0

首先一些信息：

  • 我在用着：
    • Spring 3.1.1.RELEASE
    • 休眠 4.1.5.SP1
    • JSF 2.0？
    • OpenSessionInViewFilter (org.springframework.orm.hibernate4.support.OpenSessionInViewFilter)
    • PrimeFaces 3.3.1
    • 龙目岛 0.11.2
    • JBoss 7.1.1.Final

简短版本：

当我的实体Emloyee变得分离时（因此它也急切地获取了Locations 的集合），我不能在Employee.getLocations().add()没有得到LazyInitializationException. 使用基于非 JPA 的集合作为传输对象是可行的。

长版：

我有一个包含 sEmployee集合的实体Location：

@Data
@EqualsAndHashCode(callSuper = true, of = {})
@ToString(callSuper = true, of = {})
@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public class Employee extends Person
{
    @ManyToMany
    @JoinTable(name = "location_employee",
            joinColumns = @JoinColumn(name = "employee_id",
                    referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "location_id",
                    referencedColumnName = "id"))
    private Set<Location>   locations   = new HashSet<Location>();
}

Employeeextends from Personwhich 有一些字符串，如名称等，但这些不相关。

@Data
@EqualsAndHashCode(of = "id")
@ToString(of = { "id", "name" })
@Entity
@Inheritance(strategy = InheritanceType.JOINED)
public class Person
{
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Setter(AccessLevel.NONE)
    private Long    id;

    private String  name;
}

这个Location类也很简单：

@Data
@EqualsAndHashCode(of = "id")
@ToString(of = { "id", "name" })
@Entity
public class Location
{
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Setter(AccessLevel.NONE)
    private Long            id;

    private String          name;
    @ManyToMany
    @JoinTable(name = "location_employee",
            joinColumns = @JoinColumn(name = "location_id",
                    referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "employee_id",
                    referencedColumnName = "id"))
    private Set<Employee>   employees = new HashSet<Employee>();
}

默认情况下，所有集合都是惰性的。但是在我的 JSF 页面中，我想将Locations 添加到现有的Employee. 为此，我渴望Employee使用以下支持 bean 加载我的内容：

@Named
@Scope("view")
public class BackingBean
{
    @Inject
    private EmployeeDAO employeeDAO;
    private Employee        employeeFull;
    @Inject
    private LocationDAO locationDAO;
    private List<Location> locations;

    public Employee getSelectedEmployeeFull()
    {
        if (selectedEmployeeFull == null)
        {
            selectedEmployeeFull = employeeDAO.getEagerById(1L);
        }
        return selectedEmployeeFull;
    }

    public void setEmployeeFull(Employee e)
    {
        employeeFull = e;
    }

    public List<Location> getLocations()
    {
        if (locations == null)
        {
            locations = locationDAO.getAll()
        }
        return locations;
    }

    //...
}

EmployeeDAO包含急切加载查询的类：

@Named
public class EmployeeDAO
{
    @Inject
    private SessionFactory sessionFactory;

    @Transactional(readOnly = true)
    public Employee getEager(Long id)
    {
        Query q = sessionFactory.getCurrentSession().createQuery("select e from Employee e join fetch e.locations where e.id = :id");
        q.setParameter("id", id);
        try
        {
            return (Employee) q.uniqueResult();
        }
        catch (NonUniqueObjectException ex)
        {
            //Exception logging/handling
            return null;
        }
    }
}

在我的 JSF 中，我有以下代码段：

<p:dialog dynamic="true">
    <h:form>
        <p:selectCheckboxMenu label="Locations" value="#{employeeBean.employeeFull.locations}">
            <f:selectItems var="location" itemLabel="#{location.name}" value="#{employeeBean.locations}" />
        </p:selectCheckboxMenu>

        <p:commandButton value="save" action="#{employeeBean.update}"/>
    </h:form>
</p:dialog>

当我打开对话框时，它会很好地加载属性，并用semployeeFull填充并标记已经拥有的s 。selectCheckboxMenuLocationLocationEmployee

