root/trunk/cdmlib/cdmlib-model/src/main/java/eu/etaxonomy/cdm/model/common/CdmBase.java

/**
* 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.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.UUID;

import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.MappedSuperclass;
import javax.persistence.Transient;
import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlID;
import javax.xml.bind.annotation.XmlIDREF;
import javax.xml.bind.annotation.XmlSchemaType;
import javax.xml.bind.annotation.XmlTransient;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;

import org.apache.log4j.Logger;
import org.hibernate.annotations.GenericGenerator;
import org.hibernate.annotations.NaturalId;
import org.hibernate.annotations.Type;
import org.hibernate.search.annotations.DocumentId;
import org.hibernate.search.annotations.Field;
import org.hibernate.search.annotations.FieldBridge;
import org.joda.time.DateTime;

import eu.etaxonomy.cdm.hibernate.DateTimeBridge;
import eu.etaxonomy.cdm.hibernate.HibernateProxyHelper;
import eu.etaxonomy.cdm.jaxb.DateTimeAdapter;
import eu.etaxonomy.cdm.jaxb.UUIDAdapter;
import eu.etaxonomy.cdm.strategy.match.Match;
import eu.etaxonomy.cdm.strategy.match.MatchMode;




/**
 * The base class for all CDM domain classes implementing UUIDs and bean property change event firing.
 * It provides a globally unique UUID and keeps track of creation date and person.
 * The UUID is the same for different versions (see {@link VersionableEntity}) of a CDM object, so a locally unique id exists in addition
 * that allows to safely access and store several objects (=version) with the same UUID.
 *
 * This class together with the {@link eu.etaxonomy.cdm.aspectj.PropertyChangeAspect}
 * will fire bean change events to all registered listeners. Listener registration and event firing
 * is done with the help of the {@link PropertyChangeSupport} class.
 *
 * @author m.doering
 *
 */
@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "CdmBase", propOrder = {
    "created",
    "createdBy"
})
@MappedSuperclass
public abstract class CdmBase implements Serializable, ICdmBase, Cloneable{
        private static final long serialVersionUID = -3053225700018294809L;
        @SuppressWarnings("unused")
        private static final Logger logger = Logger.getLogger(CdmBase.class);

        @Transient
        @XmlTransient
        private PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);

        //@XmlAttribute(name = "id", required = true)
        @XmlTransient
        @Id
//      @GeneratedValue(generator = "system-increment")
//      @GeneratedValue(generator = "enhanced-table")
        @GeneratedValue(generator = "custom-enhanced-table")
        @DocumentId
        @Match(MatchMode.IGNORE)
        @NotNull
        @Min(0)
        private int id;

        @XmlAttribute(required = true)
    @XmlJavaTypeAdapter(UUIDAdapter.class)
    @Type(type="uuidUserType")
        @NaturalId // This has the effect of placing a "unique" constraint on the database column
        @XmlID
        @Column(length=36)
        @Match(MatchMode.IGNORE)
        @NotNull
        protected UUID uuid;

        @XmlElement (name = "Created", type= String.class)
        @XmlJavaTypeAdapter(DateTimeAdapter.class)
        @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 created;

        @XmlElement (name = "CreatedBy")
        @XmlIDREF
        @XmlSchemaType(name = "IDREF")
        @ManyToOne(fetch=FetchType.LAZY)
    @Match(MatchMode.IGNORE)
        private User createdBy;

        /**
         * Class constructor assigning a unique UUID and creation date.
         * UUID can be changed later via setUuid method.
         */
        public CdmBase() {
                this.uuid = UUID.randomUUID();
                this.created = new DateTime().withMillisOfSecond(0);
        }

        /**
         * see {@link PropertyChangeSupport#addPropertyChangeListener(PropertyChangeListener)}
         * @param listener
         */
        public void addPropertyChangeListener(PropertyChangeListener listener) {
                propertyChangeSupport.addPropertyChangeListener(listener);
        }

        /**
         * see {@link PropertyChangeSupport#addPropertyChangeListener(String, PropertyChangeListener)}
         */
        public void addPropertyChangeListener(String propertyName, PropertyChangeListener listener) {
                propertyChangeSupport.addPropertyChangeListener(propertyName, listener);
        }

        /**
         * see {@link PropertyChangeSupport#addPropertyChangeListener(PropertyChangeListener)}
         */
        public void removePropertyChangeListener(PropertyChangeListener listener) {
                propertyChangeSupport.removePropertyChangeListener(listener);
        }

        /**
         * @see PropertyChangeSupport#addPropertyChangeListener(String, PropertyChangeListener)
         */
        public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) {
                propertyChangeSupport.removePropertyChangeListener(propertyName, listener);
        }

        public boolean hasListeners(String propertyName) {
                return propertyChangeSupport.hasListeners(propertyName);
        }

        public void firePropertyChange(String property, String oldval, String newval) {
                propertyChangeSupport.firePropertyChange(property, oldval, newval);
        }
        public void firePropertyChange(String property, int oldval, int newval) {
                propertyChangeSupport.firePropertyChange(property, oldval, newval);
        }
        public void firePropertyChange(String property, float oldval, float newval) {
                propertyChangeSupport.firePropertyChange(property, oldval, newval);
        }
        public void firePropertyChange(String property, boolean oldval, boolean newval) {
                propertyChangeSupport.firePropertyChange(property, oldval, newval);
        }
        public void firePropertyChange(String property, Object oldval, Object newval) {
                propertyChangeSupport.firePropertyChange(property, oldval, newval);
        }
        public void firePropertyChange(PropertyChangeEvent evt) {
                propertyChangeSupport.firePropertyChange(evt);
        }

