我有一个具有列数据类型（hstore）的表，hstore中的值具有3种可能性，要么具有value，要么具有[null]要么没有值（空）。使用Spring Data JPA以及（{https://github.com/The-Alchemist/hibernate-postgresql）。在空的hstore和具有值的hstore的情况下，我能够成功获得等效于hstore的Map，但是当hstore为null时，它将引发Null Pointer Exception。
//Query to insert into hstore where test is of type hstore
INSERT INTO datafeeds.test(test) VALUES(null);
//Entity class
@Data
@Entity
@Table (schema = "datafeeds", name = "\"PartnerHotel\"")
@TypeDefs({
@TypeDef(name = "hstore", typeClass = HstoreType.class)
})
public class PartnerHotel implements Serializable{
@Column(name = "descriptions")
@Type(type = "hstore")
private Map<String,String> descriptions = new ConcurrentHashMap<>();
// Some other attributes
}
//Exception stack trace:
Caused by: java.util.concurrent.CompletionException: java.lang.RuntimeException: java.lang.NullPointerException
at java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:273) ~[na:1.8.0_202]
at java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:280) ~[na:1.8.0_202]
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1592) ~[na:1.8.0_202]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_202]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_202]
... 1 common frames omitted
Caused by: java.lang.RuntimeException: java.lang.NullPointerException
at de.idealo.reise.partnerhotelchangedprocessor.service.AccomodationClusterService.createCluster(AccomodationClusterService.java:32) ~[classes/:na]
at de.idealo.reise.partnerhotelchangedprocessor.service.ClusterBuilderService.handleCreateEvent(ClusterBuilderService.java:64) ~[classes/:na]
at de.idealo.reise.partnerhotelchangedprocessor.service.ClusterBuilderService.hotelChangeHandler(ClusterBuilderService.java:47) ~[classes/:na]
at de.idealo.reise.partnerhotelchangedprocessor.service.ClusterBuilderService.run(ClusterBuilderService.java:35) ~[classes/:na]
at de.idealo.reise.partnerhotelchangedprocessor.service.ChangeListenerService.lambda$recieve$0(ChangeListenerService.java:43) ~[classes/:na]
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590) ~[na:1.8.0_202]
... 3 common frames omitted
Caused by: java.lang.NullPointerException: null
at org.postgresql.util.HStoreConverter.fromString(HStoreConverter.java:116) ~[postgresql-42.2.5.jar:42.2.5]
at com.github.thealchemist.pg_hibernate.HstoreType.nullSafeGet(HstoreType.java:63) ~[hibernate-postgresql-1.0.19.jar:na]
at org.hibernate.type.CustomType.nullSafeGet(CustomType.java:119) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.type.AbstractType.hydrate(AbstractType.java:91) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:3007) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1746) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1672) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.getRow(Loader.java:1561) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:731) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.processResultSet(Loader.java:990) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.doQuery(Loader.java:948) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:340) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2689) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2672) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2506) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.Loader.list(Loader.java:2501) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:504) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:395) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:220) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1508) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1537) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1505) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.query.Query.getResultList(Query.java:135) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.query.criteria.internal.compile.CriteriaQueryTypeQueryAdapter.getResultList(CriteriaQueryTypeQueryAdapter.java:74) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at sun.reflect.GeneratedMethodAccessor166.invoke(Unknown Source) ~[na:na]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_202]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_202]
at org.springframework.orm.jpa.SharedEntityManagerCreator$DeferredQueryInvocationHandler.invoke(SharedEntityManagerCreator.java:402) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at com.sun.proxy.$Proxy126.getResultList(Unknown Source) ~[na:na]
at org.springframework.data.jpa.repository.query.JpaQueryExecution$CollectionExecution.doExecute(JpaQueryExecution.java:129) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:91) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:136) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:125) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:605) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$invoke$3(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:294) ~[spring-tx-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:135) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at com.sun.proxy.$Proxy112.findByHotelIdAndIsOnlineAndIsRemovedByUser(Unknown Source) ~[na:na]
at de.idealo.reise.partnerhotelchangedprocessor.service.AccomodationClusterService.createCluster(AccomodationClusterService.java:26) ~[classes/:na]
我希望在[null] hstore值或hstore中没有值的情况下，我应该得到一个空的HashMap。