Spring에서 multiple JPA persistence units 세팅

Spring에서 다수의 JPA persistence units 을 세팅하려다 아래와 같이 에러가 나서 애먹었다;;

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [spring/applicationContext-jpa.xml]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: No single default persistence unit defined in {classpath:META-INF/persistence.xml}  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1420)  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)

먼저 persistence.xml 에 아래와 같이 persistence-unit 을 teacher라는 이름으로 추가하고..

<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="student"/>     <persistence-unit name="teacher"/>          </persistence>

아래와 같이 applicationContext-jpa.xml 라는 파일 내 entityManagerFactory bean  정의 부분의 property에

persistenceUnitName을 teacher라는 value 값으로 추가 했더니 나온 에러였다.

<bean id="entityManagerFactory"   class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">   <property name="dataSource" ref="dataSource" />   <property name="persistenceUnitName" value="student" />   <property name="persistenceUnitName" value="teacher" />      <property name="jpaVendorAdapter">    <!-- Use Hibernate as JPA engine -->    <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}" />    <!-- <bean class="org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}"/> -->   </property>   <property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml" />  </bean>

결론은 한개의 entityManagerFactory bean에 복수의 persistenceUnitName을 지정할 수 없다는것!

따라서 아래와 같이 entityMangerFactory2 라는 bean을 추가 생성하고

<!-- JPA EntityManagerFactory -->  <bean id="entityManagerFactory"   class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">   <property name="dataSource" ref="dataSource" />   <property name="persistenceUnitName" value="student" />      <property name="jpaVendorAdapter">    <!-- Use Hibernate as JPA engine -->    <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}" />    <!-- <bean class="org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}"/> -->   </property>   <property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml" />  </bean>  <bean id="entityManagerFactory2"   class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">   <property name="dataSource" ref="dataSource" />   <property name="persistenceUnitName" value="teacher" />      <property name="jpaVendorAdapter">    <!-- Use Hibernate as JPA engine -->    <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}" />    <!-- <bean class="org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter"     p:database="${jpa.database}" p:showSql="${jpa.showSql}"/> -->   </property>   <property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml" />  </bean>

각 jpaStudentDao.java 와 jpaTeacherDao.java 에 아래와 같이 (uniName =" ") 을 구분하여 지정하여 해결했다!

@Repository("studentDao") public class JpaStudentDao implements StudentDao {       @PersistenceContext(unitName ="student")     private EntityManager entityManager;     @Transactional     public void store(Student student) {         entityManager.merge(student);     }

@Repository("teacherDao") public class jpaTeacherDao implements TeacherDao {    @PersistenceContext(unitName ="teacher")     private EntityManager entityManager;     @Transactional     public void store(Teacher teacher) {         entityManager.merge(teacher);     }