为什么在使用 Spring OpenEntityManagerInViewFilter 时出现 JPA LazyInitializationException？答案

【问题标题】：Why am I getting JPA LazyInitializationException when using Spring OpenEntityManagerInViewFilter?为什么在使用 Spring OpenEntityManagerInViewFilter 时出现 JPA LazyInitializationException？
【发布时间】：2010-10-19 16:32:33
【问题描述】：

我的 OEIV 过滤器应用似乎没有应用于我的 Struts 操作。我正在使用由 Hibernate 3 支持的 Spring 3、Spring Security 3、Struts2、Tiles2 和 JPA。当我尝试在 struts 操作中访问实体的集合时，除非该实体具有急切的获取类型，否则我将获得 JPA延迟初始化异常。我在堆栈跟踪中看到了过滤器，但不知道为什么它没有被应用。

有人可以帮忙吗？

这是我的 web.xml 过滤器和过滤器映射：

    <!-- Filters -->
<filter>
    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
    <filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
</filter>
<filter>
  <filter-name>springSecurityFilterChain</filter-name>
  <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter>
    <filter-name>struts2</filter-name>
    <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
</filter>
<!-- Filter Mappings -->
  <filter-mapping>
    <filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
<filter-mapping>
      <filter-name>springSecurityFilterChain</filter-name>
      <url-pattern>/*</url-pattern>
</filter-mapping>
<filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

我的实体：

@Entity
@Table(name = "DEALER")

public class Dealer implements Serializable {
    private static final long serialVersionUID = -1831628098752177382L;

    @Id
    @Basic(optional = false)
    @Column(name = "DEALER_ID")
    private Integer id;

    @Basic(optional = false)
    @Column(name = "NAME")
    private String name;
    ...    

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "dealer")
    private Set<InventoryPart> inventoryParts;

    ..getter/setter methods ommitted for brevity
}

导致错误的 Struts 2 Action...

public class DealerAction extends BaseStrutsAction 
implements ModelDriven<Dealer>, Preparable {

public void prepare() throws Exception {
    PermissionedUser user= getAuthenticatedUser();
    if(user != null){
        dealer= user.getDealer();
        if(dealer != null){
            dealerId= dealer.getId();
        }
    }
}
...
public List<InventoryPart> getInventoryParts() {
    inventoryParts= new ArrayList<InventoryPart>(dealer.getInventoryParts());
    return inventoryParts;
}
// other methods ommitted for brevity

}

最后是堆栈跟踪...

    83985 [http-8080-6] ERROR org.hibernate.LazyInitializationException - failed to lazily initialize a collection of role: ...model.Dealer.inventoryParts, no session or session was closed
org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: ...model.Dealer.inventoryParts, 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.initialize(AbstractPersistentCollection.java:365)
    at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:108)
    at org.hibernate.collection.PersistentSet.iterator(PersistentSet.java:186)
    at org.apache.struts2.util.MakeIterator.convert(MakeIterator.java:82)
    at org.apache.struts2.components.IteratorComponent.start(IteratorComponent.java:270)
    at org.apache.struts2.views.jsp.ComponentTagSupport.doStartTag(ComponentTagSupport.java:53)
    at org.apache.jsp.WEB_002dINF.jsp.dealer.list_002dinventory_002dparts_jsp._jspx_meth_s_005fiterator_005f0(list_002dinventory_002dparts_jsp.java:169)
    at org.apache.jsp.WEB_002dINF.jsp.dealer.list_002dinventory_002dparts_jsp._jspService(list_002dinventory_002dparts_jsp.java:121)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:551)
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:488)
    at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:968)
    at org.apache.jasper.runtime.PageContextImpl.doInclude(PageContextImpl.java:650)
    at org.apache.jasper.runtime.PageContextImpl.include(PageContextImpl.java:644)
    at org.apache.tiles.jsp.context.JspTilesRequestContext.include(JspTilesRequestContext.java:103)
    at org.apache.tiles.jsp.context.JspTilesRequestContext.dispatch(JspTilesRequestContext.java:96)
    at org.apache.tiles.renderer.impl.UntypedAttributeRenderer.write(UntypedAttributeRenderer.java:62)
    at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:336)
    at org.apache.tiles.template.InsertAttributeModel.renderAttribute(InsertAttributeModel.java:210)
    at org.apache.tiles.template.InsertAttributeModel.end(InsertAttributeModel.java:126)
    at org.apache.tiles.jsp.taglib.InsertAttributeTag.doTag(InsertAttributeTag.java:311)
    at org.apache.jsp.WEB_002dINF.jsp.fragments.root_jsp._jspx_meth_tiles_005finsertAttribute_005f4(root_jsp.java:291)
    at org.apache.jsp.WEB_002dINF.jsp.fragments.root_jsp._jspService(root_jsp.java:151)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:646)
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:436)
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:374)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:302)
    at org.apache.tiles.servlet.context.ServletTilesRequestContext.forward(ServletTilesRequestContext.java:241)
    at org.apache.tiles.servlet.context.ServletTilesRequestContext.dispatch(ServletTilesRequestContext.java:222)
    at org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44)
    at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:690)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:644)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:627)
    at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:321)
    at org.apache.struts2.views.tiles.TilesResult.doExecute(TilesResult.java:105)
    at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)
    at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:362)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:266)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:50)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:130)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:165)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.LoggingInterceptor.intercept(LoggingInterceptor.java:56)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at ...struts.interceptors.TermsAndConditionsInterceptor.intercept(TermsAndConditionsInterceptor.java:45)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:50)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:165)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at ...struts.interceptors.SpringSecurityInterceptor.intercept(SpringSecurityInterceptor.java:27)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488)
    at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:288)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:95)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:109)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:300)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:133)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter.doFilterInternal(OpenEntityManagerInViewFilter.java:113)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Unknown Source)

