我正在尝试从注入(inject)的 EntityManager 中解包 Hibernate Session，因为我需要使用 Hibernate 的 native Criteria API。

当我尝试使用 Criteria 时出现以下异常:

Caused by: java.lang.IllegalStateException: No transactional EntityManager available
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:224)
at com.sun.proxy.$Proxy28.unwrap(Unknown Source)
at sk.uniba.ais2.fajr.dao.impl.PouzivatelDAOHibernate.findByLogin(PouzivatelDAOHibernate.java:22)
at sk.uniba.ais2.fajr.bo.PouzivatelService.findByLogin(PouzivatelService.java:20)
at sk.uniba.ais2.fajr.mvc.controller.FooController.getFoooFOO(FooController.java:38)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:690)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:945)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
... 62 more

但是，当我使用 EntityManager 本身的查询 api 时，一切正常。

我的配置:

db.xml

    <?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:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    default-autowire="byName" xmlns:jpa="http://www.springframework.org/schema/data/jpa"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-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/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <!-- Scans within the base package of the application for @Components to 
        configure as beans -->
    <bean id="placeholderConfig"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location" value="classpath:db.properties" />
    </bean>

    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
    destroy-method="close">
    <property name="driverClass" value="${db.driver}" />
    <property name="jdbcUrl" value="${db.url}" />
    <property name="user" value="${db.username}" />
    <property name="password" value="${db.password}" />
</bean>

    <bean id="jpaVendorAdapter"
        class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
        <property name="showSql" value="true" />
        <property name="database" value="ORACLE" />
    </bean>

    <bean id="entityManagerFactory"
        class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="jpaVendorAdapter" ref="jpaVendorAdapter" />
        <property name="packagesToScan" value="sk.uniba.ais2.fajr.entities" />
        <property name="jpaPropertyMap">
            <map>
                <entry key="hibernate.default_schema" value="AIS2" />
            </map>
        </property>

    </bean>

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>

    <tx:annotation-driven transaction-manager="transactionManager"
        proxy-target-class="true" />
    <jpa:repositories base-package="sk.uniba.ais2.fajr.dao" />
</beans>

PouzivatelDAOHibernate 不起作用:

    @Repository
public class PouzivatelDAOHibernate implements PouzivatelDAO {

    @PersistenceContext
    private EntityManager entityManager;

    @Override
    public Pouzivatel findByLogin(String login) {
        Criteria criteria = entityManager.unwrap(Session.class).createCriteria(Pouzivatel.class);
        return (Pouzivatel) criteria.add(Restrictions.eq("login", login)).uniqueResult();
    }

}

确实有效的 PouzivatelDAOHibernate:

@Repository
public class PouzivatelDAOHibernate implements PouzivatelDAO {

    @PersistenceContext
    private EntityManager entityManager;

    @Override
    public Pouzivatel findByLogin(String login) {
//      Criteria criteria = entityManager.unwrap(Session.class).createCriteria(Pouzivatel.class);
//      return (Pouzivatel) criteria.add(Restrictions.eq("login", login)).uniqueResult();
        Query query = entityManager.createQuery("select p from Pouzivatel p where login=?");
        query.setParameter(1, login);
        return (Pouzivatel) query.getSingleResult();
    }

}

编辑:我正在使用 Spring Data JPA

最佳答案

我实际上已经解决了这个问题(解决方案非常简单):使用 org.springframework.transaction.annotation.Transactional 而不是 javax.transaction.Transactional

关于java - 没有可用的事务性 EntityManager - 使用 JPA Api，Hibernate Session 出错，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/22382950/