Nun, ich habe Google durchsucht und viele Ergebnisse gefunden, aber keines von ihnen konnte mein Problem beantworten. Also, hier geht es.
Ich versuche, Spring MVC und Spring Data JPA zu studieren, indem ich eine minimale Implementierung des pinterest-Klons durchführe. Im Folgenden sind die Teile des Codes aufgeführt, die meiner Meinung nach für mein Problem relevant sind.
Modelle / Entitäten
@Entity
@Table(name = "pin_item")
public class PinItem implements Serializable {
// properties ...
@JoinColumn(name = "board_id", referencedColumnName = "user_board_id")
@ManyToOne(optional = false)
private UserBoard board;
// getters and setters...
}
@Entity
@Table(name = "user_board")
public class UserBoard implements Serializable {
// properties ...
@OneToMany(cascade = CascadeType.ALL, mappedBy = "board")
private List<PinItem> pinItemList;
// getters and setters...
}
Bedienung
@Service
@Transactional(readOnly = true)
public class BoardServiceImpl implements BoardService {
@Autowired
private UserBoardRepository boardRepository;
@Override
public List<UserBoard> findLatestBoards() {
PageRequest request = new PageRequest(
0, PresentationUtil.PAGE_SIZE,
Sort.Direction.DESC, "boardId"
);
return boardRepository.findAll(request).getContent();
}
// Other Methods
}
Repository
public interface UserBoardRepository extends JpaRepository<UserBoard, Integer> {
}
Wenn ich jetzt die findLatestBoards
Methode BoardService
aufrufe, wird die Ausnahme "Keine Eigenschaft gefunden" in der Zeile ausgelöst return boardRepository.findAll(request).getContent();
. Hier ist der Auszug aus dem Tomcat-Protokoll.
AUSTESTUNGSPROTOKOLL
12:28:44,254 DEBUG AnnotationTransactionAttributeSource:106 - Adding transactional method 'findLatestBoards' with attribute: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; ''
12:28:44,254 DEBUG DefaultListableBeanFactory:246 - Returning cached instance of singleton bean 'transactionManager'
12:28:44,254 DEBUG JpaTransactionManager:366 - Creating new transaction with name [com.tecnooc.picpin.service.impl.BoardServiceImpl.findLatestBoards]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; ''
12:28:44,254 DEBUG JpaTransactionManager:369 - Opened new EntityManager [org.hibernate.ejb.EntityManagerImpl@75284194] for JPA transaction
12:28:44,255 DEBUG AbstractTransactionImpl:158 - begin
12:28:44,255 DEBUG LogicalConnectionImpl:212 - Obtaining JDBC connection
12:28:44,255 DEBUG DriverManagerDataSource:162 - Creating new JDBC DriverManager Connection to [jdbc:mysql://localhost:3306/pic_pin]
12:28:44,266 DEBUG LogicalConnectionImpl:218 - Obtained JDBC connection
12:28:44,267 DEBUG JdbcTransaction:69 - initial autocommit status: true
12:28:44,267 DEBUG JdbcTransaction:71 - disabling autocommit
12:28:44,267 DEBUG JpaTransactionManager:401 - Exposing JPA transaction as JDBC transaction [org.springframework.orm.jpa.vendor.HibernateJpaDialect$HibernateConnectionHandle@370da60e]
12:28:44,274 DEBUG TransactionalRepositoryProxyPostProcessor$CustomAnnotationTransactionAttributeSource:286 - Adding transactional method 'findAll' with attribute: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; ''
12:28:44,274 DEBUG DefaultListableBeanFactory:246 - Returning cached instance of singleton bean 'transactionManager'
12:28:44,274 DEBUG JpaTransactionManager:332 - Found thread-bound EntityManager [org.hibernate.ejb.EntityManagerImpl@75284194] for JPA transaction
12:28:44,274 DEBUG JpaTransactionManager:471 - Participating in existing transaction
12:28:44,279 DEBUG CachedIntrospectionResults:159 - Not strongly caching class [java.io.Serializable] because it is not cache-safe
12:28:44,281 DEBUG JpaTransactionManager:851 - Participating transaction failed - marking existing transaction as rollback-only
12:28:44,281 DEBUG JpaTransactionManager:559 - Setting JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@75284194] rollback-only
12:28:44,283 DEBUG JpaTransactionManager:844 - Initiating transaction rollback
12:28:44,284 DEBUG JpaTransactionManager:534 - Rolling back JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@75284194]
12:28:44,284 DEBUG AbstractTransactionImpl:203 - rolling back
12:28:44,284 DEBUG JdbcTransaction:164 - rolled JDBC Connection
