HHH-18439 Account for null values in query cache hit

Also, solve an assertion error in query result type check when selecting `null` literals

Author: mbellade

hibernate-core/src/main/java/org/hibernate/query/sqm/internal/SqmUtil.java

@@ -1094,7 +1094,10 @@ protected static void verifyResultType(Class<?> resultClass, @Nullable SqmExpres
 		}
 
 		final JavaType<?> selectionExpressibleJavaType = selectionExpressible.getExpressibleJavaType();
-		assert selectionExpressibleJavaType != null;
+		if ( selectionExpressibleJavaType == null ) {
+			// nothing we can validate
+			return;
+		}
 
 		final Class<?> selectionExpressibleJavaTypeClass = selectionExpressibleJavaType.getJavaTypeClass();
 		if ( selectionExpressibleJavaTypeClass != Object.class ) {
@@ -1103,7 +1106,7 @@ protected static void verifyResultType(Class<?> resultClass, @Nullable SqmExpres
 				return;
 			}
 
-			if ( selectionExpressibleJavaType instanceof PrimitiveJavaType<?> primitiveJavaType ) {
+			if ( selectionExpressibleJavaType instanceof final PrimitiveJavaType<?> primitiveJavaType ) {
 				if ( primitiveJavaType.getPrimitiveClass() == resultClass ) {
 					return;
 				}

hibernate-core/src/main/java/org/hibernate/sql/results/jdbc/internal/JdbcValuesCacheHit.java

@@ -176,12 +176,12 @@ public Object getCurrentRowValue(int valueIndex) {
 		if ( valueIndexesToCacheIndexes == null ) {
 			return ( (Object[]) row )[valueIndex];
 		}
-		else if ( row.getClass() != Object[].class ) {
-			assert valueIndexesToCacheIndexes[valueIndex] == 0;
-			return row;
+		else if ( row instanceof Object[] ) {
+			return ( (Object[]) row )[valueIndexesToCacheIndexes[valueIndex]];
 		}
 		else {
-			return ( (Object[]) row )[valueIndexesToCacheIndexes[valueIndex]];
+			assert valueIndexesToCacheIndexes[valueIndex] == 0;
+			return row;
 		}
 	}