我得到这个错误时,试图调用“持久”方法来保存实体模型到数据库在我的Spring MVC web应用程序。在互联网上找不到任何与这个特定错误有关的帖子或页面。似乎EntityManagerFactory bean有问题,但我对Spring编程相当陌生,所以对我来说,似乎一切都初始化得很好,根据各种教程文章在web。

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";

        }




    }

当前回答

boardRepo.deleteByBoardId (id);

面对同样的问题。transactionrequiredexception:当前线程没有实际事务可用的EntityManager

我通过在控制器/服务上面添加@Transactional注释来解决这个问题。

其他回答

只是一个提示给其他用户搜索这个错误的答案。另一个常见的问题是:

通常不能在同一个类中调用@transactional方法。

(有使用AspectJ的方法和方法,但重构会更容易)

因此,您需要一个调用类和一个保存@transactional方法的类。

您需要将@Transactional添加到方法中

我也犯了同样的错误,因为我从XML配置切换到java配置。

关键是,我没有像Stone Feng建议的那样迁移<tx:annotation-driven/>标记。

因此,我只是在这里添加了@EnableTransactionManagement 在@Configuration类中设置Spring中的注释驱动事务,现在可以工作了

我遇到了同样的问题,我将该方法注释为@Transactional,它工作了。

更新:检查spring文档,默认情况下PersistenceContext是事务类型的,所以这就是为什么方法必须是事务性的(http://docs.spring.io/spring/docs/current/spring-framework-reference/html/orm.html):

The @PersistenceContext annotation has an optional attribute type, which defaults to PersistenceContextType.TRANSACTION. This default is what you need to receive a shared EntityManager proxy. The alternative, PersistenceContextType.EXTENDED, is a completely different affair: This results in a so-called extended EntityManager, which is not thread-safe and hence must not be used in a concurrently accessed component such as a Spring-managed singleton bean. Extended EntityManagers are only supposed to be used in stateful components that, for example, reside in a session, with the lifecycle of the EntityManager not tied to a current transaction but rather being completely up to the application.

当我从同一个组件中的非事务性方法访问一个已经带有事务注释的方法时,我也犯了同样的错误:

Before:
    @Component
    public class MarketObserver {
        @PersistenceContext(unitName = "maindb")
        private EntityManager em;

        @Transactional(value = "txMain", propagation = Propagation.REQUIRES_NEW)
        public void executeQuery() {
          em.persist(....);
        }


        @Async
        public void startObserving() {
          executeQuery(); //<-- Wrong
        }
    }

    //In another bean:
     marketObserver.startObserving();

我通过在自引用组件上调用executeQuery()来修复这个错误:

Fixed version:
    @Component
    public class MarketObserver {
        @PersistenceContext(unitName = "maindb")
        private EntityManager em;

        @Autowired
        private GenericApplicationContext context;

        @Transactional(value = "txMain", propagation = Propagation.REQUIRES_NEW)
        public void executeQuery() {
          em.persist(....);
        }


        @Async
        public void startObserving() {
          context.getBean(MarketObserver.class).executeQuery(); //<-- Works
        }
    }