使用 JPA 查询数据库时的未知来源

Question

I have a strange error when running tests in SpringBoot using JPA to interact with a postgresql database. A test class successfully inserts an entity to the database and I can see it exists, but when attempting to delete (or just read it), the crud repository object throws a NullPointerException where the problem seems to be further in the StackTrace where it is saying ' at jdk.proxy2/jdk.proxy2.$Proxy170.deleteById(Unknown Source) ' (this is the first line after pointing to my own code ... nothing else don't seem to be any more descriptive). I can not find anything helpful to figure out what this means.

Setup for the test class looks like this.

@SpringBootTest
@TestInstance(Lifecycle.PER_CLASS)
public class DiaryEntryServiceTest extends MockAuthenticationHelper {
  @Inject
  private EntityCrudRepository repo;
  @BeforeAll
  public void setUp() {
    var created = this.repo.save(new MyEntity());
    assertNotNull(created);
    this.entryId = created.getId();
    assertTrue(this.entryId > 0, "The new id is expected to be set by JPA");
  }

  @AfterAll
  public void tearDown() {
    this.repo.deleteById(this.entryId);
  }

  @Test
  public void dummy() {}
}

The entity is created into the database as supposed to, but the deletion fails at tearDown with the mentioned exception found from the stackTrace.

The full stackTrace is here, maybe there is something I do not get or miss?

java.lang.NullPointerException
at java.base/java.lang.Class.isAssignableFrom(Native Method)
at com.vladmihalcea.hibernate.type.json.internal.JsonTypeDescriptor.fromString(JsonTypeDescriptor.java:104)
at com.vladmihalcea.hibernate.type.json.internal.JsonTypeDescriptor.wrap(JsonTypeDescriptor.java:165)
at com.vladmihalcea.hibernate.type.json.internal.AbstractJsonSqlTypeDescriptor$1.doExtract(AbstractJsonSqlTypeDescriptor.java:34)
at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:47)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:257)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:253)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:243)
at org.hibernate.type.AbstractStandardBasicType.hydrate(AbstractStandardBasicType.java:329)
at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:3214)
at org.hibernate.persister.entity.Loadable.hydrate(Loadable.java:94)
at org.hibernate.loader.plan.exec.process.internal.EntityReferenceInitializerImpl.loadFromResultSet(EntityReferenceInitializerImpl.java:342)
at org.hibernate.loader.plan.exec.process.internal.EntityReferenceInitializerImpl.hydrateEntityState(EntityReferenceInitializerImpl.java:269)
at org.hibernate.loader.plan.exec.process.internal.AbstractRowReader.readRow(AbstractRowReader.java:80)
at org.hibernate.loader.plan.exec.internal.EntityLoadQueryDetails$EntityLoaderRowReader.readRow(EntityLoadQueryDetails.java:288)
at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractRows(ResultSetProcessorImpl.java:157)
at org.hibernate.loader.plan.exec.process.internal.ResultSetProcessorImpl.extractResults(ResultSetProcessorImpl.java:94)
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:105)
at org.hibernate.loader.entity.plan.AbstractLoadPlanBasedEntityLoader.load(AbstractLoadPlanBasedEntityLoader.java:285)
at org.hibernate.persister.entity.AbstractEntityPersister.doLoad(AbstractEntityPersister.java:4521)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:4511)
at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:571)
at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:539)
at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:208)
at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:327)
at org.hibernate.event.internal.DefaultLoadEventListener.doOnLoad(DefaultLoadEventListener.java:108)
at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:74)
at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:118)
at org.hibernate.internal.SessionImpl.fireLoadNoChecks(SessionImpl.java:1231)
at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1220)
at org.hibernate.internal.SessionImpl.access$2100(SessionImpl.java:202)
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.doLoad(SessionImpl.java:2835)
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.lambda$load$1(SessionImpl.java:2812)
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.perform(SessionImpl.java:2768)
at org.hibernate.internal.SessionImpl$IdentifierLoadAccessImpl.load(SessionImpl.java:2812)
at org.hibernate.internal.SessionImpl.find(SessionImpl.java:3400)
at org.hibernate.internal.SessionImpl.find(SessionImpl.java:3367)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:311)
at jdk.proxy2/jdk.proxy2.$Proxy155.find(Unknown Source)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findById(SimpleJpaRepository.java:322)
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.deleteById(SimpleJpaRepository.java:168)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker$RepositoryFragmentMethodInvoker.lambda$new$0(RepositoryMethodInvoker.java:289)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:137)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:121)
at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:529)
at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:285)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:639)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:163)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:138)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:174)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215)
at jdk.proxy2/jdk.proxy2.$Proxy170.deleteById(Unknown Source)
at my.project.ServiceTest.tearDown(ServiceTest.java:48) **<< The row number of the tearDown**
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:725)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:149)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptLifecycleMethod(TimeoutExtension.java:126)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptAfterAllMethod(TimeoutExtension.java:116)
at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeAfterAllMethods$13(ClassBasedTestDescriptor.java:425)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeAfterAllMethods$14(ClassBasedTestDescriptor.java:423)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at java.base/java.util.Collections$UnmodifiableCollection.forEach(Collections.java:1087)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeAfterAllMethods(ClassBasedTestDescriptor.java:423)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.after(ClassBasedTestDescriptor.java:225)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.after(ClassBasedTestDescriptor.java:80)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:161)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:161)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:107)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:114)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:95)
at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:91)
at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:60)
at org.eclipse.jdt.internal.junit5.runner.JUnit5TestReference.run(JUnit5TestReference.java:98)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:40)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:529)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:756)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:452)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:210)

