GAE / J数据存储Presistent Jdo删除问题

目前我的父母 class 看起来像这样，

public class UserVotesJDO {

@PrimaryKey
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private Key key;

    @Persistent
    private String mediaId;

    @Persistent(dependent="true")
    private LikesJDO likes;

    @Persistent(dependent="true")
    private HatesJDO hates;

//使用getter和setter以及其他变量}

而我的Child class讨厌JDO看起来像

@PersistenceCapable(detachable = "true")
public class HatesJDO {

@PrimaryKey
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private Key key;

@Persistent
private int count;

private List<UserJDO> hatesUsersList;
}

UserJDO是另一个子类，如下所示，

@PersistenceCapable(detachable="true")
public class UserJDO {

@PrimaryKey
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
    private Key key;

@Persistent
private String userId;

@Persistent
private String userName;

@Persistent
private String fullName;

@Persistent
private String userEmail;
}

我的逻辑是，当我删除UserVote时，我不再需要那些依赖孩子的讨厌和喜欢，而且其UserJDO如此 when i try to delete UserVotesJDO Object, am getting warning in console as below

Delete of com.shoewars.jdo.UserVotesJDO@8b4163 needs delete of related object at com.shoewars.jdo.ShoeWarsUserVotesJDO.hates but cannot delete it direct since FK is here

我得到这一点外键是当前引用或使用.....

任何人都可以帮我解决这个问题！

由于这是我的第一篇文章，我不知道如何正确发布，无论如何，我会解释我正在尝试做什么

我有一个JDO，它存储了一个图像ID，以及那些喜欢这个图像的人的信息以及那些讨厌这个图像的人

为此，我创建了两个JDO likesJDO和HatesJDO，分别存储列表 .

所以，当我在jdo中保存关于投票的信息时，会发生以下事情

• 获取用户信息并将其相应地存储在不喜欢或喜欢的UsersList中

• 将这些添加到UserVote JDO以及图像ID

• 终于坚持了下来

现在，我的问题是，当我删除UserVote JDO时，我希望删除hatesJDO和likesJDO中的那些记录，为什么我已添加

@Persistent(dependent="true")
private LikesJDO likes;

@Persistent(dependent="true")
private HatesJDO hates;

这些台词

但是现在，这样做会有异常

stacktrace将是：

com.uservote.service.UserVotesOperations updateUserVoteForMedia: Cannot read fields from a deleted object
javax.jdo.JDOUserException: Cannot read fields from a deleted object
FailedObject:com.google.appengine.api.datastore.Key:UserVotesJDO(80003)/LikesJDO(1)/UserJDO(2001)
    at org.datanucleus.api.jdo.state.PersistentDeleted.transitionReadField(PersistentDeleted.java:116)
    at org.datanucleus.state.AbstractStateManager.transitionReadField(AbstractStateManager.java:838)
    at org.datanucleus.state.JDOStateManager.isLoaded(JDOStateManager.java:1699)
    at com.uservotes.jdo.UserJDO.jdoGetuserId(UserJDO.java)
    at com.uservotes.jdo.UserJDO.getUserDTO(UserJDO.java:157)
    at com.uservotes.service.InstagramApiService.convertToUserDtoList(InstagramApiService.java:555)
    at com.uservotes.jdo.LikesJDO.getLikesDTO(LikesJDO.java:95)
    at com.uservotes.jdo.uservotesUserVotesJDO.getuservotesUserVotesDTO(uservotesUserVotesJDO.java:109)
    at com.uservotes.service.UserVotesOperations.updateUserVoteForMedia(UserVotesOperations.java:242)
    at com.uservotes.service.UserVotesOperations.updateUserVoteForMediaList(UserVotesOperations.java:162)
    at com.uservotes.controller.UserVotesController.hanldeUpdateUserVotesRequest(UserVotesController.java:111)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at com.google.apphosting.runtime.security.shared.intercept.java.lang.reflect.Method_$1.run(Method_.java:165)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.apphosting.runtime.security.shared.intercept.java.lang.reflect.Method_.privilegedInvoke(Method_.java:163)
    at com.google.apphosting.runtime.security.shared.intercept.java.lang.reflect.Method_.invoke_(Method_.java:124)
    at com.google.apphosting.runtime.security.shared.intercept.java.lang.reflect.Method_.invoke(Method_.java:43)
    at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:213)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
    at com.google.apphosting.utils.servlet.ParseBlobUploadFilter.doFilter(ParseBlobUploadFilter.java:102)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.apphosting.runtime.jetty.SaveSessionFilter.doFilter(SaveSessionFilter.java:35)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
    at com.google.apphosting.runtime.jetty.AppVersionHandlerMap.handle(AppVersionHandlerMap.java:266)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
    at org.mortbay.jetty.Server.handle(Server.java:326)
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
    at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)
    at com.google.apphosting.runtime.jetty.RpcRequestParser.parseAvailable(RpcRequestParser.java:76)
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
    at com.google.apphosting.runtime.jetty.JettyServletEngineAdapter.serviceRequest(JettyServletEngineAdapter.java:146)
    at com.google.apphosting.runtime.JavaRuntime$RequestRunnable.run(JavaRuntime.java:447)
    at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:454)
    at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:461)
    at com.google.tracing.TraceContext.runInContext(TraceContext.java:703)
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:338)
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:330)
    at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:458)
    at com.google.apphosting.runtime.ThreadGroupPool$PoolEntry.run(ThreadGroupPool.java:251)
    at java.lang.Thread.run(Thread.java:679)