java - 使用 getCurrentSession() 时出现 "No Session found for current thread"异常

Question

我正在使用 Spring MVC 4.0.6 和 Hibernate 4.3.5 。我正在尝试将值插入到我的数据库表中，但收到此错误消息:

HTTP 状态 500 - 请求处理失败；嵌套异常是 org.hibernate.HibernateException: 没有为当前线程找到 session

目前我正在使用 sessionFactory.getCurrentSession() 来保存我的数据，但如果我使用 getSessionFactory().openSession(); 它可以正常工作。我听说我应该使用 getCurrentSession 而不是 getSessionFactory().openSession(); 因为它会在我每次进行数据库查询时创建一个新 session 。

您能否查看下面的代码并告诉我我做错了什么以及如何让 sessionFactory.getCurrentSession() 工作？

GradeServiceImpl:

@Service
@Transactional
public class GradeServiceImpl implements GradeService {

 @Autowired
 private GradeDao gradeDao;

 @Override
 public void addGrade(Grade grade) {

    gradeDao.addGrade(grade);
 }
}

GradeDaoImpl

@Repository
@Transactional
public class GradeDaoImpl implements GradeDao {

 @Autowired
 private SessionFactory sessionFactory;

 public SessionFactory getSessionFactory() {
    return sessionFactory;
 }

 public void setSessionFactory(SessionFactory sessionFactory) {
    this.sessionFactory = sessionFactory;
 }
 @Override
 public void addGrade(Grade grade) {

    sessionFactory.getCurrentSession().save(grade);

 }
}  

servlet-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns:beans="http://www.springframework.org/schema/beans" xmlns="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd   http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd   http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

   <annotation-driven />
   <context:annotation-config />
   <context:component-scan base-package="com.spring" />


   <resources mapping="/resources/**" location="/resources/" />
   <!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
   <beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
      <beans:property name="prefix" value="/WEB-INF/views/" />
      <beans:property name="suffix" value=".jsp" />
   </beans:bean>

   <beans:bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource" destroy-method="close">
      <beans:property name="driverClassName" value="com.mysql.jdbc.Driver" />
      <beans:property name="url" value="jdbc:mysql://localhost:3306/java" />
      <beans:property name="username" value="root" />
      <beans:property name="password" value="" />
   </beans:bean>

   <beans:bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
      <beans:property name="basename" value="resources/messages" />
      <beans:property name="defaultEncoding" value="UTF-8" />
   </beans:bean>

   <beans:bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
      <beans:property name="dataSource" ref="dataSource" />
      <!-- <beans:property name="configLocation">
        <beans:value>classpath:hibernate.cfg.xml</beans:value>
        </beans:property>    -->
      <beans:property name="packagesToScan" value="com.spring" />
      <beans:property name="hibernateProperties">
         <beans:props>
            <beans:prop key="dialect">org.hibernate.dialect.MySQLDialect</beans:prop>
            <beans:prop key="show_sql">true</beans:prop>
            <beans:prop key="hibernate.hbm2ddl.auto">create</beans:prop>
            <beans:prop key="hibernate.show_sql">true</beans:prop>
         </beans:props>
      </beans:property>
   </beans:bean>

   <beans:bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
      <beans:property name="sessionFactory" ref="sessionFactory" />
   </beans:bean>

</beans:beans>

Web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.5" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
   <!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
   <context-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/spring/root-context.xml</param-value>
   </context-param>
   <!-- Creates the Spring Container shared by all Servlets and Filters -->
   <listener>
      <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
   </listener>
   <!-- Processes application requests -->
   <servlet>
      <servlet-name>appServlet</servlet-name>
      <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
      <init-param>
         <param-name>contextConfigLocation</param-name>
         <param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
      </init-param>
      <load-on-startup>1</load-on-startup>
   </servlet>
   <servlet-mapping>
      <servlet-name>appServlet</servlet-name>
      <url-pattern>/</url-pattern>
   </servlet-mapping>
</web-app>

更新 - 堆栈跟踪

异常

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.hibernate.HibernateException: No Session found for current thread
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:973)
    org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

根本原因

org.hibernate.HibernateException: No Session found for current thread
    org.springframework.orm.hibernate4.SpringSessionContext.currentSession(SpringSessionContext.java:106)
    org.hibernate.internal.SessionFactoryImpl.getCurrentSession(SessionFactoryImpl.java:1014)
    com.spring.org.dao.GradeDaoImpl.addGrade(GradeDaoImpl.java:33)
    com.spring.org.service.GradeServiceImpl.addGrade(GradeServiceImpl.java:25)
    com.spring.org.GradeController.saveGrade(GradeController.java:32)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    java.lang.reflect.Method.invoke(Unknown Source)
    org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
    org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
    org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689)
    org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:863)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

Answer 1

正如 Narmer 所说，您将所有数据库配置放在 servlet-context.xml 中什么时候应该进入 root-context.xml 。但问题的真正原因(或其症状)是您没有使用事务代理，如 stacktrace 中所示:GradeController.saveGrade直接调用GradeServiceImpl.addGrade进而直接调用 GradeDaoImpl.addGrade .

通常，您应该输入 @Transactional注解仅在服务层，而不是在 dao 层(只有一个事务层)。并且您应该验证是否从 Controller 自动连接服务为

@Autowired
private GradeService gradeService;

请尝试仅使用一个事务层，并说明堆栈跟踪是否显示事务代理使用情况。

编辑:

您的配置中还有另一个问题:您没有 <tx:annotation-driven/>标签，当需要spring正确处理时@Transactional注释。