de;}}?
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service
package com.mul.service;import com.mul.dao.DataEntityDao;import com.mul.entity.DataEntity;import com.mul.spring.CustomerContextHolder;import com.mul.spring.DynamicDataSourceType;public class DataEntityService {private DataEntityDao dataEntityDao ;public DataEntity save(DataEntity de){System.out.println("保存到s1："+DynamicDataSourceType.S1);this.dataEntityDao.save(de);return de;}public DataEntity save2(DataEntity de){System.out.println("保存到s2："+DynamicDataSourceType.S2);this.dataEntityDao.save(de);return de;}public DataEntityDao getDataEntityDao() {return dataEntityDao;}public void setDataEntityDao(DataEntityDao dataEntityDao) {this.dataEntityDao = dataEntityDao;}}?
servlet： 建议使用struts试一试，在servlet中跟我在网上查的不同
package com.mul.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.mul.entity.DataEntity;import com.mul.service.DataEntityService;import com.mul.spring.CustomerContextHolder;import com.mul.spring.DataSourceTypeChoose;import com.mul.spring.DataSourceTypeKey;import com.mul.spring.DynamicDataSourceType;public class mulDataServlet extends HttpServlet {public mulDataServlet() {super();}public void destroy() {super.destroy(); }public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doPost(request, response);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {String name = request.getParameter("name");String age = request.getParameter("age");String db = request.getParameter("db");DataEntity de = new DataEntity(name,new Integer(age==null?"16":age));System.out.println("要保存的对象："+de);//if("admin1".equals(db))//DataSourceTypeChoose.setThreadLocal(DataSourceTypeKey.ADMIN);//else//DataSourceTypeChoose.setThreadLocal(DataSourceTypeKey.GUEST);if(DataSourceTypeKey.appContext == null)DataSourceTypeKey.appContext = new ClassPathXmlApplicationContext("/applicationContext.xml");DataEntityService dataEntityService = (DataEntityService)DataSourceTypeKey.appContext.getBean("dataEntityService");System.out.println("开始保存到数据库");if("admin1".equals(db)){//必须在save方法CustomerContextHolder.setCustomerType(DynamicDataSourceType.S1);dataEntityService.save(de);}else{CustomerContextHolder.setCustomerType(DynamicDataSourceType.S2);dataEntityService.save2(de);}//ApplicationContext appContext = new ClassPathXmlApplicationContext("/applicationContext.xml");//DataEntityService dataE = (DataEntityService)appContext.getBean("dataEntityService");//dataE.save(de);request.setAttribute("de", de);request.getRequestDispatcher("/index.jsp").forward(request, response);}/** * Initialization of the servlet. <br> * * @throws ServletException if an error occurs */public void init() throws ServletException {// Put your code here}}?
辅助类，为了线程安全
package com.mul.spring;public class CustomerContextHolder {private static final ThreadLocal contextHolder = new ThreadLocal();public static void setCustomerType(String customerType) { System.out.println(customerType+" customerType cannot be null"); contextHolder.set(customerType);}public static String getCustomerType() { return (String) contextHolder.get();}public static void clearCustomerType() { contextHolder.remove();}}?
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统一管理session工厂的id
package com.mul.spring;public class DynamicDataSourceType {public static final String S1= "sessionFactory1";public static final String S2= "sessionFactory2";}?
多sessionFactory的实现
package com.mul.spring;import java.io.Serializable;import java.lang.ref.Reference;import java.sql.Connection;import java.util.Map;import java.util.Set;import javax.naming.NamingException;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.hibernate.HibernateException;import org.hibernate.Interceptor;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.StatelessSession;import org.hibernate.engine.FilterDefinition;import org.hibernate.metadata.ClassMetadata;import org.hibernate.metadata.CollectionMetadata;import org.hibernate.stat.Statistics;import org.springframework.beans.factory.NoSuchBeanDefinitionException;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;/** * 多SessionFactory 的一个实现 * @author hejie */public class MultiSessionFactory implements SessionFactory, ApplicationContextAware {private static final long serialVersionUID = 2064557324203496378L;private static final Log log = LogFactory.getLog(MultiSessionFactory.class);private ApplicationContext applicationContext = null;private SessionFactory sessionFactory = null;public ApplicationContext getApplicationContext() { return applicationContext;}public void setApplicationContext(ApplicationContext applicationContext) { this.applicationContext = applicationContext;}//在每次拿到bean时都会检查你当前的sessionFactory，sessionFactoryName就是bean的idpublic SessionFactory getSessionFactory(String sessionFactoryName) { System.out.println("=========sessionFactoryName:"+sessionFactoryName); try{ if(sessionFactoryName==null||sessionFactoryName.equals("")){ return sessionFactory; } return (SessionFactory)this.getApplicationContext().getBean(sessionFactoryName); }catch(NoSuchBeanDefinitionException ex){ throw new RuntimeException("There is not the sessionFactory <name:"+sessionFactoryName+"> in the applicationContext!"); }}public SessionFactory getSessionFactory() { String sessionFactoryName = CustomerContextHolder.getCustomerType(); return getSessionFactory(sessionFactoryName);}public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory;}/* (non-Javadoc)* @see org.hibernate.SessionFactory#close()*/public void close() throws HibernateException { getSessionFactory().close();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evict(java.lang.Class)*/public void evict(Class persistentClass) throws HibernateException { getSessionFactory().evict(persistentClass);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evict(java.lang.Class, java.io.Serializable)*/public void evict(Class persistentClass, Serializable id) throws HibernateException { getSessionFactory().evict(persistentClass, id);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictCollection(java.lang.String)*/public void evictCollection(String roleName) throws HibernateException { getSessionFactory().evictCollection(roleName);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictCollection(java.lang.String, java.io.Serializable)*/public void evictCollection(String roleName, Serializable id) throws HibernateException { getSessionFactory().evictCollection(roleName, id);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictEntity(java.lang.String)*/public void evictEntity(String entityName) throws HibernateException { getSessionFactory().evictEntity(entityName);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictEntity(java.lang.String, java.io.Serializable)*/public void evictEntity(String entityName, Serializable id) throws HibernateException { getSessionFactory().evictEntity(entityName, id);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictQueries()*/public void evictQueries() throws HibernateException { getSessionFactory().evictQueries();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#evictQueries(java.lang.String)*/public void evictQueries(String cacheRegion) throws HibernateException { getSessionFactory().evictQueries(cacheRegion);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getAllClassMetadata()*/public Map getAllClassMetadata() throws HibernateException { return getSessionFactory().getAllClassMetadata();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getAllCollectionMetadata()*/public Map getAllCollectionMetadata() throws HibernateException { return getSessionFactory().getAllCollectionMetadata();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getClassMetadata(java.lang.Class)*/public ClassMetadata getClassMetadata(Class persistentClass) throws HibernateException { return getSessionFactory().getClassMetadata(persistentClass);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getClassMetadata(java.lang.String)*/public ClassMetadata getClassMetadata(String entityName) throws HibernateException { return getSessionFactory().getClassMetadata(entityName);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getCollectionMetadata(java.lang.String)*/public CollectionMetadata getCollectionMetadata(String roleName) throws HibernateException { return getSessionFactory().getCollectionMetadata(roleName);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getCurrentSession()*/public org.hibernate.classic.Session getCurrentSession() throws HibernateException { return getSessionFactory().getCurrentSession();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getDefinedFilterNames()*/public Set getDefinedFilterNames() { return getSessionFactory().getDefinedFilterNames();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getFilterDefinition(java.lang.String)*/public FilterDefinition getFilterDefinition(String filterName) throws HibernateException { return getSessionFactory().getFilterDefinition(filterName);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#getStatistics()*/public Statistics getStatistics() { return getSessionFactory().getStatistics();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#isClosed()*/public boolean isClosed() { return getSessionFactory().isClosed();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openSession()*/public org.hibernate.classic.Session openSession() throws HibernateException { return getSessionFactory().openSession();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openSession(java.sql.Connection)*/public org.hibernate.classic.Session openSession(Connection connection) { return getSessionFactory().openSession(connection);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openSession(org.hibernate.Interceptor)*/public org.hibernate.classic.Session openSession(Interceptor interceptor) throws HibernateException { return getSessionFactory().openSession(interceptor);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openSession(java.sql.Connection, org.hibernate.Interceptor)*/public org.hibernate.classic.Session openSession(Connection connection, Interceptor interceptor) { return getSessionFactory().openSession(connection, interceptor);}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openStatelessSession()*/public StatelessSession openStatelessSession() { return getSessionFactory().openStatelessSession();}/* (non-Javadoc)* @see org.hibernate.SessionFactory#openStatelessSession(java.sql.Connection)*/public StatelessSession openStatelessSession(Connection connection) { return getSessionFactory().openStatelessSession(connection);}/* (non-Javadoc)* @see javax.naming.Referenceable#getReference()*/public javax.naming.Reference getReference() throws NamingException { return getSessionFactory().getReference();}}?
只创建一个application（struts等就不需要了）
package com.mul.spring;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class DataSourceTypeKey {public static ApplicationContext appContext ; }?
在servlet调用service时他去调用MultiSessionFactory openSession()
注意：发布项目是去掉asm-2.2.3.jar包
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1 楼 zmty123 2011-04-11 我问一下，你的dao是extends HibernateDaoSupport。这样sessionFactory可以得到。