对于急切获取（分离）的集合的LazyInitializationException

时间：2012-08-27 20:29:06

标签： ajax hibernate jpa primefaces lazy-initialization

首先是一些信息：

  • 我正在使用：
    • Spring 3.1.1.RELEASE
    • Hibernate 4.1.5.SP1
    • JSF 2.0？
    • OpenSessionInViewFilter（org.springframework.orm.hibernate4.support.OpenSessionInViewFilter）
    • PrimeFaces 3.3.1
    • Lombok 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Location的集合），我无法在没有Employee.getLocations().add()的情况下致电LazyInitializationException。使用基于非JPA的集合作为传输对象可以正常工作。

长版：

我有一个实体Employee，其中包含Location s：

的集合 
@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>();
}

Employee从Person延伸，其中包含一些字符串，如名称等，但这些字符串不相关。

@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;
}

Location类也非常简单：

@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Location添加到现有的Employee。为此，我急切地使用以下支持bean加载Employee：

@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;
    }

    //...
}

包含预先加载查询的EmployeeDAO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，它会加载employeeFull属性，并使用selectCheckboxMenu填充Location并将Location标记为Employee具有

但是，当我点击保存按钮（不更改任何内容）并且表单已提交时，Employee.locations集合会显示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]

永远不会调用EmployeeBean.update方法，因为它上面设置的断点永远不会被命中。

现在为大结局：如何防止这种情况LazyInitializationException。

修改

我已经创建了一种解决方法，但这可能不是最佳解决方案：

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;
    }
}

2 个答案:

答案 0 :(得分：1)

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

答案 1 :(得分：0)

如果您对与标记为“eager”无关的实体执行HQL，则会继续使用“lazy”品牌，并尝试在“get”时查询数据。

对于这种情况，强制初始化关系的一个例子是：

Hibernate.initialize(e.getLocations());

集成：

@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;
    }
}

Regads，

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