12:28:44,285 DEBUG JdbcTransaction:126 - re-enabling autocommit
12:28:44,285 DEBUG JpaTransactionManager:594 - Closing JPA EntityManager [org.hibernate.ejb.EntityManagerImpl@75284194] after transaction
12:28:44,285 DEBUG EntityManagerFactoryUtils:338 - Closing JPA EntityManager
12:28:44,286 DEBUG LogicalConnectionImpl:232 - Releasing JDBC connection
12:28:44,286 DEBUG LogicalConnectionImpl:250 - Released JDBC connection
12:28:44,287 DEBUG ExceptionHandlerExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.tecnooc.picpin.controller.BoardController.latest(javax.servlet.http.HttpSession,org.springframework.ui.Model)]: org.springframework.data.mapping.PropertyReferenceException: No property board found for type com.tecnooc.picpin.model.UserBoard
12:28:44,289 DEBUG ResponseStatusExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.tecnooc.picpin.controller.BoardController.latest(javax.servlet.http.HttpSession,org.springframework.ui.Model)]: org.springframework.data.mapping.PropertyReferenceException: No property board found for type com.tecnooc.picpin.model.UserBoard
12:28:44,290 DEBUG DefaultHandlerExceptionResolver:132 - Resolving exception from handler [public java.lang.String com.tecnooc.picpin.controller.BoardController.latest(javax.servlet.http.HttpSession,org.springframework.ui.Model)]: org.springframework.data.mapping.PropertyReferenceException: No property board found for type com.tecnooc.picpin.model.UserBoard
12:28:44,291 DEBUG DispatcherServlet:959 - Could not complete request
Ausnahme
Die Ausnahme ist " org.springframework.data.mapping.PropertyReferenceException: No property board found for type com.tecnooc.picpin.model.UserBoard
". Aber wenn ich es richtig verstanden habe, ist die Eigenschaft board
in vorhanden PinItem
und wird korrekt mit mappedBy = "board"
in zugeordnet UserBoard
.
org.springframework.data.mapping.PropertyReferenceException: No property board found for type com.tecnooc.picpin.model.UserBoard
at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:75)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:327)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:353)
at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:307)
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:271)
at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:245)
at org.springframework.data.jpa.repository.query.QueryUtils.toJpaOrder(QueryUtils.java:408)
at org.springframework.data.jpa.repository.query.QueryUtils.toOrders(QueryUtils.java:372)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.getQuery(SimpleJpaRepository.java:456)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.getQuery(SimpleJpaRepository.java:437)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:319)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:289)
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 org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:333)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:318)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:155)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.data.jpa.repository.support.LockModeRepositoryPostProcessor$LockModePopulatingMethodIntercceptor.invoke(LockModeRepositoryPostProcessor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:91)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy147.findAll(Unknown Source)
at com.tecnooc.picpin.service.impl.BoardServiceImpl.findLatestBoards(BoardServiceImpl.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 org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy148.findLatestBoards(Unknown Source)
at com.tecnooc.picpin.controller.BoardController.latest(BoardController.java:31)
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 org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:827)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
Ich verstehe nicht, warum diese Ausnahme ausgelöst wird. Irgendeine Idee, warum es passiert?
Hinweis: Ich verwende den Ruhezustand als Persistenzanbieter. Der Code-Teil, den ich hier eingefügt habe, ist meiner Meinung nach für das Problem relevant. Wenn dies nicht der Fall ist, lassen Sie es mich wissen und ich werde die Frage mit dem erforderlichen Teil aktualisieren.