spring+JPA 多数据库整合？

Question

spring+JPA 多数据库整合？
请

Answer 1

persistence.xml配置多个数据库
applicationContext.xml统一管理
web.xml加载
dao service 调用

Answer 2

http://www.cnblogs.com/linjiqin/archive/2011/02/12/1952904.html
看看这个，在测试情况下没问题，可一旦加入web.xml启动tomcat就不行了。

Answer 3

我的配置
persistence.xml文件：<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
    http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" version="1.0">
    <persistence-unit name="fmspro" transaction-type="RESOURCE_LOCAL">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <properties>
<property name="hibernate.connection.driver_class"
value="com.ibm.db2.jcc.DB2Driver" />
<property name="hibernate.connection.url"
value="" />
<property name="hibernate.connection.username"
value="" />
<property name="hibernate.connection.password"
value="" />
<property name="hibernate.hbm2ddl.auto" value="update"/>
</properties>
    </persistence-unit>
    <persistence-unit name="idpro" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>com.fms.bean.staffinfo.Idreader</class>
<properties>
<property name="hibernate.connection.driver_class"
value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
<property name="hibernate.connection.url"
value="" />
<property name="hibernate.connection.username"
value="" />
<property name="hibernate.connection.password"
value="" />
</properties>
    </persistence-unit>
</persistence>
applicationContext.xml文件配置：<?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/aop   
           http://www.springframework.org/schema/aop/spring-aop-2.5.xsd   
           http://www.springframework.org/schema/tx   
           http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">
<context:component-scan base-package="com.fms"/>
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
<property name="persistenceUnitName" value="fmspro"></property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>
<tx:annotation-driven transaction-manager="transactionManager"/>
<bean id="entityManagerFactory1"
class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
<property name="persistenceUnitName" value="idpro"></property>
</bean>
<bean id="transactionManager1" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory1"/>
</bean>
<tx:annotation-driven transaction-manager="transactionManager1"/>
<bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"></bean>
</beans>
web.xml文件配置：<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
xmlns="http://java.sun.com/xml/ns/javaee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
<init-param>
<param-name>entityManagerFactoryBeanName</param-name>
<param-value>entityManagerFactory</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
<init-param>
<param-name>actionPackages</param-name>
<param-value>com.fms.web.action</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
    <welcome-file>index.html</welcome-file>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>大家看看

Answer 4

启动错误是：信息: Initializing Spring root WebApplicationContext
2011-3-2 13:31:33 org.apache.catalina.core.StandardContext listenerStart
严重: Exception sending context initialized event to listener instance of class 
org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 
'canteenServiceImpl': Injection of persistence fields failed; nested exception is 
org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type 
[javax.persistence.EntityManagerFactory] is defined: expected single bean but found 2
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterIns
tantiation(PersistenceAnnotationBeanPostProcessor.java:311)
at 
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean
(AbstractAutowireCapableBeanFactory.java:959)
at 
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean
(AbstractAutowireCapableBeanFactory.java:472)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run
(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(Native Method)
at 
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean
(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
at 
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton
(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean
(AbstractBeanFactory.java:261)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:164)
at 
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons
(DefaultListableBeanFactory.java:429)
at 
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization
(AbstractApplicationContext.java:728)
at org.springframework.context.support.AbstractApplicationContext.refresh
(AbstractApplicationContext.java:380)
at org.springframework.web.context.ContextLoader.createWebApplicationContext
(ContextLoader.java:255)
at org.springframework.web.context.ContextLoader.initWebApplicationContext
(ContextLoader.java:199)
at org.springframework.web.context.ContextLoaderListener.contextInitialized
(ContextLoaderListener.java:45)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4205)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4704)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:601)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1079)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:1002)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:506)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1315)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent
(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1061)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke
(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [javax.persistence.EntityManagerFactory] is defined: expected single bean but found 2
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findDefaultEntityMa
nagerFactory(PersistenceAnnotationBeanPostProcessor.java:514)
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findEntityManagerFa
ctory(PersistenceAnnotationBeanPostProcessor.java:473)
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.
resolveEntityManager(PersistenceAnnotationBeanPostProcessor.java:599)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.getResourceToInject(PersistenceAnnotationBeanPostProcessor.java:570)
at 
org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject
(InjectionMetadata.java:180)
at org.springframework.beans.factory.annotation.InjectionMetadata.injectFields
(InjectionMetadata.java:105)
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(PersistenceAnnotationBeanPostProcessor.java:308)
... 40 more
13:31:33,906 ERROR ContextLoader:215 - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 
'canteenServiceImpl': Injection of persistence fields failed; nested exception is 
org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type 
[javax.persistence.EntityManagerFactory] is defined: expected single bean but found 2
at 
org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterIns
tantiation(PersistenceAnnotationBeanPostProcessor.java:311)
at 

Answer 5

org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean
(AbstractAutowireCapableBeanFactory.java:959)
at 
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean
(AbstractAutowireCapableBeanFactory.java:472)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run
(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(Native Method)
at 
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean
(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject
(AbstractBeanFactory.java:264)
at 
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton
(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean
(AbstractBeanFactory.java:261)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:164)
at 
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
at 
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization
(AbstractApplicationContext.java:728)
at org.springframework.context.support.AbstractApplicationContext.refresh
(AbstractApplicationContext.java:380)
at org.springframework.web.context.ContextLoader.createWebApplicationContext
(ContextLoader.java:255)
at org.springframework.web.context.ContextLoader.initWebApplicationContext
(ContextLoader.java:199)
at org.springframework.web.context.ContextLoaderListener.contextInitialized
(ContextLoaderListener.java:45)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4205)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4704)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:601)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1079)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:1002)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:506)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1315)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent
(LifecycleSupport.java:142)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1061)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [javax.persistence.EntityManagerFactory] is defined: expected single bean but found 2
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findDefaultEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:514)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:473)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.resolveEntityManager(PersistenceAnnotationBeanPostProcessor.java:599)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.getResourceToInject(PersistenceAnnotationBeanPostProcessor.java:570)
at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:180)
at org.springframework.beans.factory.annotation.InjectionMetadata.injectFields(InjectionMetadata.java:105)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(PersistenceAnnotationBeanPostProcessor.java:308)
... 40 more

Answer 6

这样肯定会有错误，我也是这样的，好像意思是说  entityManagerFactory只能是单实例的。