Properties annotated with @MappedCollection cannot be of type java.util.Set anymore

[erki]

Using the latest RC-Version of Spring-Boot (3.2.0-RC2) that ships with spring-data-jdbc 3.2.0-RC1 I've noticed that it isn't possible anymore to use @MappedCollection on entity properties that are of type java.util.Set.

@Table("aggregate")
@RequiredArgsConstructor
@Getter
public class Aggregate implements Persistable<String> {

    @Id
    private final String id;

    @MappedCollection(idColumn = "aggregate_id")
    private final Set<ChildEntity> children;
}

This results in the following exception when trying to load such an aggregate from the database:

org.springframework.data.mapping.model.MappingInstantiationException: Failed to instantiate com.example.springdatajdbcbug.Aggregate using constructor public com.example.springdatajdbcbug.Aggregate(java.lang.String,java.util.Set) with arguments 1,[com.example.springdatajdbcbug.ChildEntity@578198d9, com.example.springdatajdbcbug.ChildEntity@4deca78]

	at org.springframework.data.mapping.model.ClassGeneratingEntityInstantiator$EntityInstantiatorAdapter.createInstance(ClassGeneratingEntityInstantiator.java:278)
	at org.springframework.data.mapping.model.ClassGeneratingEntityInstantiator.createInstance(ClassGeneratingEntityInstantiator.java:98)
	at org.springframework.data.relational.core.conversion.MappingRelationalConverter.read(MappingRelationalConverter.java:454)
	at org.springframework.data.relational.core.conversion.MappingRelationalConverter.readAggregate(MappingRelationalConverter.java:348)
	at org.springframework.data.relational.core.conversion.MappingRelationalConverter.readAggregate(MappingRelationalConverter.java:311)
	at org.springframework.data.jdbc.core.convert.MappingJdbcConverter.readAndResolve(MappingJdbcConverter.java:287)
	at org.springframework.data.jdbc.core.convert.JdbcConverter.readAndResolve(JdbcConverter.java:106)
	at org.springframework.data.jdbc.core.convert.EntityRowMapper.mapRow(EntityRowMapper.java:82)
	at org.springframework.jdbc.core.RowMapperResultSetExtractor.extractData(RowMapperResultSetExtractor.java:94)
	at org.springframework.jdbc.core.RowMapperResultSetExtractor.extractData(RowMapperResultSetExtractor.java:61)
	at org.springframework.jdbc.core.JdbcTemplate$1.doInPreparedStatement(JdbcTemplate.java:729)
	at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:654)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:719)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:744)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:800)
	at org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate.queryForObject(NamedParameterJdbcTemplate.java:252)
	at org.springframework.data.jdbc.core.convert.DefaultDataAccessStrategy.findById(DefaultDataAccessStrategy.java:268)
	at org.springframework.data.jdbc.core.JdbcAggregateTemplate.findById(JdbcAggregateTemplate.java:290)
	at org.springframework.data.jdbc.repository.support.SimpleJdbcRepository.findById(SimpleJdbcRepository.java:79)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:352)
	at org.springframework.data.repository.core.support.RepositoryMethodInvoker$RepositoryFragmentMethodInvoker.lambda$new$0(RepositoryMethodInvoker.java:277)
	at org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:170)
	at org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:158)
	at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:516)
	at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:285)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:628)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:168)
	at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:143)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)
	at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:385)
	at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:249)
	at jdk.proxy2/jdk.proxy2.$Proxy86.findById(Unknown Source)
	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.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:352)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:196)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
	at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:249)
	at jdk.proxy2/jdk.proxy2.$Proxy86.findById(Unknown Source)
	at com.example.springdatajdbcbug.SpringDataJdbcBugApplicationTests.test(SpringDataJdbcBugApplicationTests.java:24)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
Caused by: java.lang.ClassCastException: class java.util.ArrayList cannot be cast to class java.util.Set (java.util.ArrayList and java.util.Set are in module java.base of loader 'bootstrap')
	at com.example.springdatajdbcbug.Aggregate_Instantiator_nja7yr.newInstance(Unknown Source)
	at org.springframework.data.mapping.model.ClassGeneratingEntityInstantiator$EntityInstantiatorAdapter.createInstance(ClassGeneratingEntityInstantiator.java:276)
	... 58 more

I've set up a small project based on spring-boot 3.2.0-RC2 which can be found here

Using spring-boot 3.1.5 on the same sample project the error does not occur.

[schauder]

Thanks for reporting this. I strongly believe this is a duplicate of #1646.
Could you please confirm by testing a recent Snapshot version?

[erki]

You're right. I just tried with 3.2.0-SNAPSHOT and it seems that this issue is fixed there.

[schauder]

Thanks for confirming this is a duplicate of #1646.