但是，当我单击保存按钮（不更改任何内容）并提交表单时，Employee.locations集合会出现LazyInitializationException：

09:36:42,633 WARNING [javax.enterprise.resource.webcontainer.jsf.lifecycle] (http-localhost-127.0.0.1-8080-1) failed to lazily initialize a collection, no session or session was closed: org.hibernate.LazyInitializationException: failed to lazily initialize a collection, no session or session was closed
    at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:394) [hibernate-core-4.1.5.SP1.jar:4.1.5.SP1]
    at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:386) [hibernate-core-4.1.5.SP1.jar:4.1.5.SP1]
    at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:379) [hibernate-core-4.1.5.SP1.jar:4.1.5.SP1]
    at org.hibernate.collection.internal.PersistentSet.add(PersistentSet.java:206) [hibernate-core-4.1.5.SP1.jar:4.1.5.SP1]
    at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValuesForModel(MenuRenderer.java:382) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValue(MenuRenderer.java:129) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:315) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at org.primefaces.component.selectcheckboxmenu.SelectCheckboxMenuRenderer.getConvertedValue(SelectCheckboxMenuRenderer.java:34) [primefaces-3.3.1.jar:]
    at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1030) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIInput.validate(UIInput.java:960) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIInput.executeValidate(UIInput.java:1233) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIInput.processValidators(UIInput.java:698) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIForm.processValidators(UIForm.java:253) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at org.primefaces.component.dialog.Dialog.processValidators(Dialog.java:359) [primefaces-3.3.1.jar:]
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1172) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:79) [primefaces-3.3.1.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:322) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:116) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.authentication.ui.DefaultLoginPageGeneratingFilter.doFilter(DefaultLoginPageGeneratingFilter.java:91) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:182) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:184) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:155) [spring-security-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) [spring-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259) [spring-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.springframework.orm.hibernate4.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:119) [spring-orm-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) [spring-web-3.1.1.RELEASE.jar:3.1.1.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
    at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
    at java.lang.Thread.run(Thread.java:662) [rt.jar:1.6.0_31]

该EmployeeBean.update方法永远不会被调用，因为它上设置的断点永远不会被命中。

现在是大结局：我怎样才能防止这种情况发生LazyInitializationException。

编辑

我创建了一个解决方法，但这可能不是最好的解决方案：

在 JSF 页面中：

<p:dialog dynamic="true" onShow="loadSelectedEmployee()">
    <h:form>
        <p:remoteCommand action="#{employeeBean.loadSelectedEmployee}" name="loadSelectedEmployee" update=":editEmployeeDialogContent" />
    </h:form>
    <p:outputPanel layout="block" id="editEmployeeDialogContent">
        <h:form rendered="#{employeeBean.selectedEmployeeLoaded}">
            <p:selectCheckboxMenu label="Locations" value="#{employeeBean.selectedEmployee.locations}">
                <f:selectItems var="location" itemLabel="#{location.name}" value="#{employeeBean.locations}" />
            </p:selectCheckboxMenu>

            <p:commandButton value="save" action="#{employeeBean.update}"/>
        </h:form>
    </p:outputPanel>
</p:dialog>

在支持 bean 中：

public void loadSelectedEmployee()
{
    if (!selectedEmployeeLoaded)
    {
        selectedEmployee.setLocations(locationManager
                .getByEmployee(selectedEmployee));
        selectedEmployee.setRoles(roleManager
                .getByEmployee(selectedEmployee));
        selectedEmployeeLoaded = true;
    }
}
4

2 回答 2

1

这绝对是一个错误，我猜是在 Primefaces 或 Jboss-jsf-api-2.1 中。我可以直接在控制器中修改 PersistenSet，因此它肯定会急切地加载，但是当绑定到 JSF 组件时（我使用的是 Primefaces selectCheckboxMenu），它也会抛出 LazyInitalizationException。

于 2012-12-10T16:15:16.157 回答
0

如果您对一个与标记为“eager”没有关系的实体执行 HQL，将继续使用“lazy”的品牌并尝试在“get”时查询数据。

对于这种情况，强制初始化关系的示例是：

Hibernate.initialize(e.getLocations());

融合的：

@Transactional(readOnly = true)
public Employee getEager(Long id)
{
    Query q = sessionFactory.getCurrentSession().createQuery("select e from Employee e join fetch e.locations where e.id = :id");
    q.setParameter("id", id);
    try
    {
        final Employee e = (Employee) q.uniqueResult();
        if(e != null){
            Hibernate.initialize(e.getLocations());
        }
        return e;

    }
    catch (NonUniqueObjectException ex)
    {
        //Exception logging/handling
        return null;
    }
}

问候，

于 2012-08-28T12:12:18.117 回答