感谢任何/所有回复！提前致谢。

修订：添加了 Spring 配置

    <?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:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx" 
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">

    <!-- Persistence Related Beans here -->
    <bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName">
            <value>java:comp/env/jdbc/orcl</value>
        </property>
    </bean>  
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource">
            <ref local="dataSource"/>
        </property>
    </bean>
    <!-- the transactional advice (i.e. what 'happens'; see the <aop:advisor/> bean below) -->
    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <!-- the transactional semantics... -->
        <tx:attributes>
            <!-- all methods starting with 'get' are read-only -->
            <tx:method name="get*" read-only="true" />
            <tx:method name="find*" read-only="true" />
            <tx:method name="load*" read-only="true" />
            <!-- other methods use the default transaction settings (see below) -->
            <tx:method name="*" propagation="REQUIRED" />
        </tx:attributes>
    </tx:advice>
    <!-- Pointcut Expressions For Transaction Advice -->
    <aop:config proxy-target-class="true">
        <aop:pointcut id="txAdvisor" expression="execution(* com.mycompany.mypackage.service.*.*(..))" />
        <aop:advisor advice-ref="txAdvice" pointcut-ref="txAdvisor" />
    </aop:config>

    <!-- Dao Classes -->
    <bean id="dealerDao" class="com.mycompany.mypackage.dao.jpa.DealerDaoImpl"/>
    <bean id="vehicleDao" class="com.mycompany.mypackage.dao.jpa.VehicleDaoImpl"/>
    <bean id="manufacturedPartDao" class="com.mycompany.mypackage.dao.jpa.ManufacturedPartDaoImpl"/>

    <!--  Service Beans -->

    <bean id="dealerService" class="com.mycompany.mypackage.service.impl.DealerServiceImpl">
        <property name="dealerDao" ref="dealerDao"/>
    </bean>

    <bean id="vehicleService" class="com.mycompany.mypackage.service.impl.VehicleServiceImpl">
        <property name="vehicleDao" ref="vehicleDao"/>
    </bean>

    <bean id="manufacturedPartService" class="com.mycompany.mypackage.service.impl.ManufacturedPartServiceImpl">
        <property name="manufacturedPartDao" ref="manufacturedPartDao"/>
        <property name="dealerDao" ref="dealerDao"/>
    </bean>

已修订：这是将经销商对象设置为许可用户的位置：

public class PermissionedUserContextMapperImpl implements
    UserDetailsContextMapper, PermissionedUserContextMapper {

private UserDao userDao;
private DealerService dealerService;

public UserDetails mapUserFromContext(DirContextOperations context,
        String userName, Collection<GrantedAuthority> authorites) {

    PermissionedUser user = userDao.getUser(userName);
    if (user != null && (user.getUserId() != null)) {
        user.setAuthorities((List<GrantedAuthority>) authorites);
        userDao.setLastLoginDate(new Long(user.getUserId()));
        // Find if user is a dealer.
        Long userId= new Long(user.getUserId());
        Dealer dealer = userDao.getDealerForUser(userId);
        if (dealer.getId() != null) {
            // this is a temporary hack because the JPA ORM is not tied to
            // the
            // User/Group structure.
            Dealer jpaManagedDealer = dealerService.getDealer(dealer.getId());
            user.setDealer(jpaManagedDealer);
        }
    }

    return user;
}
...

