EDIT

/**

 *

 */

package eu.etaxonomy.cdm.persistence.dao.hibernate.common;

import java.lang.reflect.Field;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

import javax.naming.Reference;

import org.apache.commons.lang.UnhandledException;

import org.apache.log4j.Logger;

import org.hibernate.MappingException;

import org.hibernate.Query;

import org.hibernate.Session;

import org.hibernate.internal.SessionFactoryImpl;

import org.hibernate.internal.SessionImpl;

import org.hibernate.metadata.ClassMetadata;

import org.hibernate.metadata.CollectionMetadata;

import org.hibernate.persister.collection.CollectionPersister;

import org.hibernate.persister.collection.OneToManyPersister;

import org.hibernate.persister.entity.AbstractEntityPersister;

import org.hibernate.type.AnyType;

import org.hibernate.type.CollectionType;

import org.hibernate.type.ComponentType;

import org.hibernate.type.EntityType;

import org.hibernate.type.SetType;

import org.hibernate.type.Type;

import eu.etaxonomy.cdm.hibernate.HibernateProxyHelper;

import eu.etaxonomy.cdm.model.agent.TeamOrPersonBase;

import eu.etaxonomy.cdm.model.common.AnnotatableEntity;

import eu.etaxonomy.cdm.model.common.Annotation;

import eu.etaxonomy.cdm.model.common.CdmBase;

import eu.etaxonomy.cdm.model.common.Extension;

import eu.etaxonomy.cdm.model.common.ICdmBase;

import eu.etaxonomy.cdm.model.common.IIntextReferencable;

import eu.etaxonomy.cdm.model.common.IdentifiableEntity;

import eu.etaxonomy.cdm.model.common.Identifier;

import eu.etaxonomy.cdm.model.common.IntextReference;

import eu.etaxonomy.cdm.model.common.Marker;

import eu.etaxonomy.cdm.model.name.TaxonName;

import eu.etaxonomy.cdm.model.name.TaxonNameFactory;

import eu.etaxonomy.cdm.model.taxon.Taxon;

import eu.etaxonomy.cdm.persistence.dao.hibernate.common.CdmGenericDaoImpl.ReferenceHolder;

import eu.etaxonomy.cdm.strategy.merge.ConvertMergeStrategy;

import eu.etaxonomy.cdm.strategy.merge.DefaultMergeStrategy;

import eu.etaxonomy.cdm.strategy.merge.IMergable;

import eu.etaxonomy.cdm.strategy.merge.IMergeStrategy;

import eu.etaxonomy.cdm.strategy.merge.MergeException;

/**

 * @author a.mueller

 */

public class DeduplicationHelper {

	private static final Logger logger = Logger.getLogger(DeduplicationHelper.class);

	private final SessionImpl session;

	private final CdmGenericDaoImpl genericDao;

	protected DeduplicationHelper(SessionImpl session, CdmGenericDaoImpl genericDao){

		this.session = session;

		this.genericDao = genericDao;

	}

	public <T extends CdmBase>  boolean isMergeable(T cdmBase1, T cdmBase2, IMergeStrategy mergeStrategy) {

		if (mergeStrategy == null){

			mergeStrategy = DefaultMergeStrategy.NewInstance(cdmBase1.getClass());

		}

		try {

			checkMergeValid(cdmBase1, cdmBase2, mergeStrategy);

			return true;

		} catch (IllegalArgumentException e) {

			return false;

		} catch (NullPointerException e) {

			return false;

		}

	}

	public <T extends CdmBase>  void merge(T cdmBase1, T cdmBase2, IMergeStrategy mergeStrategy) throws MergeException {

		@SuppressWarnings("unchecked")

		Class<T> clazz = (Class<T>)cdmBase1.getClass();

		@SuppressWarnings("unchecked")

		Class<T> clazz2 = (Class<T>)cdmBase2.getClass();

		if (mergeStrategy == null){

			mergeStrategy = DefaultMergeStrategy.NewInstance(cdmBase1.getClass());

		}

		try {

			//check null and types

			checkMergeValid(cdmBase1, cdmBase2, mergeStrategy);

			//merge objects

			//externel impl

			//internal impl

			Set<ICdmBase> deleteSet = new HashSet<>();

