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我正在嘗試JPA/Hibernate和Spring。我有一個控制器 - >服務 - > DAO結構，我有一些問題JPA。我認爲它的交易相關，但找不到問題。從DAO回來時的Spring/JPA分離的實體
我有@Service和@Transactional註解的服務。我有一個「removeAll（）」方法，我首先調用「findAll」，然後迭代列表以在實體上調用「remove（）」。當我調用remove方法時，出現「非法參數異常：刪除分離的實例」。
從我的紅色，我應該只將@Transactional註釋放在我的服務類上，我的DAO應該以某種方式加入事務。如果我把所有@Transaction的東西放在DAO類上，一切正常。但是我記得，我應該只需要服務類的註釋。可能存在配置問題，但無法找到它。
所以，如果有人可以看看，也許你會馬上看到它。
這裏我的服務類的代碼片段：
@Service("courseService")
@Transactional
public class CourseServiceImpl implements CourseService {
@Autowired
@Qualifier("courseTemplateDAO")
private CourseTemplateDAO courseTemplateDAO;
public Integer removeAllTemplates() {
int removed = 0;
List<CourseTemplate> courseTemplates = getCourseTemplateDAO().findAll();
for (CourseTemplate currCourseTemplate : courseTemplates) {
getCourseTemplateDAO().remove(currCourseTemplate);
removed++;
}
return removed;
}
public CourseTemplateDAO getCourseTemplateDAO() {
return courseTemplateDAO;
}
public void setCourseTemplateDAO(CourseTemplateDAO courseTemplateDAO) {
this.courseTemplateDAO = courseTemplateDAO;
}
}
泛型DAO類，非常標準：
public abstract class JPADAOImpl<T> extends JpaDaoSupport implements JPADAO<T> {
private Class<T> entityClass;
public JPADAOImpl() {
ParameterizedType genericSuperclass = (ParameterizedType) getClass().getGenericSuperclass();
this.entityClass = (Class<T>) genericSuperclass.getActualTypeArguments()[0];
}
public void persist(T entity) {
getJpaTemplate().persist(entity);
}
public void remove(T entity) {
getJpaTemplate().remove(entity);
}
public T merge(T entity) {
return getJpaTemplate().merge(entity);
}
public void refresh(T entity) {
getJpaTemplate().refresh(entity);
}
public T flush(T entity) {
getJpaTemplate().flush();
return entity;
}
public T findById(long id) {
return getJpaTemplate().find(entityClass, id);
}
public List<T> findAll() {
List<T> res = getJpaTemplate().execute(new JpaCallback<List<T>>() {
public List<T> doInJpa(EntityManager em) throws PersistenceException {
Query q = em.createQuery("SELECT h FROM " + entityClass.getName() + " h");
return q.getResultList();
}
});
return (List<T>) res;
}
public Integer removeAll() {
return getJpaTemplate().execute(new JpaCallback<Integer>() {
public Integer doInJpa(EntityManager em) throws PersistenceException {
Query q = em.createQuery("DELETE FROM " + entityClass.getName() + " h");
return q.executeUpdate();
}
});
}
public Class<T> getEntityClass() {
return entityClass;
}
}
而且我CourseTemplateDAO實現類：
@Repository("courseTemplateDAO")
public class CourseTemplateDAOImpl extends JPADAOImpl<CourseTemplate> implements CourseTemplateDAO {
@Autowired
private EntityManagerFactory entityManagerFactory;
public CourseTemplateDAOImpl() {
}
@PostConstruct
public void init() {
super.setEntityManagerFactory(entityManagerFactory);
}
}
我的春天應用程序上下文配置文件：
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context"
xmlns:jee="http://www.springframework.org/schema/jee" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd">
<context:annotation-config />
<context:component-scan base-package="org.ksshi"/>
<tx:annotation-driven transaction-manager="transactionManager"/>
<bean class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean" id="entityManagerFactory">
<property name="persistenceUnitName" value="KSSHIPersistenceUnit"/>
</bean>
<bean class="org.springframework.orm.jpa.JpaTransactionManager" id="transactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>
<bean id="messageSource" class="org.ksshi.service.i18n.impl.I18NMessageSource"/>
最後，我的持久性配置文件：
<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_2_0.xsd"
version="2.0">
<persistence-unit name="KSSHIPersistenceUnit" transaction-type="RESOURCE_LOCAL">
<description>
Persistence unit for the KSSHI application
</description>
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>org.ksshi.entity.CourseTemplate</class>
<class>other classes</class>
<properties>
<property name="hibernate.hbm2ddl.auto" value="update"/>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>
<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/ksshi"/>
<property name="hibernate.connection.username" value="sa"/>
<property name="hibernate.connection.password" value=""/>
<property name="hibernate.c3p0.min_size" value="5"/>
<property name="hibernate.c3p0.max_size" value="20"/>
<property name="hibernate.c3p0.timeout" value="300"/>
<property name="hibernate.c3p0.max_statements" value="50"/>
<property name="hibernate.c3p0.idle_test_period" value="3000"/>
</properties>
</persistence-unit>