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.UUID;

import javax.persistence.Basic;

import javax.persistence.FetchType;

import javax.persistence.ManyToOne;

import javax.persistence.MappedSuperclass;

import javax.xml.bind.annotation.XmlAccessType;

import javax.xml.bind.annotation.XmlAccessorType;

import javax.xml.bind.annotation.XmlElement;

import javax.xml.bind.annotation.XmlIDREF;

import javax.xml.bind.annotation.XmlSchemaType;

import javax.xml.bind.annotation.XmlType;

import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;

import org.apache.log4j.Logger;

import org.hibernate.annotations.Type;

import org.hibernate.search.annotations.Field;

import org.hibernate.search.annotations.FieldBridge;

import org.joda.time.DateTime;

import eu.etaxonomy.cdm.common.CdmUtils;

import eu.etaxonomy.cdm.hibernate.DateTimeBridge;

import eu.etaxonomy.cdm.jaxb.DateTimeAdapter;

import eu.etaxonomy.cdm.strategy.match.Match;

import eu.etaxonomy.cdm.strategy.match.MatchMode;

/**

 * The class keeps track of versions via a full linked list to different version objects, or a simple updated/updatedBy property in the same object.

 * 

 * Full versioning allows concrete subclasses to keep track of previous or later versions of an object.

 * A different version is another (persistent) java object, but with the same UUID. 

 * The version history is established as a linked list of the version objects in time.

 * If versioning via the linked list is used, updated/updatedBy is the same as created/createdBy (better NULL?).

 * 

 * Versioning can be turned off and in this case this class provides updated/updatedBy to keep track of the latest change event.

 * 

 * @author m.doering

 * @created 08-Nov-2007 13:07:01

 *

 * @param <T>

 */

@XmlAccessorType(XmlAccessType.FIELD)

@XmlType(name = "VersionableEntity", propOrder = {

    "updated",

    "updatedBy"

})

@XmlJavaTypeAdapter(value=DateTimeAdapter.class,type=DateTime.class)

@MappedSuperclass

public abstract class VersionableEntity extends CdmBase implements IVersionableEntity{

	private static final long serialVersionUID = 1409299200302758513L;

	@SuppressWarnings("unused")

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

	@XmlElement(name ="Updated", type = String.class)

	@XmlJavaTypeAdapter(DateTimeAdapter.class)

	//@XmlElement(name ="Updated")

	//@XmlElement(name ="Updated")

	@Type(type="dateTimeUserType")

	@Basic(fetch = FetchType.LAZY)

	@Match(MatchMode.IGNORE)

	@Field(index = org.hibernate.search.annotations.Index.UN_TOKENIZED)

	@FieldBridge(impl = DateTimeBridge.class)

	private DateTime updated;

	@XmlElement(name = "UpdatedBy")

	@XmlIDREF

	@XmlSchemaType(name = "IDREF")

	@ManyToOne(fetch=FetchType.LAZY)

	@Match(MatchMode.IGNORE)

	private User updatedBy;

	public User getUpdatedBy(){

		return this.updatedBy;

	}

	/**

	 * 

	 * @param updatedBy    updatedBy

	 */

	public void setUpdatedBy(User updatedBy){

		this.updatedBy = updatedBy;

	}

	/**

	 * 

	 * @return

	 */

	public DateTime getUpdated(){

		return this.updated;

	}

	/**

	 * 

	 * @param updated    updated

	 */

	public void setUpdated(DateTime updated){

		this.updated = updated;

	}

	/**

	 * Is true if UUID and created timestamp are the same for the passed Object and this one.

	 * @see eu.etaxonomy.cdm.model.common.CdmBase#equals(java.lang.Object)

	 * See {@link http://www.hibernate.org/109.html hibernate109}, {@link http://www.geocities.com/technofundo/tech/java/equalhash.html geocities} 

	 * or {@link http://www.ibm.com/developerworks/java/library/j-jtp05273.html ibm}

	 * for more information about equals and hashcode. 

	 */

	@Override

	public boolean equals(Object obj) {

		if (obj == this){

			return true;

		}

		if (obj == null){

			return false;

		}

		if (!CdmBase.class.isAssignableFrom(obj.getClass())){

			return false;

		}

		ICdmBase cdmObj = (ICdmBase)obj;

		boolean uuidEqual;

		UUID objUuid = cdmObj.getUuid();

		if (objUuid == null){

			throw new NullPointerException("CdmBase is missing UUID");

		}

		uuidEqual = objUuid.equals(this.getUuid());

		//TODO is this still needed?

		boolean createdEqual = CdmUtils.nullSafeEqual(cdmObj.getCreated(), this.getCreated());

		if (! uuidEqual || !createdEqual){

				return false;

		}

		return true;

	}

//********************** CLONE *****************************************/

	/** 

	 * Clones this versionable entity.

	 * Set fields for nextVersion, previousVersion, updated, updatedBy and createdBy are set to <tt>null</tt>

	 * The id is set to 0.

	 * The uuid is created new.

	 * The createdWhen is set to the current date.

	 * @see java.lang.Object#clone()

	 */

	@Override

	public Object clone() throws CloneNotSupportedException{

		VersionableEntity result = (VersionableEntity)super.clone();

		result.setUpdated(null);

		result.setUpdatedBy(null);

		//no changes to: -

		return result;

	}

}