/*
    * EL4J, the Extension Library for the J2EE, adds incremental enhancements to
    * the spring framework, http://el4j.sf.net
    * Copyright (C) 2005 by ELCA Informatique SA, Av. de la Harpe 22-24,
    * 1000 Lausanne, Switzerland, http://www.elca.ch
    *
    * EL4J is published under the GNU Lesser General Public License (LGPL)
    * Version 2.1. See http://www.gnu.org/licenses/
    *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
   * GNU Lesser General Public License for more details.
   *
   * For alternative licensing, please contact info@elca.ch
   */
  
  package ch.elca.el4j.services.persistence.generic.dto;
  
  import javax.persistence.Column;
  import javax.persistence.Id;
  import javax.persistence.MappedSuperclass;
  import javax.persistence.Transient;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import ch.elca.el4j.util.codingsupport.ObjectUtils;
  
  /**
   * This class is an abstract dto which uses a string as key value and an integer
   * for optimistic locking version controlling.
   *
   * @svnLink $Revision: 3873 $;$Date: 2009-08-04 13:59:45 +0200 (Di, 04. Aug 2009) $;$Author: swismer $;$URL: https://el4j.svn.sourceforge.net/svnroot/el4j/branches/el4j_3_1/el4j/framework/modules/core/src/main/java/ch/elca/el4j/services/persistence/generic/dto/AbstractStringKeyIntOptimisticLockingDto.java $
   *
   * @author Martin Zeltner (MZE)
   */
  @MappedSuperclass
  public abstract class AbstractStringKeyIntOptimisticLockingDto
  	extends AbstractIntOptimisticLockingDto
  	implements PrimaryKeyOptimisticLockingObject {
  	
  	/**
  	 * The logger.
  	 */
  	private static Logger s_logger = LoggerFactory.getLogger(AbstractStringKeyIntOptimisticLockingDto.class);
  	
  	/**
  	 * Primary key.
  	 */
  	private String m_key;
  	
  	/**
  	 * Has the hashCode value been leaked while being in transient state?
  	 */
  	private boolean m_transientHashCodeLeaked = false;
  
  	/**
  	 * {@inheritDoc}
  	 */
  	@Transient
  	public boolean isKeyNew() {
  		return m_key == null;
  	}
  
  	/**
  	 * @return Returns the key.
  	 */
  	@Id
  	@Column(name = "KEYID")
  	public String getKey() {
  		return m_key;
  	}
  	
  	/**
  	 * {@inheritDoc}
  	 */
  	@Transient
  	public Object getKeyAsObject() {
  		return isKeyNew() ? null : getKey();
  	}
  
  	/**
  	 * @param key The key to set.
  	 */
  	public void setKey(String key) {
  		m_key = key;
  	}
  
  	/**
  	 * {@inheritDoc}
  	 */
  	public void setKey(Object keyObject) {
  		String key = (keyObject == null) ? null : keyObject.toString();
  		setKey(key);
  	}
  
  	/**
  	 * {@inheritDoc}
 	 */
 	public int hashCode() {
 		if (m_key == null) {
 			m_transientHashCodeLeaked = true;
 			return super.hashCode();
 		} else {
 			if (m_transientHashCodeLeaked) {
 				s_logger.error("hashCode() has be called once on transient state and once on persistent state  "
 					+ "of object '" + this.toString() + "' (" + getClass().toString() + "). "
 					+ "This can happen if you insert a transient object into a collection and persist them afterwards. "
 					+ "Save the objects before you insert them into a collection!");
 			}
 			return m_key.hashCode();
 		}
 	}
 
 	/**
 	 * {@inheritDoc}
 	 */
 	public boolean equals(Object obj) {
 		if (this == obj) {
 			return true;
 		}
 		if (obj instanceof AbstractStringKeyIntOptimisticLockingDto) {
 			AbstractStringKeyIntOptimisticLockingDto other
 				= (AbstractStringKeyIntOptimisticLockingDto) obj;
 			return ObjectUtils.nullSaveEquals(m_key, other.m_key);
 		} else {
 			return false;
 		}
 	}
 }