What makes this more puzzling is that I have a test that adds 10 (or more) entries and then deletes them in the same test (via the service class actually tested). And that actually works fine if the 'tearDown' method is commented out. Essentially the service uses the same crud repository as the 'tearDown' does.

The service methods use the @org.springframework.transaction.annotation.Transactional ' annotation and I have tried this also for the test class and for both (all) of the class methods.

The entity uses a sequence generation for the Id and it has a json-type field (The data persisted seems to have the Object correctly).

The question is (if unclear). What does that 'Unknown source' mean? ... or does anyone have any idea what else could be causing the problem?

Answer 1

This first part did not resolve everything (see update ), but at least I got a different exception which was more understandable. I was missing some configuration to use the json column at the entity. The entity class needs to have the following configuration before the class initializer:

@Entity
@Table(name="my_entity")
@TypeDefs({ @TypeDef(name = "json", typeClass = JsonStringType.class),
@TypeDef(name = "jsonb", typeClass = JsonBinaryType.class) })
public class MyEntity {
    @Id
    public long id; 
    @Type(type = "jsonb") // Postgreql doesn't seem to like 'json', but 'jsonb' works
    @Column(columnDefinition = "jsonb") // Postgreql doesn't seem to like 'json', but 'jsonb' works
    public MyJsonObject data;
 }

The postgresql table is done like this.

CREATE TABLE my_entity(
  id BIGINT PRIMARY KEY NOT NULL,
  data JSON NOT NULL
);

This is needed in pom.xml to use the hibernate Types.

<dependency>
    <groupId>com.vladmihalcea</groupId>
    <artifactId>hibernate-types-55</artifactId>
    <version>2.16.2</version>
</dependency>

Seems I overlooked the need of displaying the entity structure with original question. It would had been easy to guess some configuration was missing or wrong unless the insert wouldn't had worked.

// UPDATE
The final error I got was because postgresql does not seem to like ' @TypeDef(name = "json", typeClass = JsonStringType.class) ' so omitting this type option and using only ' jsonb ' for type seems to do the work. (Updated the entity example)

Found the hint from this SO-post: ERROR: column is of type json but expression is of type character varying in Hibernate