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Spring，Hibernate-多对多-LazyInitializationException（springboot多对多关系怎么写）

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在本文中，我们将为您详细介绍Spring，Hibernate-多对多-LazyInitializationException的相关知识，并且为您解答关于springboot多对多关系怎么写的疑问，此外

在本文中，我们将为您详细介绍Spring，Hibernate-多对多-LazyInitializationException的相关知识，并且为您解答关于springboot多对多关系怎么写的疑问，此外，我们还会提供一些关于c# – NHibernate.LazyInitializationException、hibernate clear() 误用 与 LazyInitializationException： could not initialize proxy - no Session、Hibernate org.hibernate.LazyInitializationException：无法延迟初始化角色集合：、hibernate – 在@Transactional方法中的LazyInitializationException的有用信息。

本文目录一览：

Spring，Hibernate-多对多-LazyInitializationException（springboot多对多关系怎么写）

Spring，Hibernate-多对多-LazyInitializationException（springboot多对多关系怎么写）

我有2个模型。

用户：

    @Entitypublic class User implements Serializable {    Long id;    String name;    List<Car> cars;    public User() {    }    public Long getId() {        return id;    }    public void setId(Long id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public List<Car> getCars() {        return cars;    }    public void setCars(List<Car> cars) {        this.cars = cars;    }}

汽车：

@Entitypublic class Car implements Serializable {Long id;String mark;public Car() {}public Long getId() {    return id;}public void setId(Long id) {    this.id = id;}public String getMark() {    return mark;}public void setMark(String mark) {    this.mark = mark;}}

贴图：

用户：

    <hibernate-mapping><class name="com.bontade.phone_book.mvc.spring.models.User" table="USERS">    <id name="id" type="java.lang.Long">    <column name="ID" />    <generator/>    </id>            <property name="name" not-null="true" length="100" type="java.lang.String">    <column name="NAME" />    </property>           <list name="cars" table="USER_CAR" cascade="all">    <key>        <column name="USER_ID" />    </key>    <list-index></list-index>    <many-to-many column="CAR_ID"/>    </list>        </class></hibernate-mapping>

汽车：

    <hibernate-mapping><class name="com.bontade.phone_book.mvc.spring.models.Car" table="CARS">    <id name="id" type="java.lang.Long">    <column name="ID" />    <generator/>    </id>    <property name="mark"  not-null="true" length="20" type="java.lang.String">    <column name="MARK" />    </property>     </class></hibernate-mapping>

HomePageController：

public class HomePageController extends AbstractController {private UserDAO userDAO;private CarDAO carDAO;@Overrideprotected ModelAndView handleRequestInternal(HttpServletRequest request,        HttpServletResponse response) throws Exception {            Car markCar = new Car();    markCar.setId(null);    markCar.setMark("111");    carDAO.saveCar(markCar);    User mark = new User();    mark.setId(null);    mark.setName("mark");    List a = new ArrayList<Car>();    a.add(markCar);    mark.setCars(a);    userDAO.saveUser(mark);    List<User> users = userDAO.getAll();    System.out.println("==" + users.size() + "===");    System.out.println(users.get(0).getCars().get(0).getMark());    ...}...}

但是当我执行line时：

System.out.println(users.get(0).getCars().get(0).getMark());

以下堆栈跟踪出现错误：

        Hibernate: select user0_.ID as ID0_, user0_.NAME as NAME0_ from USERS user0_==1==2011-02-23 17:35:10 org.apache.catalina.core.StandardWrapperValve invokeSEVERE: Servlet.service() for servlet [dispatcher] in context with path [/PhoneBook] threw exception [Request processing failed; nested exception is org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.bontade.phone_book.mvc.spring.models.User.cars, no session or session was closed] with root causeorg.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.bontade.phone_book.mvc.spring.models.User.cars, no session or session was closed    at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380)    at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372)    at org.hibernate.collection.AbstractPersistentCollection.readElementByIndex(AbstractPersistentCollection.java:173)    at org.hibernate.collection.PersistentList.get(PersistentList.java:293)    at com.bontade.phone_book.mvc.spring.controllers.HomePageController.handleRequestInternal(HomePageController.java:59)    at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:153)    at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:48)    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:875)    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:807)    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:571)    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:501)    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:306)    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:244)    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:108)    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:558)    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:379)    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:243)    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:259)    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:281)    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)    at java.lang.Thread.run(Thread.java:662)