			Set<ICdmBase> cloneSet = new HashSet<>();

			if (cdmBase1 instanceof IMergable){

				IMergable mergable1 = (IMergable)cdmBase1;

				IMergable mergable2 = (IMergable)cdmBase2;

				deleteSet = mergeStrategy.invoke(mergable1, mergable2, cloneSet);

				//session.saveOrUpdate(mergable1);

				//session.flush();

				//((IMergable)cdmBase1).mergeInto(cdmBase2, DefaultMergeStrategy.NewInstance(cdmBase1.getClass()));

			}else{

				//TODO should we better use clazz2 here?

				mergeExternal(cdmBase1, cdmBase2, clazz, session);

			}

			if (cdmBase2.getId() > 0){

				session.saveOrUpdate(cdmBase2);

				session.flush();

				//rearrange references pointing to cdmBase2 to cdmBase1 in future

				reallocateReferences(cdmBase1, cdmBase2, clazz2, cloneSet);

			}

			//remove deleted objects

			//session.delete(null, mergable2, true, null);

			boolean deleteSecond = true;

			if (mergeStrategy instanceof ConvertMergeStrategy) {

			    deleteSecond = ((ConvertMergeStrategy)mergeStrategy).isDeleteSecondObject();

			}

			if(deleteSecond){

			    session.delete(cdmBase2);

			    for (ICdmBase toBeDeleted : deleteSet){

	                logger.debug("Delete " + toBeDeleted);

	                if (toBeDeleted != cdmBase2){

	                    session.delete(toBeDeleted);

	                }

	            }

			}

			//flush

			session.flush();

		} catch (Exception e) {

			e.printStackTrace();

		    throw new MergeException(e);

		}

	}

	/**

	 * Throws an exception if merge is not possible.

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param strategy

	 * @throws IllegalArgumentException

	 * @throws NullPointerException

	 */

	private <T extends CdmBase> void checkMergeValid(T cdmBase1, T cdmBase2, IMergeStrategy strategy)throws IllegalArgumentException, NullPointerException{

		if (cdmBase1 == null || cdmBase2 == null){

			throw new NullPointerException("Merge arguments must not be (null)");

		}

		cdmBase1 = HibernateProxyHelper.deproxy(cdmBase1);

		cdmBase2 = HibernateProxyHelper.deproxy(cdmBase2);

		if (cdmBase1.getClass() != cdmBase2.getClass()){

			boolean reallocationPossible = checkOnlyReallocationAllowed(cdmBase1.getClass(), cdmBase2.getClass());

			if (! reallocationPossible){

				String msg = "Merge not possible for objects of type %s and type %s";

				msg = String.format(msg, cdmBase1.getClass().getSimpleName(), cdmBase2.getClass().getSimpleName());

				throw new IllegalArgumentException(msg);

			}else{

				if (! checkInstancesMergeable(cdmBase1, cdmBase2, strategy)){

					throw new IllegalArgumentException("Object can not be merged into new object as it is referenced in a way that does not allow merging");

				}

			}

		}

	}

	@SuppressWarnings("unchecked")

	private <T extends CdmBase> boolean checkInstancesMergeable(T cdmBase1, T cdmBase2, IMergeStrategy strategy){

		Class<T> clazz2 = (Class<T>)cdmBase2.getClass();

		//FIXME do we need to compute the cloneSet? See #reallocateReferences for comparison

		//this is only a copy from there. Maybe we do not need the cloneSet at all here

		Set<ICdmBase> cloneSet = new HashSet<>();

		Set<ReferenceHolder> holderSet;

		try {

			boolean result = true;

			holderSet = genericDao.getOrMakeHolderSet(clazz2);

			for (ReferenceHolder refHolder: holderSet){

				if (! reallocateByHolderPossible(cdmBase1, cdmBase2, refHolder, cloneSet)){

					return false;

				}

			}

			return result;

		} catch (ClassNotFoundException | NoSuchFieldException | MergeException e) {

			return false;

		}

	}

	/**

	 * Checks if 2 can be merged and reallocation of referencing objects is allowed.

	 * This is <code>true</code> if

	 * classes are same or for some explicit cases like both

	 * inherit form {@link TeamOrPersonBase} or from {@link TaxonName}.

	 * Necessary condition is that both classes are mapped to the same table.