}

也在 Struts Action 中...

public class DealerAdminAction extends BaseStrutsAction implements ModelDriven<Dealer>, Preparable {

private static final long serialVersionUID = -5848040074874790864L;
private DealerService dealerService;
private Dealer dealer;
private Integer id;

public Integer getId() {
    return id;
}
public void setId(Integer id) {
    this.id = id;
}

public void prepare() throws Exception {
    if(id == null || id.intValue() == 0){
        dealer= new Dealer();
    }else{
        dealer= dealerService.getDealer(id);
    }
}

@SkipValidation
public String getView() throws Exception {
    PermissionedUser user= getAuthenticatedUser();
    if(! user.isADealer()){
        user.setDealer(dealer);
    }
    return SUCCESS;
}

public Dealer getModel() {
    return dealer;
}
...

}

重构代码解决了 LazyInitializationException：

public class DealerAdminAction ... {

    ...        
    @Override
    @SkipValidation
    public String execute() throws Exception {
        return SUCCESS;
    }

    public Dealer getModel() {
        return dealer;
    }

    public void prepare() throws Exception {
        if(id == null || id.intValue() == 0){
            dealer= new Dealer();
        }else{
            dealer= dealerService.getDealer(id);
            PermissionedUser user= getAuthenticatedUser();
            if(! user.isADealer()){
                user.setDealer(dealer);
            }
        }
    }
    ...
}

【问题讨论】：

向我们展示您的 Spring 配置。我不认为你的行为是交易性的
在上面的原始问题中添加了 Spring Config。

标签： spring struts entity lazy-loading

【解决方案1】：

getAuthenticatedUser() 是否有可能返回一个分离的用户对象？然后，当您执行 user.getDealer() 时，经销商对象也将被分离，从而导致延迟加载异常。

【讨论】：

也许吧。用户对象不是 JPA 管理的对象，它是 JDBC 管理的。当用户对象设置了经销商对象时，有 2 个地方。一个在spring UserDetailsContextMapper中，另一个在struts action中。当经销商登录时，他们的经销商对象被设置到允许的用户中，这样就不必检索它，并且可以用来将查询限制在他们的数据中。当系统管理员登录时，系统管理员从列表中选择要管理的经销商，我将经销商对象设置为用户，以便我可以重用工件。见添加。上面的代码
好的，所以 LazyInitializationException 仅在 struts 操作中将经销商对象设置到 PermissionedUser 对象时发生，而不是在 UserDetailsContextMapper 中将经销商设置到 PermissionedUser 时发生。所以，这开始看起来像是正确的答案。为什么对象会在struts对象中分离？是不是因为我的struts方法是get*，而且是applicationContext.xml文件中的只读事务？
好吧，这个问题在某种程度上与交易有关，所以我想我并不像我希望的那样理解这一点。在我的原始代码中，问题只出现在 struts 动作中。通过使用 struts Prepareable 拦截器和 paramsPrepareParamsStack，我在 prepare 方法中检索经销商，并以不同的方法将经销商设置给用户。当我移动方法调用以在同一事务方法中将经销商设置为用户对象时，LazyInitializationException 消失了。上面发布的重构工作代码。

【解决方案2】：

在 web.xml 中添加过滤器

    <filter>
    <filter-name>OpenEntityManagerInViewFilter</filter-name>
    <filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
    <init-param>
        <param-name>entityManagerFactory</param-name>
        <param-value>persistence.EntityManagerFactory</param-value>
    </init-param>
</filter>

<filter-mapping>
    <filter-name>OpenEntityManagerInViewFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

entityManagerFactoryBeanName 参数应与 Spring Framework 配置（在 application-context.xml 中）中的实体管理器工厂 bean 的名称匹配。

【讨论】：

【解决方案3】：

这似乎是您的事务范围的问题。在 Hibernate / JPA 中，一对多引用默认是惰性的。这意味着集合中的实体在被访问之前不会被检索到。只能在加载父对象的同一事务中访问延迟加载的值。

在您的情况下，您在prepare() 方法中检索Dealer 的实例，但您在操作的不同方法中访问inventoryParts。这里的上下文太少了，但很可能这两件事发生在不同的事务中，导致LazyInitializationException。

您可以查看您的事务传播或采取不同的方法访问inventoryParts，例如添加lazy = false，如下所示：

@OneToMany(cascade = CascadeType.ALL, mappedBy = "dealer", lazy = false)
private Set<InventoryPart> inventoryParts;

这可能不是您想要的，因为它总是加载与Dealer 关联的所有InvertoryParts。您还可以通过在prepare() 方法中访问该集合来确保您在同一事务中访问该集合。

只是一些不同的方法。这里没有最佳答案，因为您的表现可能会受到威胁。

【讨论】：

这并不完全准确。访问延迟加载的关联只需要一个活动的 EntityManager，这是在此处使用 OEIV 的要点（只要您有一个活动的 EntityManager，延迟关联可以在另一个事务中加载，而不是用于加载父级的事务）。
我也是这么理解的。 OEIV 旨在专门解决这个问题，所以我遇到了某种配置问题......
你说得对，我忽略了 OEIV 部分，这对问题非常重要......对不起！