HHH-15423 @Any discriminated association fails to be implicitly fetched due to UnsupportedOperationException

hibernate-core/src/main/java/org/hibernate/query/results/Builders.java

@@ -14,6 +14,7 @@ import jakarta.persistence.metamodel.EntityType;
 import jakarta.persistence.metamodel.SingularAttribute;
 
 import org.hibernate.LockMode;
+import org.hibernate.metamodel.mapping.internal.DiscriminatedAssociationAttributeMapping;
 import org.hibernate.query.NativeQuery;
 import org.hibernate.NotYetImplementedFor6Exception;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
@@ -26,6 +27,7 @@ import org.hibernate.metamodel.mapping.SingularAttributeMapping;
 import org.hibernate.metamodel.mapping.internal.EntityCollectionPart;
 import org.hibernate.metamodel.mapping.internal.ToOneAttributeMapping;
 import org.hibernate.persister.entity.EntityPersister;
+import org.hibernate.query.results.implicit.ImplicitFetchBuilderDiscriminatedAssociation;
 import org.hibernate.spi.NavigablePath;
 import org.hibernate.query.internal.ResultSetMappingResolutionContext;
 import org.hibernate.query.results.dynamic.DynamicResultBuilderAttribute;
@@ -276,6 +278,15 @@ public class Builders {
 			return new ImplicitFetchBuilderEntityPart( fetchPath, (EntityCollectionPart) fetchable );
 		}
 
+		if ( fetchable instanceof DiscriminatedAssociationAttributeMapping ) {
+			return new ImplicitFetchBuilderDiscriminatedAssociation(
+					fetchPath,
+					(DiscriminatedAssociationAttributeMapping) fetchable,
+					creationState
+			);
+		}
+
+
 		throw new UnsupportedOperationException();
 	}
 }

hibernate-core/src/main/java/org/hibernate/query/results/implicit/ImplicitFetchBuilderDiscriminatedAssociation.java

@@ -0,0 +1,107 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.query.results.implicit;
+
+import java.util.function.BiFunction;
+
+import org.hibernate.metamodel.mapping.internal.DiscriminatedAssociationAttributeMapping;
+import org.hibernate.query.results.DomainResultCreationStateImpl;
+import org.hibernate.query.results.FetchBuilder;
+import org.hibernate.query.results.dynamic.DynamicFetchBuilderLegacy;
+import org.hibernate.spi.NavigablePath;
+import org.hibernate.sql.ast.SqlAstJoinType;
+import org.hibernate.sql.ast.tree.from.TableGroup;
+import org.hibernate.sql.ast.tree.from.TableGroupJoin;
+import org.hibernate.sql.results.graph.DomainResultCreationState;
+import org.hibernate.sql.results.graph.Fetch;
+import org.hibernate.sql.results.graph.FetchParent;
+import org.hibernate.sql.results.jdbc.spi.JdbcValuesMetadata;
+
+import static org.hibernate.query.results.ResultsHelper.impl;
+
+public class ImplicitFetchBuilderDiscriminatedAssociation implements ImplicitFetchBuilder {
+	private final NavigablePath fetchPath;
+	private final DiscriminatedAssociationAttributeMapping fetchable;
+
+	public ImplicitFetchBuilderDiscriminatedAssociation(
+			NavigablePath fetchPath,
+			DiscriminatedAssociationAttributeMapping fetchable,
+			DomainResultCreationState creationState) {
+		this.fetchPath = fetchPath;
+		this.fetchable = fetchable;
+	}
+
+	@Override
+	public FetchBuilder cacheKeyInstance() {
+		return this;
+	}
+
+	@Override
+	public Fetch buildFetch(
+			FetchParent parent,
+			NavigablePath fetchPath,
+			JdbcValuesMetadata jdbcResultsMetadata,
+			BiFunction<String, String, DynamicFetchBuilderLegacy> legacyFetchResolver,
+			DomainResultCreationState creationState) {
+		final DomainResultCreationStateImpl creationStateImpl = impl( creationState );
+
+		creationStateImpl.getFromClauseAccess().resolveTableGroup(
+				fetchPath,
+				navigablePath -> {
+					final TableGroup parentTableGroup = creationStateImpl
+							.getFromClauseAccess()
+							.getTableGroup( parent.getNavigablePath() );
+					final TableGroupJoin tableGroupJoin = fetchable.createTableGroupJoin(
+							fetchPath,
+							parentTableGroup,
+							null,
+							SqlAstJoinType.INNER,
+							true,
+							false,
+							creationStateImpl
+					);
+					parentTableGroup.addTableGroupJoin( tableGroupJoin );
+					return tableGroupJoin.getJoinedGroup();
+				}
+		);
+		return parent.generateFetchableFetch(
+				fetchable,
+				fetchPath,
+				fetchable.getTiming(),
+				false,
+				null,
+				creationState
+		);
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if ( this == o ) {
+			return true;
+		}
+		if ( o == null || getClass() != o.getClass() ) {
+			return false;
+		}
+
+		final ImplicitFetchBuilderDiscriminatedAssociation that = (ImplicitFetchBuilderDiscriminatedAssociation) o;
+		return fetchPath.equals( that.fetchPath )
+				&& fetchable.equals( that.fetchable );
+	}
+
+	@Override
+	public int hashCode() {
+		int result = fetchPath.hashCode();
+		result = 31 * result + fetchable.hashCode();
+		return result;
+	}
+
+	@Override
+	public String toString() {
+		return "ImplicitFetchBuilderDiscriminatedAssociation(" + fetchPath + ")";
+	}
+
+}

hibernate-core/src/main/java/org/hibernate/query/results/implicit/ImplicitFetchBuilderPlural.java

@@ -48,7 +48,6 @@ public class ImplicitFetchBuilderPlural implements ImplicitFetchBuilder {
 			JdbcValuesMetadata jdbcResultsMetadata,
 			BiFunction<String, String, DynamicFetchBuilderLegacy> legacyFetchResolver,
 			DomainResultCreationState creationState) {
-		final DomainResultCreationStateImpl creationStateImpl = impl( creationState );
 
 		final Fetch fetch = parent.generateFetchableFetch(
 				fetchable,