	 *

	 * @param class1

	 * @param class2

	 * @return true if mer

	 */

	private boolean  checkOnlyReallocationAllowed(Class<? extends CdmBase> class1,

			Class<? extends CdmBase> class2) {

		if (class1 == class2){

			return true;

		}else{

			if (classesAssignableFrom(TeamOrPersonBase.class, class1, class2)){

				return true;

			}else if (classesAssignableFrom(TaxonName.class, class1, class2)){

				return true;

			}else{

				return false;

			}

		}

	}

	private boolean classesAssignableFrom(Class<? extends CdmBase> superClass,

			Class<? extends CdmBase> class1, Class<? extends CdmBase> class2) {

		return superClass.isAssignableFrom(class1) && superClass.isAssignableFrom(class2);

	}

	/**

	 * @param <T>

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param clazz

	 * @param sessionFactory

	 * @throws MergeException

	 * @throws ClassNotFoundException

	 * @throws NoSuchFieldException

	 */

	private <T extends CdmBase> void mergeExternal(T cdmBase1, T cdmBase2, Class<T> clazz,

			Session session) throws MergeException {

//		handleAnnotations

		logger.warn("Merge external");

		handleAnnotationsEtc(cdmBase1, cdmBase2, session);

		SessionFactoryImpl sessionFactory = (SessionFactoryImpl) session.getSessionFactory();

//		Map<String, ClassMetadata> allClassMetadata = sessionFactory.getAllClassMetadata();

		//TODO cast

		getCollectionRoles(clazz, sessionFactory);

		TaxonName name1 = TaxonNameFactory.NewBotanicalInstance(null);

		name1.getTaxonBases();

		Type propType = sessionFactory.getReferencedPropertyType(TaxonName.class.getCanonicalName(), "taxonBases");

//		Map<?,?> collMetadata = sessionFactory.getAllCollectionMetadata();

		//roles = sessionFactory.getCollectionRolesByEntityParticipant("eu.etaxonomy.cdm.model.name.BotanicalName");

		CollectionPersister collPersister;

		try {

			collPersister = sessionFactory.getCollectionPersister(TaxonName.class.getCanonicalName()+".annotations");

		} catch (MappingException e) {

		    // TODO Auto-generated catch block

            e.printStackTrace();

		}

//		Statistics statistics = sessionFactory.getStatistics();

		logger.debug("");

		ClassMetadata taxonMetaData = sessionFactory.getClassMetadata(Taxon.class);

		String ename = taxonMetaData.getEntityName();

		try {

			Reference ref = sessionFactory.getReference();

			logger.debug("");

		} catch (Exception e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

		//sessionFactory.get

		ClassMetadata classMetadata = session.getSessionFactory().getClassMetadata(clazz);

		Type[] propertyTypes = classMetadata.getPropertyTypes();

		int propertyNr = 0;

		for (Type propertyType: propertyTypes){

			String propertyName = classMetadata.getPropertyNames()[propertyNr];

			logger.debug(propertyName);

			makeMergeProperty(cdmBase1, cdmBase2, propertyType, propertyName, sessionFactory, false);

			propertyNr++;

		}

		Set<String> collectionRoles;

		if (classMetadata instanceof AbstractEntityPersister){

			AbstractEntityPersister persister = (AbstractEntityPersister)classMetadata;

			String rootName = persister.getRootEntityName();

			collectionRoles = sessionFactory.getCollectionRolesByEntityParticipant(rootName);

			for (String collectionRole : collectionRoles){

				CollectionMetadata collMetadata2 = sessionFactory.getCollectionMetadata(collectionRole);

				String role = collMetadata2.getRole();

				Type elType = collMetadata2.getElementType();

				logger.debug(role);

			}

		}

	}

	/**

	 * @param <T>

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param session

	 */

	private <T> void handleAnnotationsEtc(T cdmBase1, T cdmBase2, Session session) {

		//when handling annotations and other elements linked via @Any an JDBC errors occurs

		//due to the unique column constraint in the association table on the column referencing

		//the annotation.

