HHH-18582 Mapping array of arrays with @JdbcTypeCode(SqlTypes.ARRAY) causes NPE

hibernate-core/src/main/java/org/hibernate/type/BasicTypeRegistry.java

@@ -11,6 +11,7 @@
 
 import org.hibernate.HibernateException;
 import org.hibernate.Internal;
+import org.hibernate.MappingException;
 import org.hibernate.internal.CoreLogging;
 import org.hibernate.internal.CoreMessageLogger;
 import org.hibernate.internal.util.StringHelper;
@@ -156,16 +157,24 @@ private <J> BasicType<J> resolvedType(JavaType<J> javaType, JdbcType jdbcType) {
 	}
 
 	private <E> BasicType<?> resolvedType(ArrayJdbcType arrayType, BasicPluralJavaType<E> castPluralJavaType) {
+		final BasicType<E> elementType = resolve( castPluralJavaType.getElementJavaType(), arrayType.getElementJdbcType() );
 		final BasicType<?> resolvedType = castPluralJavaType.resolveType(
 				typeConfiguration,
 				typeConfiguration.getCurrentBaseSqlTypeIndicators().getDialect(),
-				resolve( castPluralJavaType.getElementJavaType(), arrayType.getElementJdbcType() ),
+				elementType,
 				null,
 				typeConfiguration.getCurrentBaseSqlTypeIndicators()
 		);
 		if ( resolvedType instanceof BasicPluralType<?,?> ) {
 			register( resolvedType );
 		}
+		else if ( resolvedType == null ) {
+			final Class<?> elementJavaTypeClass = elementType.getJavaTypeDescriptor().getJavaTypeClass();
+			if ( elementJavaTypeClass != null && elementJavaTypeClass.isArray() && elementJavaTypeClass != byte[].class ) {
+				// No support for nested arrays, except for byte[][]
+				throw new MappingException( "Nested arrays (with the exception of byte[][]) are not supported" );
+			}
+		}
 		return resolvedType;
 	}
 

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/array/ArrayOfArraysTest.java

@@ -0,0 +1,95 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.mapping.array;
+
+import org.hibernate.MappingException;
+import org.hibernate.annotations.JdbcTypeCode;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.cfg.Configuration;
+import org.hibernate.type.SqlTypes;
+
+import org.hibernate.testing.orm.junit.DialectFeatureChecks;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.RequiresDialectFeature;
+import org.hibernate.testing.orm.junit.ServiceRegistry;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.hibernate.testing.orm.junit.Setting;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import org.assertj.core.data.Index;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+/**
+ * @author Marco Belladelli
+ */
+@RequiresDialectFeature( feature = DialectFeatureChecks.SupportsStandardArrays.class )
+public class ArrayOfArraysTest {
+	@DomainModel( annotatedClasses = ArrayOfArraysTest.EntityWithDoubleByteArray.class )
+	@SessionFactory
+	@ServiceRegistry( settings = @Setting( name = AvailableSettings.HBM2DDL_AUTO, value = "create-drop" ) )
+	@Test
+	public void testDoubleByteArrayWorks(SessionFactoryScope scope) {
+		final Long id = scope.fromTransaction( session -> {
+			final EntityWithDoubleByteArray entity = new EntityWithDoubleByteArray();
+			entity.setByteArray( new byte[][] { new byte[] { 1 } } );
+			session.persist( entity );
+			return entity.getId();
+		} );
+		scope.inSession( session -> {
+			final byte[][] byteArray = session.find( EntityWithDoubleByteArray.class, id ).getByteArray();
+			assertThat( byteArray ).hasDimensions( 1, 1 ).contains( new byte[] { 1 }, Index.atIndex( 0 ) );
+		} );
+	}
+
+	@Test
+	public void testDoubleIntegerArrayThrows() {
+		final Configuration cfg = new Configuration();
+		cfg.addAnnotatedClass( EntityWithDoubleIntegerArray.class );
+		try (final org.hibernate.SessionFactory sf = cfg.buildSessionFactory()) {
+			fail( "Expecting Integer[][] to trigger exception as non-byte multidimensional arrays are not supported" );
+		}
+		catch (Exception e) {
+			assertThat( e ).isInstanceOf( MappingException.class ).hasMessage( "Nested arrays (with the exception of byte[][]) are not supported" );
+		}
+	}
+
+	@Entity( name = "EntityWithDoubleByteArray" )
+	static class EntityWithDoubleByteArray {
+		@Id
+		@GeneratedValue
+		private Long id;
+
+		@JdbcTypeCode( SqlTypes.ARRAY )
+		private byte[][] byteArray;
+
+		public Long getId() {
+			return id;
+		}
+
+		public byte[][] getByteArray() {
+			return byteArray;
+		}
+
+		public void setByteArray(byte[][] byteArray) {
+			this.byteArray = byteArray;
+		}
+	}
+
+	@Entity( name = "EntityWithDoubleIntegerArray" )
+	static class EntityWithDoubleIntegerArray {
+		@Id
+		@GeneratedValue
+		private Long id;
+
+		@JdbcTypeCode( SqlTypes.ARRAY )
+		private Integer[][] integers;
+	}
+}