在JPA中,在执行em.getReference()时将@ManyToOne作为@Id抛出ClassCastException

时间:2016-06-06 13:54:18

标签: java glassfish ejb jpa-2.1

我有这个简单的代码导致以下异常,可能是什么问题??

MenuPK menuPK = new MenuPK(aVenueId, aMenuId);
Menu menu = em.getReference(Menu.class, menuPK); // where em is an EntityManager
//Menu menu = em.find(Menu.class, menuPK); // this works fine!!

// full trace
Exception Description: An internal error occurred accessing the primary key object [MenuPK@3ffa].
Internal Exception: java.lang.ClassCastException: java.lang.Long cannot be cast to Venue
Descriptor: RelationalDescriptor(Menu --> [DatabaseTable(Menus)])
    VenuesWSrvc.deleteMenu(VenuesWSrvc.java:273)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1081)
    org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1153)
    com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:4695)
    com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:630)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:582)
    org.jboss.weld.ejb.AbstractEJBRequestScopeActivationInterceptor.aroundInvoke(AbstractEJBRequestScopeActivationInterceptor.java:46)
    sun.reflect.GeneratedMethodAccessor75.invoke(Unknown Source)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:582)
    com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doCall(SystemInterceptorProxy.java:163)
    com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:140)
    sun.reflect.GeneratedMethodAccessor77.invoke(Unknown Source)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:369)
    com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:4667)
    com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:4655)
    com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:212)
    com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:88)
    com.sun.proxy.$Proxy230.deleteMenu(Unknown Source)
    WebServiceFilter.doFilter(WebServiceFilter.java:139)
    org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    WebAuthFilter.doFilter(WebAuthFilter.java:186)
    org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:316)
    org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
    com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
    org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
    org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
    org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
    org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
    org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
    org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
    org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
    org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
    java.lang.Thread.run(Thread.java:745)
-----
java.lang.ClassCastException: java.lang.Long cannot be cast to Venue
    VenuesWSrvc.deleteMenu(VenuesWSrvc.java:273)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    org.glassfish.ejb.security.application.EJBSecurityManager.runMethod(EJBSecurityManager.java:1081)
    org.glassfish.ejb.security.application.EJBSecurityManager.invoke(EJBSecurityManager.java:1153)
    com.sun.ejb.containers.BaseContainer.invokeBeanMethod(BaseContainer.java:4695)
    com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:630)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:582)
    org.jboss.weld.ejb.AbstractEJBRequestScopeActivationInterceptor.aroundInvoke(AbstractEJBRequestScopeActivationInterceptor.java:46)
    sun.reflect.GeneratedMethodAccessor75.invoke(Unknown Source)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:582)
    com.sun.ejb.containers.interceptors.SystemInterceptorProxy.doCall(SystemInterceptorProxy.java:163)
    com.sun.ejb.containers.interceptors.SystemInterceptorProxy.aroundInvoke(SystemInterceptorProxy.java:140)
    sun.reflect.GeneratedMethodAccessor77.invoke(Unknown Source)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:497)
    com.sun.ejb.containers.interceptors.AroundInvokeInterceptor.intercept(InterceptorManager.java:883)
    com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    com.sun.ejb.containers.interceptors.InterceptorManager.intercept(InterceptorManager.java:369)
    com.sun.ejb.containers.BaseContainer.__intercept(BaseContainer.java:4667)
    com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:4655)
    com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:212)
    com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:88)
    com.sun.proxy.$Proxy230.deleteMenu(Unknown Source)
    WebServiceFilter.doFilter(WebServiceFilter.java:139)
    org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    WebAuthFilter.doFilter(WebAuthFilter.java:186)
    org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:316)
    org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
    com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
    org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
    org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
    org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
    org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
    org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
    org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
    org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
    org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
    org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
    org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
    java.lang.Thread.run(Thread.java:745)
-----
, 1, Failed to retrieve Menus, 1465220776471, /ws/deleteMenu, 3]
2016-06-06T16:46:16.477+0300|Fine: SELECT LAST_INSERT_ID()
2016-06-06T16:46:16.503+0300|Severe: javax.servlet.ServletException: Error invoking WebService: 'deleteMenu'
    at WebServiceFilter.doFilter(WebServiceFilter.java:276)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at WebAuthFilter.doFilter(WebAuthFilter.java:186)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:316)
    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:357)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
    at java.lang.Thread.run(Thread.java:745)
Caused by: ServiceException: Exception [EclipseLink-202] (Eclipse Persistence Services - 2.6.3.v20160428-59c81c5): org.eclipse.persistence.exceptions.DescriptorException
Exception Description: An internal error occurred accessing the primary key object [MenuPK@3ffa].
Internal Exception: java.lang.ClassCastException: java.lang.Long cannot be cast to Venue
Descriptor: RelationalDescriptor(Menu --> [DatabaseTable(Menus)])
    at VenuesWSrvc.deleteMenu(VenuesWSrvc.java:273)
    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:497)
    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:4695)
    at com.sun.ejb.EjbInvocation.invokeBeanMethod(EjbInvocation.java:630)
    at com.sun.ejb.containers.interceptors.AroundInvokeChainImpl.invokeNext(InterceptorManager.java:822)
    at com.sun.ejb.EjbInvocation.proceed(EjbInvocation.java:582)
    at org.jboss.weld.ejb.AbstractEJBRequestScopeActivationInterceptor.aroundInvoke(AbstractEJBRequestScopeActivationInterceptor.java:46)
    at sun.reflect.GeneratedMethodAccessor75.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    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:582)
    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.GeneratedMethodAccessor77.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    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:4667)
    at com.sun.ejb.containers.BaseContainer.intercept(BaseContainer.java:4655)
    at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:212)
    at com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:88)
    at com.sun.proxy.$Proxy230.deleteMenu(Unknown Source)
    at WebServiceFilter.doFilter(WebServiceFilter.java:139)
    ... 31 more
Caused by: Exception [EclipseLink-202] (Eclipse Persistence Services - 2.6.3.v20160428-59c81c5): org.eclipse.persistence.exceptions.DescriptorException
Exception Description: An internal error occurred accessing the primary key object [MenuPK@3ffa].
Internal Exception: java.lang.ClassCastException: java.lang.Long cannot be cast to Venue
Descriptor: RelationalDescriptor(Menu --> [DatabaseTable(Menus)])
    at org.eclipse.persistence.exceptions.DescriptorException.errorUsingPrimaryKey(DescriptorException.java:1937)
    at org.eclipse.persistence.internal.jpa.CMP3Policy.createBeanUsingKey(CMP3Policy.java:342)
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.getReference(UnitOfWorkImpl.java:5909)
    at org.eclipse.persistence.internal.jpa.EntityManagerImpl.getReference(EntityManagerImpl.java:1405)
    at com.sun.enterprise.container.common.impl.EntityManagerWrapper.getReference(EntityManagerWrapper.java:418)
    at VenuesWSrvc.deleteMenu(VenuesWSrvc.java:263)
    ... 62 more
Caused by: java.lang.ClassCastException: java.lang.Long cannot be cast to Venue
    at Menu._persistence_set(Menu.java)
    at org.eclipse.persistence.internal.descriptors.PersistenceObjectAttributeAccessor.setAttributeValueInObject(PersistenceObjectAttributeAccessor.java:102)
    at org.eclipse.persistence.mappings.DatabaseMapping.setAttributeValueInObject(DatabaseMapping.java:1652)
    at org.eclipse.persistence.internal.indirection.IndirectionPolicy.setRealAttributeValueInObject(IndirectionPolicy.java:340)
    at org.eclipse.persistence.mappings.ForeignReferenceMapping.setRealAttributeValueInObject(ForeignReferenceMapping.java:1683)
    at org.eclipse.persistence.internal.jpa.CMP3Policy.creat
2016-06-06T16:46:16.503+0300|Severe: eBeanUsingKey(CMP3Policy.java:338)
    ... 66 more


