Refine wrapping rules for copy and constructor usage.

pom.xml

@@ -127,6 +127,12 @@
 			<scope>test</scope>
 		</dependency>
 
+		<dependency>
+			<groupId>org.jetbrains.kotlin</groupId>
+			<artifactId>kotlin-maven-plugin</artifactId>
+			<version>${kotlin}</version>
+		</dependency>
+
 		<!--  RxJava -->
 
 		<dependency>

src/main/java/org/springframework/data/mapping/model/BeanWrapper.java

@@ -190,7 +190,7 @@ private static <T> Map<KParameter, Object> getCallArgs(KCallable<?> callable, Pe
 				if (parameter.getKind() == Kind.VALUE && parameter.getName() != null
 						&& parameter.getName().equals(property.getName())) {
 
-					args.put(parameter, KotlinValueUtils.getValueHierarchy(parameter).wrap(value));
+					args.put(parameter, KotlinValueUtils.getCopyValueHierarchy(parameter).wrap(value));
 				}
 			}
 			return args;

src/main/java/org/springframework/data/mapping/model/ClassGeneratingPropertyAccessorFactory.java

@@ -1488,7 +1488,7 @@ public void setProperty(PersistentProperty<?> property, @Nullable Object value)
 		 * @param property the persistent property to inspect.
 		 * @return a wrapper function to wrap a value class component into the hierarchy of value classes or
 		 *         {@link Function#identity()} if wrapping is not necessary.
-		 * @see KotlinValueUtils#getValueHierarchy(Class)
+		 * @see KotlinValueUtils#getCopyValueHierarchy(KParameter)
 		 */
 		static Function<Object, Object> getWrapper(PersistentProperty<?> property) {
 
@@ -1506,7 +1506,7 @@ static Function<Object, Object> getWrapper(PersistentProperty<?> property) {
 						.filter(kf -> kf.getName().equals(property.getName())) //
 						.findFirst();
 
-				ValueBoxing vh = kParameter.map(KotlinValueUtils::getValueHierarchy).orElse(null);
+				ValueBoxing vh = kParameter.map(KotlinValueUtils::getCopyValueHierarchy).orElse(null);
 				KotlinCopyByProperty kotlinCopyByProperty = copyMethod.forProperty(property).get();
 				Method copy = copyMethod.getSyntheticCopyMethod();
 

src/main/java/org/springframework/data/mapping/model/InstanceCreatorMetadataDiscoverer.java

@@ -15,6 +15,11 @@
  */
 package org.springframework.data.mapping.model;
 
+import kotlin.jvm.JvmClassMappingKt;
+import kotlin.reflect.KCallable;
+import kotlin.reflect.KClass;
+import kotlin.reflect.KProperty;
+
 import java.lang.annotation.Annotation;
 import java.lang.reflect.AnnotatedElement;
 import java.lang.reflect.Constructor;
@@ -24,6 +29,7 @@
 import java.util.List;
 
 import org.springframework.core.DefaultParameterNameDiscoverer;
+import org.springframework.core.KotlinDetector;
 import org.springframework.core.ParameterNameDiscoverer;
 import org.springframework.core.annotation.MergedAnnotations;
 import org.springframework.data.annotation.PersistenceCreator;
@@ -55,7 +61,8 @@ class InstanceCreatorMetadataDiscoverer {
 	 * @return
 	 */
 	@Nullable
-	public static <T, P extends PersistentProperty<P>> InstanceCreatorMetadata<P> discover(PersistentEntity<T, P> entity) {
+	public static <T, P extends PersistentProperty<P>> InstanceCreatorMetadata<P> discover(
+			PersistentEntity<T, P> entity) {
 
 		Constructor<?>[] declaredConstructors = entity.getType().getDeclaredConstructors();
 		Method[] declaredMethods = entity.getType().getDeclaredMethods();
@@ -78,6 +85,34 @@ public static <T, P extends PersistentProperty<P>> InstanceCreatorMetadata<P> di
 			}
 		}
 
+		if (KotlinDetector.isKotlinReflectPresent() && KotlinDetector.isKotlinType(entity.getType())) {
+
+			KClass<?> kClass = JvmClassMappingKt.getKotlinClass(entity.getType());
+			// We use box-impl as factory for classes.
+			if (kClass.isValue()) {
+
+				String propertyName = "";
+				for (KCallable<?> member : kClass.getMembers()) {
+					if (member instanceof KProperty<?>) {
+						propertyName = member.getName();
+						break;
+					}
+				}
+
+				for (Method declaredMethod : entity.getType().getDeclaredMethods()) {
+					if (declaredMethod.getName().equals("box-impl") && declaredMethod.isSynthetic()
+							&& declaredMethod.getParameterCount() == 1) {
+
+						Annotation[][] parameterAnnotations = declaredMethod.getParameterAnnotations();
+						List<TypeInformation<?>> types = entity.getTypeInformation().getParameterTypes(declaredMethod);
+
+						return new FactoryMethod<>(declaredMethod,
+								new Parameter<>(propertyName, (TypeInformation) types.get(0), parameterAnnotations[0], entity));
+					}
+				}
+			}
+		}
+
 		return PreferredConstructorDiscoverer.discover(entity);
 	}
 

src/main/java/org/springframework/data/mapping/model/KotlinInstantiationDelegate.java

@@ -67,7 +67,7 @@ public KotlinInstantiationDelegate(PreferredConstructor<?, ?> preferredConstruct
 
 		for (KParameter kParameter : kParameters) {
 
-			ValueBoxing valueBoxing = KotlinValueUtils.getValueHierarchy(kParameter);
+			ValueBoxing valueBoxing = KotlinValueUtils.getConstructorValueHierarchy(kParameter);
 			wrappers.add(valueBoxing::wrap);
 		}
 	}
@@ -242,9 +242,9 @@ static boolean parametersMatch(java.lang.reflect.Parameter constructorParameter,
 		}
 
 		// candidate can be also a wrapper
+		Class<?> componentOrWrapperType = KotlinValueUtils.getConstructorValueHierarchy(candidateParameter.getType())
+				.getActualType();
 
-		Class<?> componentType = KotlinValueUtils.getValueHierarchy(candidateParameter.getType()).getActualType();
-
-		return constructorParameter.getType().equals(componentType);
+		return constructorParameter.getType().equals(componentOrWrapperType);
 	}
 }