我有以下实体：
@Entity public class Employee implements Serializable{ private static final long serialVersionUID = 3454567L; @Id @GeneratedValue(strategy=GenerationType.AUTO) private int empId; @Column private String username; public int getEmpId() { return empId; } public void setEmpId(int empId) { this.empId = empId; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } }
还有以下EJB：
public class UserDAO implements UserDAOInterface{ @PersistenceContext(unitName = "MainPersistenceUnit") private EntityManager em; @Override public void persist(Employee sdf) { try { em.persist(sdf); } catch (Exception e) { Logger.getLogger(getClass().getName()).log(Level.SEVERE, "exception caught", e); throw new RuntimeException(e); } } }
调用persist时，将引发具有以下根本原因的异常：
Caused by: org.hibernate.PropertyAccessException: could not get a field value by reflection getter of com.mine.projs.library.entity.Employee.empId at org.hibernate.property.DirectPropertyAccessor$DirectGetter.get(DirectPropertyAccessor.java:60) at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:346) at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4746) at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4465) at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:243) at org.hibernate.event.internal.AbstractSaveEventListener.getEntityState(AbstractSaveEventListener.java:511) at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:116) at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75) at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:811) at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:784) at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:789) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181) ... 100 more
这是GlassFish 4.1的完整日志：
Info: HHH000204: Processing PersistenceUnitInfo [ name: MainPersistenceUnit ...] Info: HHH000412: Hibernate Core {4.3.7.Final} Info: HHH000206: hibernate.properties not found Info: HHH000021: Bytecode provider name : javassist Info: HCANN000001: Hibernate Commons Annotations {4.0.5.Final} Info: HHH000400: Using dialect: org.hibernate.dialect.MySQL5InnoDBDialect Info: HHH000397: Using ASTQueryTranslatorFactory Info: HHH000227: Running hbm2ddl schema export Info: Hibernate: drop table if exists Employee Info: Hibernate: create table Employee (empId integer not null auto_increment, username varchar(255), primary key (empId)) ENGINE=InnoDB Info: HHH000230: Schema export complete Info: Portable JNDI names for EJB UserService: [java:global/Library/UserService, java:global/Library/UserService!com.mine.projs.library.service.interfaces.UserServiceInterface] WARN: WELD-000411: Observer method [BackedAnnotatedMethod] private org.glassfish.jersey.gf.cdi.internal.CdiComponentProvider.processAnnotatedType(@Observes ProcessAnnotatedType<Object>) receives events for all annotated types. Consider restricting events using @WithAnnotations or a generic type with bounds. WARN: WELD-000411: Observer method [BackedAnnotatedMethod] public org.glassfish.jms.injection.JMSCDIExtension.processAnnotatedType(@Observes ProcessAnnotatedType<Object>) receives events for all annotated types. Consider restricting events using @WithAnnotations or a generic type with bounds. WARN: WELD-000411: Observer method [BackedAnnotatedMethod] org.glassfish.sse.impl.ServerSentEventCdiExtension.processAnnotatedType(@Observes ProcessAnnotatedType<Object>, BeanManager) receives events for all annotated types. Consider restricting events using @WithAnnotations or a generic type with bounds. Info: Initializing Mojarra 2.2.7 ( 20140610-1547 https://svn.java.net/svn/mojarra~svn/tags/2.2.7@13362) for context '/libr' Info: Running on PrimeFaces 5.1 Info: Loading application [Library] at [/libr] Info: Library was successfully deployed in 3,429 milliseconds. Info: inside getAna Info: inside Create User Severe: exception caught javax.persistence.PersistenceException: org.hibernate.PropertyAccessException: could not get a field value by reflection getter of com.mine.projs.library.entity.Employee.empId at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1763) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1677) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1683) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1187) at com.sun.enterprise.container.common.impl.EntityManagerWrapper.persist(EntityManagerWrapper.java:287) at com.mine.projs.library.dao.UserDAO.persist(UserDAO.java:20) at com.mine.projs.library.service.UserService.createUSer(UserService.java:21) 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:483) at org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1081) at org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1153) at com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:4786) at com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:656) at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822) at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:608) at org.jboss.weld.ejb.AbstractEJBRequestScopeActivationInterceptor.aroundInvoke(AbstractEJBRequestScopeActivationInterceptor.java:46) at org.jboss.weld.ejb.SessionBeanInterceptor.aroundInvoke(SessionBeanInterceptor.java:52) at sun.reflect.GeneratedMethodAccessor103.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883) at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822) at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:608) at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doCall(SystemInterceptorProxy.java:163) at com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:140) at sun.reflect.GeneratedMethodAccessor151.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883) at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822) at com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:369) at com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:4758) at com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:4746) at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:212) at com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:88) at com.sun.proxy.$Proxy321.createUSer(Unknown Source) 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:483) at org.jboss.weld.util.reflection.Reflections.invokeAndUnwrap(Reflections.java:414) at org.jboss.weld.bean.proxy.EnterpriseBeanProxyMethodHandler.invoke(EnterpriseBeanProxyMethodHandler.java:127) at org.jboss.weld.bean.proxy.EnterpriseTargetBeanInstance.invoke(EnterpriseTargetBeanInstance.java:56) at org.jboss.weld.bean.proxy.InjectionPointPropagatingEnterpriseTargetBeanInstance.invoke(InjectionPointPropagatingEnterpriseTargetBeanInstance.java:65) at org.jboss.weld.bean.proxy.ProxyMethodHandler.invoke(ProxyMethodHandler.java:100) at com.mine.projs.library.service.UserServiceInterface$243194531$Proxy$_$$_Weld$EnterpriseProxy$.createUSer(Unknown Source) at com.mine.projs.library.view.UserBean.getAna(UserBean.java:29) 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:483) at javax.el.BeanELResolver.getValue(BeanELResolver.java:363) at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176) at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203) at com.sun.el.parser.AstValue.getValue(AstValue.java:140) at com.sun.el.parser.AstValue.getValue(AstValue.java:204) at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:226) at org.jboss.weld.el.WeldValueExpression.getValue(WeldValueExpression.java:50) at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109) at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194) at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182) at javax.faces.component.UICommand.getValue(UICommand.java:218) at com.sun.faces.renderkit.html_basic.ButtonRenderer.encodeBegin(ButtonRenderer.java:119) at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:864) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1854) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859) at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859) at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:456) at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:133) at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:337) at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120) at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:415) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:282) at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167) at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:201) at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:175) at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235) at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201) at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133) at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112) at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:561) at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:565) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:545) at java.lang.Thread.run(Thread.java:745) Caused by: org.hibernate.PropertyAccessException: could not get a field value by reflection getter of com.mine.projs.library.entity.Employee.empId at org.hibernate.property.DirectPropertyAccessor$DirectGetter.get(DirectPropertyAccessor.java:60) at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:346) at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4746) at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4465) at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:243) at org.hibernate.event.internal.AbstractSaveEventListener.getEntityState(AbstractSaveEventListener.java:511) at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:116) at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75) at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:811) at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:784) at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:789) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181) ... 100 more
这是怎么引起的，我该如何解决？
我有同样的问题。这个错误似乎是从HB 4.3.6开始的，并且一直存在，我正在尝试4.3.10。具有相同的结果。
在我看来，访问实体字段的方式在HB 4.3.6+中已更改，可能与类加载器有关。在HB 4.3.6之前，将DB Driver jar文件嵌入ear文件可以正常工作（非常容易清理）。在4.3.6之后，它不起作用（没有找到类的异常），现在必须将驱动程序jar文件放入Glassfish的lib文件夹中。
胡安