		//For some reason not delete command is executed for the old collection

		// Hibernate bug ??

		session.flush();  //for debugging

		if (cdmBase1 instanceof AnnotatableEntity){

			copyAnnotatableExtensions(cdmBase1, cdmBase2, session);

		}

		if (cdmBase1 instanceof IdentifiableEntity){

			copyIdentifiableExtensions(cdmBase1, cdmBase2, session);

		}

		session.saveOrUpdate(cdmBase1);

		session.saveOrUpdate(cdmBase2);

		session.flush();

	}

	/**

	 * Clones all annotations and markers of cdmBase2 and

	 * attaches the clones to cdmBase1.

	 * Finally removes all annotations and markers from cdmBase2.

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param session

	 */

	private <T> void copyAnnotatableExtensions(T cdmBase1, T cdmBase2,

			Session session) {

		AnnotatableEntity annotatableEntity1 = (AnnotatableEntity)cdmBase1;

		AnnotatableEntity annotatableEntity2 = (AnnotatableEntity)cdmBase2;

		//annotations

		List<Annotation> removeListAnnotation = new ArrayList<>();

		for (Annotation annotation : annotatableEntity2.getAnnotations()){

			Annotation clone = null;

			try {

				clone = annotation.clone();

			} catch (CloneNotSupportedException e) {

				e.printStackTrace();

			}

			annotatableEntity1.addAnnotation(clone);

			removeListAnnotation.add(annotation);

		}

		for (Annotation annotation : removeListAnnotation){

			annotatableEntity2.removeAnnotation(annotation);

			session.delete(annotation);

		}

		//marker

		List<Marker> removeListMarker = new ArrayList<>();

		for (Marker marker : annotatableEntity2.getMarkers()){

			Marker clone = null;

			try {

				clone = marker.clone();

			} catch (CloneNotSupportedException e) {

				e.printStackTrace();

			}

			annotatableEntity1.addMarker(clone);

			removeListMarker.add(marker);

		}

		for (Marker marker : removeListMarker){

			annotatableEntity2.removeMarker(marker);

			session.delete(marker);

		}

	}

	/**

	 * Clones all extensions of cdmBase2 and

	 * attaches the clones to cdmBase1.

	 * Finally removes all annotations and markers from cdmBase2.

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param session

	 */

	//TODO Why do we not handle credits, rights and sources here

	private <T> void copyIdentifiableExtensions(T cdmBase1, T cdmBase2,

			Session session) {

		IdentifiableEntity<?> identifiableEntity1 = (IdentifiableEntity<?>)cdmBase1;

		IdentifiableEntity<?> identifiableEntity2 = (IdentifiableEntity<?>)cdmBase2;

		//extensions

		List<Extension> removeListExtension = new ArrayList<>();

		for (Extension changeObject : identifiableEntity2.getExtensions()){

			try {

				Extension clone = changeObject.clone();

				identifiableEntity1.addExtension(clone);

				removeListExtension.add(changeObject);

			} catch (CloneNotSupportedException e) {

				throw new RuntimeException("Clone is not yet supported for class " + changeObject.getClass().getName() + " but should.");

			}

		}

		for (Extension removeObject : removeListExtension){

			identifiableEntity2.removeExtension(removeObject);

			session.delete(removeObject);

		}

		//identifiers

		List<Identifier<?>> removeListIdentifier = new ArrayList<>();

		for (Identifier<?> changeObject : identifiableEntity2.getIdentifiers()){

			try {

				Identifier<?> clone = changeObject.clone();

				identifiableEntity1.addIdentifier(clone);

				removeListIdentifier.add(changeObject);

			} catch (CloneNotSupportedException e) {

			    throw new RuntimeException(e);

			}

		}

		for (Identifier<?> removeObject : removeListIdentifier){

			identifiableEntity2.removeIdentifier(removeObject);

			session.delete(removeObject);

		}

	}

	private void reallocateReferences(CdmBase cdmBase1, CdmBase cdmBase2, Class<? extends CdmBase> clazz, Set<ICdmBase> cloneSet){

		try {

			Set<ReferenceHolder> holderSet = genericDao.getOrMakeHolderSet(clazz);

			for (ReferenceHolder refHolder: holderSet){

				reallocateByHolder(cdmBase1, cdmBase2, refHolder, cloneSet);

			}

			return;

		} catch (Exception e) {

			throw new RuntimeException(e);