        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#getUuid()
         */
        public UUID getUuid() {
                return uuid;
        }
        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#setUuid(java.util.UUID)
         */
        public void setUuid(UUID uuid) {
                this.uuid = uuid;
        }

        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#getId()
         */
        public int getId() {
                return this.id;
        }
        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#setId(int)
         */
        public void setId(int id) {
                this.id = id;
        }

        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#getCreated()
         */
        public DateTime getCreated() {
                return created;
        }
        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#setCreated(java.util.Calendar)
         */
        public void setCreated(DateTime created) {
                if (created != null){
                        new DateTime();
                        created = created.withMillisOfSecond(0);
                        //created.set(Calendar.MILLISECOND, 0);  //old, can be deleted
                }
                this.created = created;
        }


        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#getCreatedBy()
         */
        public User getCreatedBy() {
                return this.createdBy;
        }
        /* (non-Javadoc)
         * @see eu.etaxonomy.cdm.model.common.ICdmBase#setCreatedBy(eu.etaxonomy.cdm.model.agent.Person)
         */
        public void setCreatedBy(User createdBy) {
                this.createdBy = createdBy;
        }

// ************************** Hibernate proxies *******************/
        /**
         * These methods are present due to HHH-1517 - that in a one-to-many
         * relationship with a superclass at the "one" end, the proxy created
         * by hibernate is the superclass, and not the subclass, resulting in
         * a classcastexception when you try to cast it.
         *
         * Hopefully this will be resolved through improvements with the creation of
         * proxy objects by hibernate and the following methods will become redundant,
         * but for the time being . . .
         * @param <T>
         * @param object
         * @param clazz
         * @return
         * @throws ClassCastException
         */
        //non-static does not work because javassist already unwrapps the proxy before calling the method
         public static <T extends CdmBase> T deproxy(Object object, Class<T> clazz) throws ClassCastException {
                 return HibernateProxyHelper.deproxy(object, clazz);
         }

         public boolean isInstanceOf(Class<? extends CdmBase> clazz) throws ClassCastException {
             return HibernateProxyHelper.isInstanceOf(this, clazz);
         }

// ************* Object overrides *************************/

        /**
         * Is true if UUID is the same for the passed Object and this one.
         * @see java.lang.Object#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 = cdmObj.getUuid().equals(this.getUuid());
                boolean createdEqual = cdmObj.getCreated().equals(this.getCreated());
                if (! uuidEqual || !createdEqual){
                                return false;
                }
                return true;
        }


        /** Overrides {@link java.lang.Object#hashCode()}
         *  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 int hashCode() {
                   int hashCode = 7;
                   if(this.getUuid() != null) {
                           //this unfortunately leads to errors when loading maps via hibernate
                           //as hibernate computes hash values for CdmBase objects used as key at
                           // a time when the uuid is not yet loaded from the database. Therefore
                           //the hash values later change and give wrong results when retrieving
                           //data from the map (map.get(key) returns null, though there is an entry
                           //for key in the map.
                           //see further comments in #2114
                       int result = 29 * hashCode + this.getUuid().hashCode();
//                     int shresult = 29 * hashCode + Integer.valueOf(this.getId()).hashCode();
                           return result;
                   } else {
                           return 29 * hashCode;
                   }
        }

        /**
         * Overrides {@link java.lang.Object#toString()}.
         * This returns an String that identifies the object well without beeing necessarily unique.
         * Specification: This method should never call other object' methods so it can be well used for debugging
         * without problems like lazy loading, unreal states etc.
         * Note: If overriding this method's javadoc always copy or link the above requirement.
         * If not overwritten by a subclass method returns the class, id and uuid as a string for any CDM object.
         * For example: Taxon#13<b5938a98-c1de-4dda-b040-d5cc5bfb3bc0>
         * @see java.lang.Object#toString()
         */
        @Override
        public String toString() {
                return this.getClass().getSimpleName()+"#"+this.getId()+"<"+this.getUuid()+">";
        }

// **************** invoke methods **************************/

        protected void invokeSetMethod(Method method, Object object){
                try {
                        method.invoke(object, this);
                } catch (Exception e) {
                        e.printStackTrace();
                        //TODO handle exceptioin;
                }
        }

        protected void invokeSetMethodWithNull(Method method, Object object){
                try {
                        Object[] nul = new Object[]{null};
                        method.invoke(object, nul);
                } catch (Exception e) {
                        e.printStackTrace();
                        //TODO handle exceptioin;
                }
        }

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

        protected void clone(CdmBase clone){
                clone.setCreatedBy(createdBy);
                clone.setId(id);
                clone.propertyChangeSupport=new PropertyChangeSupport(clone);
                //Constructor Attributes
                //clone.setCreated(created);
                //clone.setUuid(getUuid());

        }

        /* (non-Javadoc)
         * @see java.lang.Object#clone()
         */
        @Override
        public Object clone() throws CloneNotSupportedException{
                CdmBase result = (CdmBase)super.clone();
                result.propertyChangeSupport=new PropertyChangeSupport(result);

                //TODO ?
                result.setId(0);
                result.setUuid(UUID.randomUUID());
                result.setCreated(new DateTime());
                result.setCreatedBy(null);

                //no changes to: -
                return result;
        }

}