当传播设置为 Propagation.NOT_SUPPORTED 时 Hibernate 和 TransactionRequiredException

TL;DR:

• 服务方法注释为@Transactional(propagation = Propagation.NOT_SUPPORTED)
• Hibernate 5.0.4.Final：一切按预期工作（方法在没有事务的情况下执行）
• 休眠 5.2.5.最终版：javax.persistence.TransactionRequiredException: no transaction is in progress被抛出
• 作为这个问题的测试用例，我创建了一个简单的 Maven Web 应用程序，代码中所做的唯一更改（从旧工作项目复制粘贴）是 pom.xml 中的 Hibernate 版本冲突

问题：

• 如今，在没有事务的情况下执行服务方法的正确方法是什么？

代码片段（使用Spring作为主要框架）：

DAO:

@Repository
public class UrlDaoImpl implements UrlDao {

    @Autowired
    private SessionFactory sessionFactory;

    @Override
    public List<Url> getAllUrls() {
        Session session = sessionFactory.getCurrentSession();
        Query query = session.createQuery("from Url");
        return query.list();
    }

}

Service:

@Service
public class UrlServiceImpl implements UrlService {

    @Autowired
    private UrlDao urlDao;


    @Override
    @Transactional // THIS WORKS IN NEW HIBERNATE
    public List<Url> getAllUrls() {
        return urlDao.getAllUrls();
    }

    @Override
    @Transactional(propagation = Propagation.NOT_SUPPORTED)  // THIS USED TO WORK BUT NOW THROWS EXCEPTION
    public List<Url> getAllUrlsNoTxn() {
        return urlDao.getAllUrls();
    }

}

控制器：

@Controller
public class HomeController {

    @Autowired
    private UrlService urlService;

    @RequestMapping(value = "/", method = RequestMethod.GET, produces = "text/plain")
    public String entryPoint() {

        urlService.getAllUrls();
        System.out.println("--------------------- ok");
        return "ok";
    }

    @RequestMapping(value = "/no-txn", method = RequestMethod.GET, produces = "text/plain")
    public String entryPointNoTxn() {

        // EXCEPTION WILL BE THROWN BELOW
        urlService.getAllUrlsNoTxn();
        System.out.println("--------------------- ok no txn");
        return "ok no txn";
    }

}

新 Hibernate 中异常的堆栈跟踪：

exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is javax.persistence.TransactionRequiredException: no transaction is in progress
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:982)
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

root cause

javax.persistence.TransactionRequiredException: no transaction is in progress
    org.hibernate.internal.SessionImpl.checkTransactionNeeded(SessionImpl.java:3439)
    org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1410)
    org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1406)
    org.springframework.orm.hibernate5.SessionFactoryUtils.flush(SessionFactoryUtils.java:144)
    org.springframework.orm.hibernate5.SpringSessionSynchronization.beforeCommit(SpringSessionSynchronization.java:95)
    org.springframework.transaction.support.TransactionSynchronizationUtils.triggerBeforeCommit(TransactionSynchronizationUtils.java:95)
    org.springframework.transaction.support.AbstractPlatformTransactionManager.triggerBeforeCommit(AbstractPlatformTransactionManager.java:932)
    org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:744)
    org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:730)
    org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:504)
    org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:292)
    org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
    com.sun.proxy.$Proxy32.getAllUrlsNT(Unknown Source)
    com.example.web.controller.HomeController.entryPointNoTxn(HomeController.java:31)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:498)
    org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220)
    org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134)
    org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
    org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197)
    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)

好吧，经过几个小时的尝试不同的配置（在将这个问题发布到 SO 之前），我终于找到了解决方案。

对于新的 Hibernate 版本，还必须声明另一个必需参数@Transactional如果你想执行一个没有事务的方法：readOnly = true。所以Service部分的工作示例是：

@Service
public class UrlServiceImpl implements UrlService {

    @Autowired
    private UrlDao urlDao;


    @Override
    @Transactional
    public List<Url> getAllUrls() {
        return urlDao.getAllUrls();
    }

    @Override
    @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED)  // ADDED READONLY TO WORK IN NEW HIBERNATE VERSIONS
    public List<Url> getAllUrlsNoTxn() {
        return urlDao.getAllUrls();
    }

}

我还通过调用确认这适用于调试((org.hibernate.engine.transaction.internal.TransactionImpl) session.getTransaction()).isActive();返回true对于第一个服务方法（带有事务）和false对于第二个 Service 方法（使用 Propagation.NOT_SUPPORTED）。