		}

	}

	/**

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param refHolder

	 * @throws MergeException

	 */

	private boolean reallocateByHolderPossible(CdmBase cdmBase1, CdmBase cdmBase2, ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws MergeException {

		try {

			if (refHolder.isCollection()){

				return reallocateCollectionPossible(cdmBase1, cdmBase2, refHolder, cloneSet);

			}else{

				return reallocateSingleItemPossible(cdmBase1, cdmBase2, refHolder, cloneSet);

			}

		} catch (Exception e) {

			throw new MergeException("Error during reallocation of references to merge object: " + cdmBase2, e);

		}

	}

	/**

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param refHolder

	 * @throws MergeException

	 */

	private void reallocateByHolder(CdmBase cdmBase1, CdmBase cdmBase2, ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws MergeException {

		try {

			if (refHolder.isCollection()){

				reallocateCollection(cdmBase1, cdmBase2, refHolder, cloneSet);

			}else{

				reallocateSingleItem(cdmBase1, cdmBase2, refHolder, cloneSet);

			}

		} catch (Exception e) {

			throw new MergeException("Error during reallocation of references to merge object: " + cdmBase2, e);

		}

	}

	private boolean reallocateCollectionPossible(CdmBase cdmBase1, CdmBase cdmBase2,

			ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws SecurityException, IllegalArgumentException {

		Class<?> targetClass = refHolder.targetClass;

		Class<?> clazz1 = cdmBase1.getClass();

		if (! targetClass.isAssignableFrom(clazz1)){

			//FIXME only do count or hasXXX, we do not need to instantiate objects here

			List<CdmBase> referencingObjects = genericDao.getCdmBasesWithItemInCollection(refHolder.itemClass, refHolder.otherClass, refHolder.propertyName, cdmBase2, null);

			if (! referencingObjects.isEmpty()){

				return false;

			}

		}

		return true;

	}

	/**

	 * @param cdmBase1

	 * @param cdmBase2

	 * @param refHolder

	 * @param cloneSet

	 * @throws MergeException

	 * @throws NoSuchFieldException

	 * @throws SecurityException

	 * @throws IllegalAccessException

	 * @throws IllegalArgumentException

	 * @throws InvocationTargetException

	 */

	private void reallocateCollection(CdmBase cdmBase1, CdmBase cdmBase2,

			ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws MergeException, SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {

		List<CdmBase> list = genericDao.getCdmBasesWithItemInCollection(refHolder.itemClass, refHolder.otherClass, refHolder.propertyName, cdmBase2, null);

		for (CdmBase referencingObject : list){

			Field referencingField = getFieldRecursive(refHolder.otherClass, refHolder.propertyName);

			referencingField.setAccessible(true);

			Object collection = referencingField.get(referencingObject);

			if (! (collection instanceof Collection)){

				throw new MergeException ("Reallocation of collections for collection other than set and list not yet implemented");

			}else if (collection instanceof List){

			    Method replaceMethod = DefaultMergeStrategy.getReplaceMethod(referencingField);

			    replaceMethod.invoke(referencingObject, cdmBase1, cdmBase2);

			}else{

			    Method addMethod = DefaultMergeStrategy.getAddMethod(referencingField, false);

			    Method removeMethod = DefaultMergeStrategy.getAddMethod(referencingField, true);

			    addMethod.invoke(referencingObject, cdmBase1);

			    removeMethod.invoke(referencingObject, cdmBase2);

			}

		}

	}

	private boolean reallocateSingleItemPossible(CdmBase cdmBase1, CdmBase cdmBase2, ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {

		Class<?> targetClass = refHolder.targetClass;

		Class<?> clazz1 = cdmBase1.getClass();

		if (! targetClass.isAssignableFrom(clazz1)){

			//FIXME only do count or hasXXX, we do not need to instantiate objects here

			List<CdmBase> referencingObjects = genericDao.getCdmBasesByFieldAndClass(refHolder.otherClass, refHolder.propertyName, cdmBase2, null);

			if (! referencingObjects.isEmpty()){

				return false;

			}

		}

		return true;

	}

	private void reallocateSingleItem(CdmBase cdmBase1, CdmBase cdmBase2, ReferenceHolder refHolder, Set<ICdmBase> cloneSet) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {

		List<CdmBase> referencingObjects = genericDao.getCdmBasesByFieldAndClass(refHolder.otherClass, refHolder.propertyName, cdmBase2, null);

		for (CdmBase referencingObject : referencingObjects){

			if (!cloneSet.contains(referencingObject)){

		        String className = refHolder.otherClass.getSimpleName();

	            String propertyName = refHolder.propertyName;

		        String hql = " UPDATE " + className + " c "

		                + " SET c."+propertyName+" = :newValue "

		                + " WHERE c.id = :id ";

		        Query query = session.createQuery(hql);

		        query.setEntity("newValue", cdmBase1);

		        query.setInteger("id",referencingObject.getId());

		        int rowCount = query.executeUpdate();

		        if (logger.isDebugEnabled()){logger.debug("Rows affected: " + rowCount);}

		        session.refresh(referencingObject);

		        if (refHolder.otherClass == IntextReference.class){

		            IntextReference intextRef = CdmBase.deproxy(referencingObject, IntextReference.class);

		            IIntextReferencable refEnt = intextRef.getReferencedEntity();

		            if (refEnt != null) {

                        String newText = refEnt.getText() == null? null: refEnt.getText().replace(cdmBase2.getUuid().toString(), cdmBase1.getUuid().toString());

                        refEnt.setText(newText);

                        session.saveOrUpdate(refEnt);

                    }

		            //TODO

		            /*

		             * UPDATE LanguageString

		             * SET text = Replace(text, cdmBase2.getUuuid(), cdmBase1.getUuid)

		             * WHERE id IN (SELECT * FROM IntextReference

		             *

		             */

		            System.out.println("IntextReference found");

		        }

	        }

	    }

		session.flush();

	}

	private Field getFieldRecursive(Class<?> clazz, String propertyName) throws NoSuchFieldException{

		try {

			return clazz.getDeclaredField(propertyName);

		} catch (NoSuchFieldException e) {

			Class<?> superClass = clazz.getSuperclass();

			if (CdmBase.class.isAssignableFrom(superClass)){

				return getFieldRecursive(superClass, propertyName);

			}else{

				throw e;

			}

		}

	}

	/**

	 * @throws NoSuchFieldException

	 * @throws SecurityException

	 * @throws IllegalAccessException

	 * @throws IllegalArgumentException

	 *

	 */

	private void reallocateSingleItem_Old(CdmBase cdmBase1, CdmBase cdmBase2, ReferenceHolder refHolder) throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {

		List<CdmBase> referencingObjects = genericDao.getCdmBasesByFieldAndClass(refHolder.otherClass, refHolder.propertyName, cdmBase2, null);

		for (CdmBase referencingObject : referencingObjects){

			Field referencingField = refHolder.otherClass.getDeclaredField(refHolder.propertyName);

			referencingField.setAccessible(true);

			Object test = referencingField.get(referencingObject);

			assert(test.equals(cdmBase2));

			referencingField.set(referencingObject, cdmBase1);

		}

	}

	/**

	 * @param <T>

	 * @param clazz

	 * @param sessionFactory

	 */

	private <T> Set<String> getCollectionRoles(Class<T> clazz,

			SessionFactoryImpl sessionFactory) {

		Set<String> collectionRoles = null;

		ClassMetadata classMetaData = sessionFactory.getClassMetadata(clazz);

		if (classMetaData instanceof AbstractEntityPersister){

			AbstractEntityPersister persister = (AbstractEntityPersister)classMetaData;

			String rootName = persister.getRootEntityName();

			collectionRoles = sessionFactory.getCollectionRolesByEntityParticipant(rootName);

			for (String collectionRole : collectionRoles){

				CollectionMetadata collMetadata = sessionFactory.getCollectionMetadata(collectionRole);

				CollectionPersister collPersister = sessionFactory.getCollectionPersister(collectionRole);

				logger.debug("");

			}

		}else{

			logger.warn("Class metadata is not of type AbstractEntityPersister");

			throw new UnhandledException("Class metadata is not of type AbstractEntityPersister", null);

		}

		return collectionRoles;

	}

	private <T extends CdmBase> void makeMergeProperty(T cdmBase1, T cdmBase2, Type propertyType, String propertyName, SessionFactoryImpl sessionFactory, boolean isCollection) throws MergeException{

		try {

			Class<T> clazz = (Class<T>)cdmBase1.getClass();

			if (CdmGenericDaoImpl.isNoDoType(propertyType)){

						//do nothing

			}else if (propertyType.isEntityType()){

				//Field field = clazz.getField(propertyName);