我是否构造了错误的映射文件，尤其是多对多关系？

答案1

小编典典

默认情况下，Hibernate将延迟加载集合。换句话说，除非绝对需要，否则它不会进入数据库来检索汽车列表。这意味着从您的dao层返回的对象将不会初始化汽车列表，除非您尝试访问它。当您尝试访问它时，您就不再在会话中，因此您会获得异常。

您可以通过在hibernate映射中设置lazy =“ false”来显式禁用该list属性的延迟获取，这将确保在从dao层返回之前填充整个属性。

c# – NHibernate.LazyInitializationException

c# – NHibernate.LazyInitializationException

我们偶尔会出现这个问题,但现在我每次都可以重现它.我在自定义构建的论坛上增加了一个视图计数器,这会导致错误：

NHibernate.LazyInitializationException: Failed to lazily initialize a collection,no session or session was closed

在对象中的另一个集合上发生此错误.如果我添加：

.Not.LazyLoad()

对于我的Fluent映射,错误在我的项目周围移动.我一直禁止对对象的延迟加载,直到它没有延迟加载的地方,然后它抛出了这个错误：

NHibernate.LazyInitializationException: Could not initialize proxy – no Session.

所以,然后我在懒惰的装载上取出了遗嘱,现在我又恢复了原点.当我递增此视图计数器时,它只会出错.这是我的基类保存代码的片段：

using (ISession session = GetSession())
using (ITransaction tx = session.BeginTransaction())
{
       session.SaveOrUpdate(entity);
       tx.Commit();
}

环顾四周,我在另一篇文章中读到这些交易可能会导致问题,但这是因为它们被放置在哪里.此代码扩展到与我的域对象(存储库类)分开的类.这是帖子：

hibernate: LazyInitializationException: could not initialize proxy

我不相信这是我的问题.这是第一个抛出错误的集合的流畅映射.还有其他几个类似的集合.

HasManyToMany(x => x.Votes)
    .WithTableName("PostVotes")
    .WithParentKeyColumn("PostId")
    .WithChildKeyColumn("VoteId");

解决方法

对此问题的进一步研究表明,在单次回调服务器时,如果执行保存并获取,则需要刷新会话.我在保存后进行了冲洗,这似乎纠正了问题.

hibernate clear() 误用 与 LazyInitializationException： could not initialize proxy - no Session

hibernate clear() 误用 与 LazyInitializationException： could not initialize proxy - no Session

最近遇到一个很奇怪的问题。 就是 不知道hibernate 怎么就爆

org.hibernate.LazyInitializationException: could not initialize proxy - no Session
	at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:167)
	at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:215)
	at org.hibernate.engine.ForeignKeys$Nullifier.isNullifiable(ForeignKeys.java:137)
	at org.hibernate.engine.ForeignKeys$Nullifier.nullifyTransientReferences(ForeignKeys.java:92)
	at org.hibernate.engine.ForeignKeys$Nullifier.nullifyTransientReferences(ForeignKeys.java:70)
	at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:311)
	at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:204)
	at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:130)
	at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)
	at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:56)
	at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)
	at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:50)
	at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
	at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:705)
	at org.hibernate.impl.SessionImpl.save(SessionImpl.java:693)
	at org.hibernate.impl.SessionImpl.save(SessionImpl.java:689)
	at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:686)
	at org.springframework.orm.hibernate3.HibernateTemplate$12.doInHibernate(HibernateTemplate.java:683)
	at org.springframework.orm.hibernate3.HibernateTemplate.doExecute(HibernateTemplate.java:406)
	at org.springframework.orm.hibernate3.HibernateTemplate.executeWithNativeSession(HibernateTemplate.java:374)
	at org.springframework.orm.hibernate3.HibernateTemplate.save(HibernateTemplate.java:683)
	at com.moneyP2P.base.spring.service.BaseService.save(BaseService.java:23)
	at com.moneyP2P.base.spring.service.BaseService$$FastClassByCGLIB$$aefff274.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
	at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
	at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
	at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
	at com.rongpd.pay.basedata.service.AllinpayRechargeRecordService$$EnhancerByCGLIB$$f9ebecbe.save(<generated>)
	at com.rongpd.pay.basedata.service.AllinpayTranxManagerService.allinPayRechargeAfterDo(AllinpayTranxManagerService.java:660)
	at com.rongpd.pay.basedata.service.AllinpayTranxManagerService.allinPayRecharge(AllinpayTranxManagerService.java:602)
	at com.rongpd.pay.basedata.service.AllinpayTranxManagerService$$FastClassByCGLIB$$34d49aa4.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
	at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
	at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
	at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
	at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
	at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
	at com.rongpd.pay.basedata.service.AllinpayTranxManagerService$$EnhancerByCGLIB$$63a19e0b.allinPayRecharge(<generated>)
	at com.moneyP2P.p2p.VSFP.mobile.spring.controller.AllinPayMobileController.allinpayPayment(AllinPayMobileController.java:508)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
	at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
	at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
	at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:838)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:230)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)