这是我的Venue实体

@Entity
@Table(name="Venues")
public class Venue implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "id")
    private long venueId;

    @OneToMany(mappedBy="venue")
    private List<Menu> menus;
}


还有一个代表Menus的场地可能有

@Entity
@Table(name="Menus")
@IdClass(MenuPK.class)
public class Menu implements Serializable {
    private static final long serialVersionUID = 1L;

    @Id
    @ManyToOne
    @JoinColumn(name="venueId")
    private Venue venue;

    @Id
    @Min(value=1)
    private short menuId;
}


这是Menus的PK类

public class MenuPK implements Serializable {
    private static final long serialVersionUID = 1L;

    private long venue;
    private short menuId;

    public MenuPK() {
    }
    public MenuPK(long venueId, short menuId) {
        this.venue = venueId;
        this.menuId = menuId;
    }

    public long getVenue() {
        return this.venue;
    }   
    public short getMenuId() {
        return this.menuId;
    }

    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }
        if (!(other instanceof MenuPK)) {
            return false;
        }
        MenuPK castOther = (MenuPK)other;
        return 
            (this.venue == castOther.venue) &&
            (this.menuId == castOther.menuId);
    }

    public int hashCode() {
        final int prime = 31;
        int hash = 17;
        hash = hash * prime + (int)(this.venue ^ (this.venue >>> 32));  // taken from the hashCode() implementation of java.lang.Long
        hash = hash * prime + ((int) this.menuId);

        return hash;
    }
}

1 个答案:

答案 0 :(得分:-1)

实体菜单的主键类型为:

  • 场地
  • 短menuId

表示主键的类的类型是:

  • 地点地点
  • 短menuId

这就是为什么当你试图获得一个拥有PK的实体时你得到ClassCastException