cdmlib-persistence/src/main/java/eu/etaxonomy/cdm/persistence/hibernate/PostMergeEntityListener.java

   1 // $Id$
   2 /**
   3  * Copyright (C) 2015 EDIT
   4  * European Distributed Institute of Taxonomy
   5  * http://www.e-taxonomy.eu
   6  *
   7  * The contents of this file are subject to the Mozilla Public License Version 1.1
   8  * See LICENSE.TXT at the top of this package for the full license terms.
   9  */
  10 package eu.etaxonomy.cdm.persistence.hibernate;
  11
  12 import java.util.Map;
  13
  14 import org.hibernate.Hibernate;
  15 import org.hibernate.HibernateException;
  16 import org.hibernate.event.spi.MergeEvent;
  17 import org.hibernate.event.spi.MergeEventListener;
  18
  19 import eu.etaxonomy.cdm.model.common.CdmBase;
  20
  21 /**
  22  * @author cmathew
  23  * @date 23 Sep 2015
  24  *
  25  */
  26 public class PostMergeEntityListener implements MergeEventListener {
  27
  28     private static final long serialVersionUID = 1565797119368313987L;
  29
  30     @Override
  31     public void onMerge(MergeEvent event) throws HibernateException {
  32
  33     }
  34
  35     @Override
  36     public void onMerge(MergeEvent event, Map copiedAlready) throws HibernateException {
  37         // at this point the original entity to merge has already been copied to the result
  38         // => the result is an exact copy of the original EXCEPT or the the id which is set by hibernate
  39         // the following code sets the id in the original entity so that it can be used as a return value
  40         // for the CdmEntityDaoBase.merge(T transientObject, boolean returnTransientEntity) call
  41         if(event.getOriginal() != null && CdmBase.class.isAssignableFrom(event.getOriginal().getClass()) &&
  42                 event.getResult() != null && CdmBase.class.isAssignableFrom(event.getResult().getClass())) {
  43             CdmBase original = (CdmBase) event.getOriginal();
  44             CdmBase result = (CdmBase) event.getResult();
  45             if(original != null && Hibernate.isInitialized(original) && original.getId() == 0 &&
  46                     result != null && Hibernate.isInitialized(result)) {
  47                 original.setId(result.getId());
  48
  49             }
  50         }
  51     }
  52
  53 }