找不到 hibernate 的 session 的错误？？？ 可是我明明没有 关闭这个 session啊？？

看这个异常是 org.hibernate.LazyInitializationException 懒加载？？ 什么意思啊？ 懒加载 表的其他对象 异常了，差不多了？

那我们可以修改为 急加载？可是 这个方法操作那么多对象，表都改？ 其他地方用不是 都是 急加载了，，，性能啊！！！

那到底是 哪里错问题了呢？

在排除的时候，我是看了好久都没有找到。 有一个 细心的同事 找到了，觉得可能是这个错误：

 public void update(Object obj){
		 dao.clear();// 这里引起的错误
    	dao.update(obj);
    }

注释掉了 这个 clear 就 好了。

分析

开始以为是 hibernate 什么 BUG 什么的呢？ 让人看得不明白。 这个 clear 就是 session.clear() 将缓存清空。 可是想想，将缓存清空就清空了，那么再次查询一次数据库就好了，能有什么问题？

想想看看 上面的 懒加载对象， 和看看代码保存就知道了

.....
rechargesService.update(rechargeToSuccess); //这个里面  update 加了clear 
			// 记录充值成功后相关流水
			rechargesService.rechargeReturn(rechargeToSuccess);

			// 记录快捷支付的充值流水数据
			AllinpayRechargeRecord arRecord = new AllinpayRechargeRecord();
			arRecord.setAccountNo(userBank.getBankAccount());// 卡号
			arRecord.setBanktype(userBank.getBanktype());// 银行类型  ， 清空了缓存导致 这个 userBank 使用 延迟加载 查询 的 Banktype 的时候，由于缓存清空了数据，所以就获取不到懒加载的数据。
// 也就是懒加载错误，
			arRecord.setOrderNum(reqNo);// 充值流水号
			arRecord.setReAccount(tranAmtDecimal);// 实际充值金额以元为单位
			arRecord.setUserbasicsinfo(userBank.getUserbasicsinfo());
.....

也就是说 hibernate的 报错有点不明确，很容易把人搞蒙了，想错了。 所以 clear 清缓存 要慎重啊， hibernate的方法不能乱用啊！！！.

Hibernate org.hibernate.LazyInitializationException：无法延迟初始化角色集合：

Hibernate org.hibernate.LazyInitializationException：无法延迟初始化角色集合：

我有以下提到的实体类，当我执行我的应用程序时，我得到了以下异常。其他一些类似的问题也不能解决问题。

WARNING: StandardWrapperValve[jersey-serlvet]: PWC1406: Servlet.service()for servlet jersey-serlvet threw exceptionorg.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: test.entity.Dept.empDeptno, no sessionor session was closedat org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:393)       at    org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:385)    at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:378)

我该如何解决这个问题？

Emp实体

@Entity@Table(name = "EMP", schema = "SCOTT")@XmlRootElement@NamedQueries({    @NamedQuery(name = "Emp.findAllEmployees", query = "select e from Emp e left     join fetch e.deptNo order by e.empno desc")})public class Emp implements java.io.Serializable {@Id@Column(name = "EMPNO", unique = true, nullable = false, precision = 4,scale = 0)private short empno;@ManyToOne@JoinColumn(name = "DEPTNO", referencedColumnName = "DEPTNO")private Dept deptNo;

