在GAE / J和JPA上使用@MappedSuperclass时，“字段jdoFieldFlags是冲突的”
在查询GAE / J上的mappedsuperclass扩展的实体时出错。
MappedSuperClass
import java.sql.Timestamp; import javax.persistence.MappedSuperclass; @MappedSuperclass public abstract class AbstractModel { private String lastModifiedBy; private Timestamp createTimestamp; private Timestamp modifyTimestamp; private Integer version; // setters & getters } 实体
import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.Table; @Entity @Table(name = "EMPLOYEE") public class EmployeeModel extends AbstractModel { @Id private Integer id; private String address; private String name; private String position; // setters & getters }
JPA查询如下所示。
Query q = em.createNativeQuery("SELECT * FROM EMPLOYEE", EmployeeModel.class); @SuppressWarnings("unchecked") List list = q.getResultList();
我收到了错误
javax.persistence.PersistenceException: Result Class query field names are not case sensitive. It does not allow fields with same name, but in a different case. For instance, the field "jdoFieldFlags" is conflicting. at org.datanucleus.api.jpa.NucleusJPAHelper.getJPAExceptionForNucleusException(NucleusJPAHelper.java:302) at org.datanucleus.api.jpa.JPAQuery.getResultList(JPAQuery.java:202) at test20140919.EmployeeDao.list(EmployeeDao.java:21) at test20140919.EmployeeLogic.list(EmployeeLogic.java:34) at test20140919.EmployeeAction.list(EmployeeAction.java:45) 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:606) at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:115) at com.google.api.server.spi.SystemService.invokeServiceMethod(SystemService.java:359) at com.google.api.server.spi.SystemServiceServlet.execute(SystemServiceServlet.java:160) at com.google.api.server.spi.SystemServiceServlet.doPost(SystemServiceServlet.java:118) 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$CachedChain.doFilter(ServletHandler.java:1166) at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:127) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63) 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 com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349) at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116) at org.mortbay.jetty.servlet.ServletHandler$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.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:98) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:491) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at org.mortbay.jetty.Server.handle(Server.java:326) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) Caused by: org.datanucleus.exceptions.NucleusUserException: Result Class query field names are not case sensitive. It does not allow fields with same name, but in a different case. For instance, the field "jdoFieldFlags" is conflicting. at org.datanucleus.store.rdbms.query.ResultClassROF.populateDeclaredFieldsForUserType(ResultClassROF.java:508) at org.datanucleus.store.rdbms.query.ResultClassROF.populateDeclaredFieldsForUserType(ResultClassROF.java:514) at org.datanucleus.store.rdbms.query.ResultClassROF.access$100(ResultClassROF.java:65) at org.datanucleus.store.rdbms.query.ResultClassROF$1.run(ResultClassROF.java:228) at java.security.AccessController.doPrivileged(Native Method) at org.datanucleus.store.rdbms.query.ResultClassROF.(ResultClassROF.java:224) at org.datanucleus.store.rdbms.query.RDBMSQueryUtils.getResultObjectFactoryForNoCandidateClass(RDBMSQueryUtils.java:532) at org.datanucleus.store.rdbms.query.SQLQuery.performExecute(SQLQuery.java:295) at org.datanucleus.store.query.Query.executeQuery(Query.java:1789) at org.datanucleus.store.query.AbstractSQLQuery.executeWithMap(AbstractSQLQuery.java:345) at org.datanucleus.api.jpa.JPAQuery.getResultList(JPAQuery.java:185) ... 48 more
消息说“字段jdoFieldFlags是冲突的。”，但任何字段都不重复，我没有定义jdoFieldFlags字段。
为什么会发生此错误？ 请告诉我如何解决这个错误。
在EmployeeModel中定义所有字段而不扩展AbstractModel可以删除此错误。 但我想避免使用此解决方案，因为AbstractModel中的字段对于我的应用程序中的所有表都是通用的。
[更新] App Engine版本为1.9.11，存储为cloudSQL。 表定义如下。
CREATE TABLE `EMPLOYEE` ( `address` varchar(50) NOT NULL, `name` varchar(50) NOT NULL, `position` varchar(45) DEFAULT NULL, `id` int(11) NOT NULL, `lastModifiedBy` varchar(45) NOT NULL, `createTimestamp` datetime NOT NULL, `modifyTimestamp` datetime NOT NULL, `version` int(11) NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
[Update2]我已将DataNucleus更新到版本4.0.2，但发生了类似的错误。 我没有重复的字段和dnFieldFlags。
javax.persistence.PersistenceException: Result Class query field names are not case sensitive. It does not allow fields with same name, but in a different case. For instance, the field "dnFieldFlags" is conflicting. at org.datanucleus.api.jpa.NucleusJPAHelper.getJPAExceptionForNucleusException(NucleusJPAHelper.java:308) at org.datanucleus.api.jpa.JPAQuery.getResultList(JPAQuery.java:213) at (my app : List list = q.getResultList();) 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:606) at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:115) at com.google.api.server.spi.SystemService.invokeServiceMethod(SystemService.java:359) at com.google.api.server.spi.SystemServiceServlet.execute(SystemServiceServlet.java:160) at com.google.api.server.spi.SystemServiceServlet.doPost(SystemServiceServlet.java:118) 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.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:127) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349) at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:98) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:491) 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$RequestHandler.content(HttpConnection.java:938) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) Caused by: org.datanucleus.exceptions.NucleusUserException: Result Class query field names are not case sensitive. It does not allow fields with same name, but in a different case. For instance, the field "dnFieldFlags" is conflicting. at org.datanucleus.store.rdbms.query.ResultClassROF.populateDeclaredFieldsForUserType(ResultClassROF.java:507) at org.datanucleus.store.rdbms.query.ResultClassROF.populateDeclaredFieldsForUserType(ResultClassROF.java:512) at org.datanucleus.store.rdbms.query.ResultClassROF.access$100(ResultClassROF.java:65) at org.datanucleus.store.rdbms.query.ResultClassROF$1.run(ResultClassROF.java:225) at java.security.AccessController.doPrivileged(Native Method) at org.datanucleus.store.rdbms.query.ResultClassROF.(ResultClassROF.java:221) at org.datanucleus.store.rdbms.query.RDBMSQueryUtils.getResultObjectFactoryForNoCandidateClass(RDBMSQueryUtils.java:547) at org.datanucleus.store.rdbms.query.SQLQuery.performExecute(SQLQuery.java:289) at org.datanucleus.store.query.Query.executeQuery(Query.java:1840) at org.datanucleus.store.query.AbstractSQLQuery.executeWithMap(AbstractSQLQuery.java:356) at org.datanucleus.api.jpa.JPAQuery.getResultList(JPAQuery.java:197) ... 48 more
我试过EclipseLink。 以上代码工作正常。