				EntityType entityType = (EntityType)propertyType;

				String associatedEntityName = entityType.getAssociatedEntityName();

				Class<?> entityClass = Class.forName(associatedEntityName);

//				 Type refPropType = sessionFactory.getReferencedPropertyType(entityClass.getCanonicalName(), propertyName);

				Set<String> collectionRoles = getCollectionRoles(clazz, sessionFactory);

				for (String collectionRole : collectionRoles){

					CollectionMetadata collMetadata = sessionFactory.getCollectionMetadata(collectionRole);

					String role = collMetadata.getRole();

					logger.debug(role);

				}

//				if (entityClass.isInterface()){

//					logger.debug("So ein interface");

//				}

//				if (entityClass.isAssignableFrom(clazz)){

//					makeSingleProperty(referencedClass, entityClass, propertyName, cdmClass, result, isCollection);

//				}

			}else if (propertyType.isCollectionType()){

				CollectionType collectionType = (CollectionType)propertyType;

				String role = collectionType.getRole();

				Type elType = collectionType.getElementType(sessionFactory);

				String n = collectionType.getAssociatedEntityName(sessionFactory);

				CollectionMetadata collMetadata = sessionFactory.getCollectionMetadata(role);

				if (collMetadata instanceof OneToManyPersister){

					OneToManyPersister oneManyPersister = (OneToManyPersister)collMetadata;

					String className = oneManyPersister.getOwnerEntityName();

					Class<?> myClass = Class.forName(className);

					Field field = myClass.getDeclaredField(propertyName);

					field.setAccessible(true);

					try {

						if (collectionType instanceof SetType){

							Set<?> set2 = (Set<?>)field.get(cdmBase2);

							Set<Object> set1 = (Set<Object>)field.get(cdmBase1);

							for (Object obj2: set2){

								set1.add(obj2);

							}

						}

					} catch (IllegalArgumentException e) {

						// TODO Auto-generated catch block

						e.printStackTrace();

					} catch (IllegalAccessException e) {

						// TODO Auto-generated catch block

						e.printStackTrace();

					}

				}

				logger.debug("");

//			makePropertyType(result, referencedClass, sessionFactory, cdmClass, elType, propertyName, true);

			}else if (propertyType.isAnyType()){

				AnyType anyType = (AnyType)propertyType;

				Field field = clazz.getDeclaredField(propertyName);

				Class returnType = field.getType();

//			if (returnType.isInterface()){

//				logger.debug("So ein interface");

//			}

//			if (returnType.isAssignableFrom(referencedClass)){

//				makeSingleProperty(referencedClass, returnType, propertyName, cdmClass, result, isCollection);

//			}

			}else if (propertyType.isComponentType()){

				ComponentType componentType = (ComponentType)propertyType;

				Type[] subTypes = componentType.getSubtypes();

//		Field field = cdmClass.getDeclaredField(propertyName);

//		Class returnType = field.getType();

				int propertyNr = 0;

				for (Type subType: subTypes){

					String subPropertyName = componentType.getPropertyNames()[propertyNr];

					if (! CdmGenericDaoImpl.isNoDoType(subType)){

						logger.warn("SubType not yet handled: " + subType);

					}

//					handlePropertyType(referencedCdmBase, result, referencedClass,

//					sessionFactory, cdmClass, subType, subPropertyName, isCollection);

					propertyNr++;

				}

			}else{

				logger.warn("propertyType not yet handled: " + propertyType.getName());

			}

			//OLD:

					//		if (! type.isInterface()){

			//		if (referencedClass.isAssignableFrom(type)||

			//				type.isAssignableFrom(referencedClass) && CdmBase.class.isAssignableFrom(type)){

			//			handleSingleClass(referencedClass, type, field, cdmClass, result, referencedCdmBase, false);

			//		}

			//	//interface

			//	}else if (type.isAssignableFrom(referencedClass)){

			//			handleSingleClass(referencedClass, type, field, cdmClass, result, referencedCdmBase, false);

		} catch (Exception e) {

			throw new MergeException(e);

		}

	}

}