部门实体

@Entity@Table(name = "DEPT", schema = "SCOTT")@XmlRootElementpublic class Dept implements java.io.Serializable {@Id@Column(name = "DEPTNO", unique = true, nullable = false, precision = 2,scale = 0)private short deptno;@OneToMany(fetch=FetchType.LAZY,mappedBy = "deptNo")private Set<Emp> empDeptno;

DAOImpl

@Overridepublic List<Emp> findAllEmployees() {  return getEntityManager().createNamedQuery("Emp.findAllEmployees", Emp.class).getResultList();}

泽西岛RESTful服务

 @Component @Path("/employee") public class EmployeeRestService { @Autowired EmployeeService employeeService; @GET @Produces({MediaType.APPLICATION_JSON}) public List<Emp> getEmployees() { List<Emp> emp = new ArrayList<Emp>(); emp.addAll(getEmployeeService().findAllEmployees()); return emp; }

springapplicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"       xmlns:context="http://www.springframework.org/schema/context"       xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.0.xsdhttp://www.springframework.org/schema/txhttp://www.springframework.org/schema/tx/spring-tx-3.0.xsdhttp://www.springframework.org/schema/contexthttp://www.springframework.org/schema/context/spring-context-3.0.xsd">    <!-- Data Source Declaration -->        <bean id="DataSource">        <property name="jndiName" value="jdbc/scottDS"/>       </bean>    <context:component-scan base-package="net.test" />    <bean/>    <bean id="entityManagerFactory">        <property name="dataSource" ref="DataSource" />        <property name="packagesToScan" value="net.test" />        <property name="jpaVendorAdapter">            <bean>                <property name="showSql" value="false" />                <property name="generateDdl" value="false" />                <property name="databasePlatform" value="${jdbc.dialectClass}" />            </bean>        </property>    </bean>    <bean id="defaultLobHandler"/>      <!-- Transaction Config -->    <bean id="transactionManager">        <property name="entityManagerFactory" ref="entityManagerFactory" />    </bean>    <tx:annotation-driven transaction-manager="transactionManager"/>              <context:annotation-config/>    <bean id="hibernateStatisticsMBean">        <property name="statisticsEnabled" value="true" />        <property name="sessionFactory" value="#{entityManagerFactory.sessionFactory}" />    </bean></beans>

答案1

小编典典

我已通过在web.xml中添加以下内容解决了该问题

<filter><filter-name>OpenEntityManagerInViewFilter</filter-name><filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class></filter><filter-mapping><filter-name>OpenEntityManagerInViewFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping>

在这里和这里礼貌

谢谢

hibernate – 在@Transactional方法中的LazyInitializationException

hibernate – 在@Transactional方法中的LazyInitializationException

当我尝试在执行以下操作时尝试访问延迟加载的异常时,我遇到了org.hibernate.LazyInitializationException错误：

@Transactional
public void displayAddresses()
{
     Person person = getPersonByID(1234);
     Liststem.out.println(address.getFullAddress());
}

我的实体看起来像这样：

@Entity
@Table("PERSON_TBL")
public class Person
{
     ...

     @OnetoMany(cascade=CascadeType.ALL,targetEntity=Address.class,mappedBy="person")
     private List

我的印象是,通过使用@Transactional注释在我displayAddresses()方法时,它会保持会话活着直到方法完成,让我访问延迟加载地址的集合.

我错过了什么吗？

编辑

按照Tomasz的建议：在我的displayAddresses()方法中,TransactionSynchronizationManager.isActualTransactionActive()的状态被证明是假的.

这确实缩小了问题范围,但为什么我的交易此时不会有效？

最佳答案
这已经得到了解答,但只是想发布一个替代答案,这个答案在类似情况下对我有用 – 为后代;)

在我的情况下,问题是由于包含延迟加载的集合的实例已被手动驱逐(全部在事务边界内).

关于Spring，Hibernate-多对多-LazyInitializationException和springboot多对多关系怎么写的问题我们已经讲解完毕，感谢您的阅读，如果还想了解更多关于c# – NHibernate.LazyInitializationException、hibernate clear() 误用 与 LazyInitializationException： could not initialize proxy - no Session、Hibernate org.hibernate.LazyInitializationException：无法延迟初始化角色集合：、hibernate – 在@Transactional方法中的LazyInitializationException等相关内容，可以在本站寻找。

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