Message Title

I am attempting to convert my @Any and @ManyToAny discriminator definitions into meta annotations and I’m also running into problems. The example in the documentation does not provide an example of the “correct” meta annotation. So, I pieced together this thing:

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD, ElementType.TYPE})
@AnyDiscriminator(DiscriminatorType.STRING)
@AnyDiscriminatorValue(discriminator = "S", entity = StringProperty.class)
@AnyDiscriminatorValue(discriminator = "I", entity = IntegerProperty.class)
@AnyKeyJavaClass(Long.class)
public @interface PropertyDiscriminator {

}

java.lang.AssertionError
	at org.hibernate.metamodel.mapping.internal.DiscriminatedAssociationMapping$AnyResultAssembler.assemble(DiscriminatedAssociationMapping.java:571)
	at org.hibernate.sql.results.graph.DomainResultAssembler.assemble(DomainResultAssembler.java:33)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.extractConcreteTypeStateValues(AbstractEntityInitializer.java:1053)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeEntityInstance(AbstractEntityInitializer.java:829)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeEntity(AbstractEntityInitializer.java:804)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeInstance(AbstractEntityInitializer.java:790)
	at org.hibernate.sql.results.internal.InitializersList.initializeInstance(InitializersList.java:70)
	at org.hibernate.sql.results.internal.StandardRowReader.coordinateInitializers(StandardRowReader.java:111)
	at org.hibernate.sql.results.internal.StandardRowReader.readRow(StandardRowReader.java:87)
	at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:185)
	at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:33)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.doExecuteQuery(JdbcSelectExecutorStandardImpl.java:361)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.executeQuery(JdbcSelectExecutorStandardImpl.java:168)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.list(JdbcSelectExecutorStandardImpl.java:93)
	at org.hibernate.sql.exec.spi.JdbcSelectExecutor.list(JdbcSelectExecutor.java:31)
	at org.hibernate.loader.ast.internal.SingleIdLoadPlan.load(SingleIdLoadPlan.java:146)
	at org.hibernate.loader.ast.internal.SingleIdLoadPlan.load(SingleIdLoadPlan.java:118)
	at org.hibernate.loader.ast.internal.SingleIdEntityLoaderStandardImpl.load(SingleIdEntityLoaderStandardImpl.java:73)
	at org.hibernate.persister.entity.AbstractEntityPersister.doLoad(AbstractEntityPersister.java:3481)
	at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3471)
	at org.hibernate.event.internal.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:581)
	at org.hibernate.event.internal.DefaultLoadEventListener.loadFromCacheOrDatasource(DefaultLoadEventListener.java:567)
	at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:536)
	at org.hibernate.event.internal.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:529)
	at org.hibernate.event.internal.DefaultLoadEventListener.load(DefaultLoadEventListener.java:202)
	at org.hibernate.event.internal.DefaultLoadEventListener.loadWithRegularProxy(DefaultLoadEventListener.java:282)
	at org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:237)
	at org.hibernate.event.internal.DefaultLoadEventListener.doOnLoad(DefaultLoadEventListener.java:106)
	at org.hibernate.event.internal.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:78)
	at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:138)
	at org.hibernate.internal.SessionImpl.fireLoadNoChecks(SessionImpl.java:1231)
	at org.hibernate.internal.SessionImpl.fireLoad(SessionImpl.java:1219)
	at org.hibernate.loader.internal.IdentifierLoadAccessImpl.doLoad(IdentifierLoadAccessImpl.java:194)
	at org.hibernate.loader.internal.IdentifierLoadAccessImpl.lambda$load$1(IdentifierLoadAccessImpl.java:160)
	at org.hibernate.loader.internal.IdentifierLoadAccessImpl.perform(IdentifierLoadAccessImpl.java:107)
	at org.hibernate.loader.internal.IdentifierLoadAccessImpl.load(IdentifierLoadAccessImpl.java:160)
	at org.hibernate.internal.SessionImpl.find(SessionImpl.java:2406)
	at org.hibernate.internal.SessionImpl.find(SessionImpl.java:2372)
	at com.example.hibernatepolymorph.HibernatePolymorphApplicationTests.retrieve(HibernatePolymorphApplicationTests.java:137)
	at com.example.hibernatepolymorph.HibernatePolymorphApplicationTests.createPropertyHolder(HibernatePolymorphApplicationTests.java:70)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:727)
	at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
	at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:156)
	at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:147)
	at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:86)
	at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(InterceptingExecutableInvoker.java:103)
	at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.lambda$invoke$0(InterceptingExecutableInvoker.java:93)
	at org.junit.jupiter.engine.execution.InvocationInterceptorChain$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.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:92)
	at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:86)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7(TestMethodTestDescriptor.java:217)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:213)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:138)
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:68)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:151)
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$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)
...

When trying to execute a findAll() on a Spring Boot repository, it throws things like this:

java.lang.NullPointerException: Cannot invoke "org.hibernate.metamodel.mapping.EntityMappingType.getEntityName()" because "entityMapping" is null
	at org.hibernate.metamodel.mapping.internal.DiscriminatedAssociationMapping$AnyResultAssembler.assemble(DiscriminatedAssociationMapping.java:581)
	at org.hibernate.sql.results.graph.DomainResultAssembler.assemble(DomainResultAssembler.java:33)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.extractConcreteTypeStateValues(AbstractEntityInitializer.java:1029)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeEntityInstance(AbstractEntityInitializer.java:805)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeEntity(AbstractEntityInitializer.java:780)
	at org.hibernate.sql.results.graph.entity.AbstractEntityInitializer.initializeInstance(AbstractEntityInitializer.java:766)
	at org.hibernate.sql.results.internal.InitializersList.initializeInstance(InitializersList.java:70)
	at org.hibernate.sql.results.internal.StandardRowReader.coordinateInitializers(StandardRowReader.java:111)
	at org.hibernate.sql.results.internal.StandardRowReader.readRow(StandardRowReader.java:87)
	at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:199)
	at org.hibernate.sql.results.spi.ListResultsConsumer.consume(ListResultsConsumer.java:33)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.doExecuteQuery(JdbcSelectExecutorStandardImpl.java:362)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.executeQuery(JdbcSelectExecutorStandardImpl.java:168)
	at org.hibernate.sql.exec.internal.JdbcSelectExecutorStandardImpl.list(JdbcSelectExecutorStandardImpl.java:93)
	at org.hibernate.sql.exec.spi.JdbcSelectExecutor.list(JdbcSelectExecutor.java:31)
	at org.hibernate.query.sqm.internal.ConcreteSqmSelectQueryPlan.lambda$new$0(ConcreteSqmSelectQueryPlan.java:109)
	at org.hibernate.query.sqm.internal.ConcreteSqmSelectQueryPlan.withCacheableSqmInterpretation(ConcreteSqmSelectQueryPlan.java:302)
	at org.hibernate.query.sqm.internal.ConcreteSqmSelectQueryPlan.performList(ConcreteSqmSelectQueryPlan.java:243)
	at org.hibernate.query.sqm.internal.QuerySqmImpl.doList(QuerySqmImpl.java:518)
	at org.hibernate.query.spi.AbstractSelectionQuery.list(AbstractSelectionQuery.java:367)
	at org.hibernate.query.Query.getResultList(Query.java:119)
	at org.springframework.data.jpa.repository.support.SimpleJpaRepository.readPage(SimpleJpaRepository.java:716)
	at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:474)
	at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:451)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
...

If I replace the meta annotation with the regular @Any… annotations, everything works fine. Am I creating the meta annotation correctly? Or is this something we should not use yet? If so and this gets fixed, can we get an example meta annotation added to the documentation?