我在尝试使用 Vaadin 和 Spring-boot 使我的程序运行时遇到了问题。 尝试调用 EntityManager.persist() 或 EntityManager.merge() 时出现 IllegalArgumentException
因此，我按照此处某人提供的说明设法解决了之前的问题，该问题是在尝试使用我的存储库时出现 NullPointerException 。我不再有这个了，但我有了一个新的，IllegalArgumentException。
我在这里搜索了解决方案，但大多数问题都是关于用户定义实体(例如 com.chinalbs.entity.Conductor)的 IllegalArgumentExceptions，但我的问题如下: java.lang.IllegalArgumentException:未知实体: com.sun.proxy.$Proxy87 我读到这可能是因为我的一个实体类中缺少 @Entity 注释，但我有这些，所以情况并非如此。 尝试为我的实体包设置@EntityScan，但这也没有帮助。
我的房间实体:
@Entity
@Table(name="Room")
public class Room {
@Id
@GeneratedValue
private int id;
private String name;
private int level;
public Room() {
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getLevel() {
return level;
}
public void setLevel(int level) {
this.level = level;
}
}
我得到异常的部分:
@Transactional
@Component
public class Repository_Room_Impl implements Repository_Room{
@PersistenceContext
private EntityManager em;
@Override
public List<Room> findAll() {
return em.createQuery("select n from " + Room.class.getSimpleName() + " n").getResultList();
}
@Override
public void save(Room room) {
em.persist(room);
}
public void delete(Room room) {
em.remove(em.find(Room.class, room.getId()));
}
public void update(Room room) {
em.merge(em);
}
public List<Course> getCourses(Room room)
{
List<Course> courses = em.createQuery("select n from " + Course.class.getSimpleName() + " n WHERE n.Room = :roomID", Course.class)
.setParameter("roomID", room.getId())
.getResultList();
return courses;
}
}
堆栈跟踪:
java.lang.IllegalArgumentException: Unknown entity: com.sun.proxy.$Proxy87
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:909)
at org.hibernate.internal.SessionImpl.merge(SessionImpl.java:887)
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.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:308)
at com.sun.proxy.$Proxy87.merge(Unknown Source)
at com.example.beadando.repository.Impl.Repository_Room_Impl.update(Repository_Room_Impl.java:36)
at com.example.beadando.repository.Impl.Repository_Room_Impl$$FastClassBySpringCGLIB$$65e42158.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:749)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:295)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688)
at com.example.beadando.repository.Impl.Repository_Room_Impl$$EnhancerBySpringCGLIB$$c0f4ae10.update(<generated>)
at com.example.beadando.component.Form_Room.updateRoom(Form_Room.java:94)
at com.example.beadando.view.View_CRUD_Room.lambda$init$9b1b5227$1(View_CRUD_Room.java:54)
at com.vaadin.flow.component.ComponentEventBus.fireEventForListener(ComponentEventBus.java:205)
at com.vaadin.flow.component.ComponentEventBus.handleDomEvent(ComponentEventBus.java:373)
at com.vaadin.flow.component.ComponentEventBus.lambda$addDomTrigger$dd1b7957$1(ComponentEventBus.java:264)
at com.vaadin.flow.internal.nodefeature.ElementListenerMap.lambda$fireEvent$2(ElementListenerMap.java:420)
at java.util.ArrayList.forEach(ArrayList.java:1249)
at com.vaadin.flow.internal.nodefeature.ElementListenerMap.fireEvent(ElementListenerMap.java:420)
at com.vaadin.flow.server.communication.rpc.EventRpcHandler.handleNode(EventRpcHandler.java:59)
at com.vaadin.flow.server.communication.rpc.AbstractRpcInvocationHandler.handle(AbstractRpcInvocationHandler.java:64)
at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocationData(ServerRpcHandler.java:387)
at com.vaadin.flow.server.communication.ServerRpcHandler.lambda$handleInvocations$1(ServerRpcHandler.java:368)
at java.util.ArrayList.forEach(ArrayList.java:1249)
at com.vaadin.flow.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:368)
at com.vaadin.flow.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:310)
at com.vaadin.flow.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:89)
at com.vaadin.flow.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:40)
at com.vaadin.flow.server.VaadinService.handleRequest(VaadinService.java:1507)
at com.vaadin.flow.server.VaadinServlet.service(VaadinServlet.java:242)
at com.vaadin.flow.spring.SpringServlet.service(SpringServlet.java:81)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:712)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:459)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:352)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:312)
at org.springframework.web.servlet.mvc.ServletForwardingController.handleRequestInternal(ServletForwardingController.java:141)
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:177)
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:52)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:200)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:836)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1747)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.hibernate.MappingException: Unknown entity: com.sun.proxy.$Proxy87
at org.hibernate.metamodel.internal.MetamodelImpl.entityPersister(MetamodelImpl.java:670)
at org.hibernate.internal.SessionImpl.getEntityPersister(SessionImpl.java:1692)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:147)
at org.hibernate.event.internal.DefaultMergeEventListener.onMerge(DefaultMergeEventListener.java:69)
at org.hibernate.internal.SessionImpl.fireMerge(SessionImpl.java:901)
... 91 more
我可能会错过什么？
最佳答案
在这种情况下，错误和堆栈跟踪非常有用:未知实体:com.sun.proxy.$Proxy87 意味着您正在将一个对象传递给 EntityManager不是它所了解的实体——或者根本不是实体。
堆栈跟踪还为您提供了 Repository_Room_Impl 中违规行的方法名称和行号:
em.merge(em);
关于java - 未知实体 : com. sun.proxy.$Proxy87，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56518793/