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1   //----------------------------------------------------------------------
2   // 
3   // PerfectJPattern: "Design patterns are good but components are better!" 
4   // HibernateGenericDao.java Copyright (c) 2009 Giovanni Azua Garcia
5   // bravegag@hotmail.com
6   //  
7   // This program is free software; you can redistribute it and/or
8   // modify it under the terms of the GNU General Public License
9   // as published by the Free Software Foundation; either version 3
10  // of the License, or (at your option) any later version.
11  //
12  // This program is distributed in the hope that it will be useful,
13  // but WITHOUT ANY WARRANTY; without even the implied warranty of
14  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  // GNU General Public License for more details.
16  //
17  // You should have received a copy of the GNU General Public License
18  // along with this program; if not, see <http://www.gnu.org/licenses/>.
19  //
20  //----------------------------------------------------------------------
21  package org.perfectjpattern.jee.integration.dao;
22  
23  import java.io.*;
24  import java.util.*;
25  
26  import javax.persistence.*;
27  
28  import org.apache.commons.lang.*;
29  import org.hibernate.*;
30  import org.hibernate.criterion.*;
31  import org.perfectjpattern.jee.api.integration.dao.*;
32  
33  /**
34   * Hibernate-based implementation of {@link IGenericReadOnlyDao}
35   * 
36   * @param <Id> Identification type
37   * @param <Element> Element type
38   * 
39   * @author <a href="mailto:bravegag@hotmail.com">Giovanni Azua</a>
40   * @version $Revision: 1.0 $ $Date: Nov 26, 2007 9:15:14 PM $
41   */
42  @SuppressWarnings("hiding")
43  public 
44  class HibernateGenericDao<Id extends Serializable, Element>
45  extends JpaBaseDao<Id, Element>
46  implements IGenericDao<Id, Element>
47  {
48      //------------------------------------------------------------------------
49      // public    
50      //------------------------------------------------------------------------
51      /** 
52       * {@inheritDoc}
53       */
54      @SuppressWarnings("unchecked")
55      public List<Element>
56      findByExample(Element anElement, String ... anExcludeProperties)
57      throws DaoException, IllegalArgumentException
58      {
59          Validate.notNull(anElement, "'anElement' must not be null");        
60          Validate.notNull(anExcludeProperties, 
61              "'anExcludeProperties' must not be null");
62          
63          List<Element> myElements = null;
64          
65          try
66          {
67              Session mySession = getActualSession();            
68              
69              Criteria myCriteria = mySession.createCriteria(
70                  getPersistentClass());
71              Example myExample = Example.create(anElement);
72              for (String myPropertyName : anExcludeProperties)
73              {
74                  myExample.excludeProperty(myPropertyName);
75              }
76              
77              myElements = myCriteria.add(myExample).list();
78              
79              return myElements;            
80          }
81          catch (HibernateException anException) 
82          {
83              throw new DaoException(anException);
84          }        
85      }
86      
87      //------------------------------------------------------------------------
88      // protected    
89      //------------------------------------------------------------------------
90      /**
91       * Constructs a {@link HibernateGenericDao} instance from the 
92       * persistent class type, the {@link ISessionStrategy} that creates 
93       * {@link Session} instances and the {@link ITransactionStrategy} that 
94       * creates {@link Transaction} instances 
95       * 
96       * @param aPersistentClass The persistent Java Bean class
97       * @param aSessionStrategy Factory that creates Sessions
98       * @param aTransactionStrategy Factory that creates Transaction
99       */
100     protected
101     HibernateGenericDao(Class<Element> aPersistentClass, 
102         ISessionStrategy aSessionStrategy, 
103             ITransactionStrategy aTransactionStrategy)
104     throws IllegalArgumentException
105     {
106         super(aPersistentClass, aSessionStrategy, aTransactionStrategy);
107     }
108 
109     //------------------------------------------------------------------------
110     /**
111      * Returns the Session
112      * 
113      * @return the Session
114      */
115     protected Session
116     getActualSession()
117     throws DaoException    
118     {
119         Object mySession = getSession().getDelegate();
120         while (mySession != null && mySession instanceof EntityManager)
121         {
122             mySession = ((EntityManager) mySession).getDelegate();
123         }
124         
125         assert mySession instanceof Session : 
126             "Actual Session must be a Hibernate Session";
127         
128         return (Session) mySession;
129     }                
130 }