Spring-没有EntityManager可以用于当前线程的实际事务处理-无法可靠地处理“持久”调用

Question

当尝试调用“ persist”方法将实体模型保存到Spring MVC
Web应用程序中的数据库时，出现此错误。在Internet上找不到与该特定错误相关的任何帖子或页面。似乎似乎EntityManagerFactory
bean出了点问题，但是我对Spring编程还是比较陌生，所以对我来说，似乎一切都已初始化好，并且根据Web上的各种教程文章。

dispatcher-servlet.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:jpa="http://www.springframework.org/schema/data/jpa"
xsi:schemaLocation="
 http://www.springframework.org/schema/mvc 
 http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
 http://www.springframework.org/schema/beans 
 http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
 http://www.springframework.org/schema/context 
  http://www.springframework.org/schema/context/spring-context-4.0.xsd
  http://www.springframework.org/schema/jdbc
  http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.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/data/repository
  http://www.springframework.org/schema/data/repository/spring-repository-1.5.xsd
  http://www.springframework.org/schema/jee
  http://www.springframework.org/schema/jee/spring-jee-3.2.xsd">

    <context:component-scan base-package="wymysl.Controllers" />
    <jpa:repositories base-package="wymysl.repositories"/> 
    <context:component-scan base-package="wymysl.beans" /> 
    <context:component-scan base-package="wymysl.Validators" /> 
    <bean
     class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />
     <bean class="org.springframework.orm.hibernate4.HibernateExceptionTranslator"/>

     <bean id="passwordValidator" class="wymysl.Validators.PasswordValidator"></bean>

     <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">

        <property name="driverClassName" value="oracle.jdbc.driver.OracleDriver" />
        <property name="url" value="jdbc:oracle:thin:@localhost:1521:xe" />
        <property name="username" value="system" />
        <property name="password" value="polskabieda1" />
    </bean>

 <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="persistenceXmlLocation" value="classpath:./META-INF/persistence.xml" />
    <property name="dataSource" ref="dataSource" />

    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
            <property name="databasePlatform" value="org.hibernate.dialect.H2Dialect" />
            <property name="showSql" value="true" />
            <property name="generateDdl" value="false" />
        </bean>
    </property>
    <property name="jpaProperties">
        <props>
            <prop key="hibernate.max_fetch_depth">3</prop>
            <prop key="hibernate.jdbc.fetch_size">50</prop>
            <prop key="hibernate.jdbc.batch_size">10</prop>
        </props>
    </property>
</bean>

    <mvc:annotation-driven />

    <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
    <property name="basename" value="classpath:messages" />
</bean>

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


    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix">
        <value>/WEB-INF/jsp/</value>
    </property>
    <property name="suffix">
        <value>.jsp</value>
    </property>
</bean>

    <mvc:resources mapping="/resources/**" location="/resources/" />
    <mvc:resources mapping="/resources/*" location="/resources/css/"  
    cache-period="31556926"/>



</beans>

RegisterController.java

@Controller
public class RegisterController {

    @PersistenceContext
    EntityManager entityManager;

    @Autowired
    PasswordValidator passwordValidator;

    @InitBinder
    private void initBinder(WebDataBinder binder) {
        binder.setValidator(passwordValidator);
    }

    @RequestMapping(value = "/addUser", method = RequestMethod.GET)
    public String register(Person person) {


        return "register";

    }

    @RequestMapping(value = "/addUser", method = RequestMethod.POST)
    public String register(@ModelAttribute("person") @Valid @Validated Person person, BindingResult result) {
        if(result.hasErrors()) {
            return "register";
        } else {
            entityManager.persist(person);
            return "index";

        }




    }

Answer 1

我遇到了同样的问题，并为该方法添加了注释，@Transactional并且该方法有效。

更新：检查spring文档，默认情况下PersistenceContext看起来是Transaction类型的，因此这就是为什么该方法必须是事务性的（http://docs.spring.io/spring/docs/current/spring-
framework-reference/ html /
orm.html
）：

@PersistenceContext批注具有可选的属性类型，默认为PersistenceContextType.TRANSACTION。此默认设置是您需要接收共享的EntityManager代理的条件。替代方案PersistenceContextType.EXTENDED是完全不同的事情：这导致所谓的扩展EntityManager，它不是线程安全的，因此不能在并发访问的组件（例如Spring管理的Singleton
bean）中使用。扩展的EntityManager仅应用于有状态的组件（例如，驻留在会话中），并且EntityManager的生命周期不依赖于当前事务，而完全取决于应用程序。