EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.model.common;

import java.util.HashSet;

import java.util.Set;

import javax.persistence.MappedSuperclass;

import javax.persistence.Transient;

import javax.xml.bind.annotation.XmlAccessType;

import javax.xml.bind.annotation.XmlAccessorType;

import javax.xml.bind.annotation.XmlAttribute;

import javax.xml.bind.annotation.XmlEnum;

import javax.xml.bind.annotation.XmlEnumValue;

import javax.xml.bind.annotation.XmlRootElement;

import javax.xml.bind.annotation.XmlTransient;

import javax.xml.bind.annotation.XmlType;

import org.apache.log4j.Logger;

import eu.etaxonomy.cdm.model.reference.ReferenceBase;

/**

 * @author m.doering

 */

@XmlAccessorType(XmlAccessType.FIELD)

@XmlType(name = "RelationshipBase")

@XmlRootElement(name = "RelationshipBase")

@MappedSuperclass

public abstract class RelationshipBase<FROM extends IRelated, TO extends IRelated, TYPE extends RelationshipTermBase> extends ReferencedEntityBase {

	private static final long serialVersionUID = -5030154633820061997L;

	@SuppressWarnings("unused")

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

	@XmlAttribute(name = "isDoubtful")

	private boolean doubtful;

	//this set is used only for persistence (CdmDeleteListener) to delete savely relationships and update there former related objects

	@XmlTransient

	@Transient

	protected Set<IRelated> deletedObjects = new HashSet<IRelated>();

	/**

	 * enumeration and String representation of the <code>relatedFrom</code> and

	 * <code>relatedTo</code> bean propertys. Intended to be used in the

	 * persistence layer only.

	 */

	@XmlEnum

	public enum Direction {

		@XmlEnumValue("relatedFrom")

		relatedFrom, 

		@XmlEnumValue("relatedTo")

		relatedTo

	}

	protected RelationshipBase(){

		super();

	}

	/**

	 * Creates a relationship between 2 objects and adds it to the respective

	 * relation sets of both objects.

	 * 

	 * @param from

	 * @param to

	 * @param type

	 * @param citation

	 * @param citationMicroReference

	 */

	protected RelationshipBase(FROM from, TO to, TYPE type, ReferenceBase citation, String citationMicroReference) {

		super(citation, citationMicroReference, null);

		setRelatedFrom(from);

		setRelatedTo(to);

		setType(type);

		from.addRelationship(this);

		to.addRelationship(this);

	}

	public abstract TYPE getType();

	public abstract void setType(TYPE type);

	protected abstract FROM getRelatedFrom();

	protected abstract void setRelatedFrom(FROM relatedFrom);

	protected abstract TO getRelatedTo();

	protected abstract void setRelatedTo(TO relatedTo);

	/**

	 * A boolean flag that marks the relationship between two objects as doubtful

	 * Please be aware that this flag should not be used to mark any status of the 

	 * objects themselfs. E.g. when marking a synonym relationship as doubtful

	 * this means that it is doubtful that the synonym is really a synonym to the

	 * taxon. It does not mean that the synonym is doubtfully a synonym.

	 * @return true, if the relationship is doubtful, false otherwise

	 */

	public boolean isDoubtful(){

		return this.doubtful;

	}

	public void setDoubtful(boolean doubtful){

		this.doubtful = doubtful;

	}

	public boolean isRemoved(){

		if ( this.getRelatedFrom() == null ^ this.getRelatedTo() == null){

			throw new IllegalStateException("A relationship may have only both related object as null or none. But just one is null!");

		}

		return this.getRelatedFrom() == null || this.getRelatedTo() == null;

	}

	public Set getDeletedObjects(){

		return this.deletedObjects;

	}

// TODO

//	UUID toUuid; 

//	UUID fromUuid;

//	

//	@Transient

//	public UUID getToUuidCache(){

//		return relationTo.getUuid();

//	}

//	protected void setToUuid(UUID uuid){

//		toUuid = uuid;

//	}

//	

//	public UUID getFromUuid(){

//		return relationTo.getUuid();

//	}

//	protected void setFromUuid(UUID uuid){

//		fromUuid = uuid;

//	}

}