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1   /***
2    * @(#)DAOFactoryImpl.java
3    * 
4    * JFoxSOAF, Service-Oriented Application Framework
5    * 
6    * Copyright(c) JFoxSOAF Team
7    * 
8    * Licensed under the GNU LGPL, Version 2.1 (the "License"); 
9    * you may not use this file except in compliance with the License. 
10   * You may obtain a copy of the License at  
11   * 
12   * http://www.gnu.org/copyleft/lesser.html
13   * 
14   * Unless required by applicable law or agreed to in writing, software
15   * distributed under the License is distributed on an "AS IS" BASIS, 
16   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
17   * See the License for the specific language governing permissions and 
18   * limitations under the License. 
19   * 
20   * For more information, please visit:
21   * http://www.jfox.cn/confluence/display/JFoxSOAF/Home
22   * http://www.huihoo.org/jfox/jfoxsoaf
23   */
24  
25  package org.huihoo.jfox.soaf.services.dao;
26  
27  import java.util.Collections;
28  import java.util.HashMap;
29  import java.util.Map;
30  
31  import org.huihoo.jfox.soaf.exception.DAOException;
32  
33  /***
34   * <p>
35   * Alternatvie DAO Factory implementation with reflection.
36   * </p>
37   * 
38   * @author <a href="mailto:founder_chen@yahoo.com.cn">Peter Cheng </a>
39   * @version $Revision: 1.1 $ $Date: 2005/04/27 08:02:53 $
40   * @version Revision: 1.0
41   */
42  
43  public class DAOFactoryImpl implements DAOFactory {
44  
45      private Map daoCache = Collections.synchronizedMap(new HashMap());
46  
47      /***
48       * This method instantiates the DAO class.
49       * 
50       * @param clazz
51       * @throws DAOException
52       */
53      public DAO getDAO(Class clazz) throws DAOException {
54  
55          try {
56              if (daoCache.containsKey(clazz.getName())) {
57                  return (DAO) daoCache.get(clazz.getName());
58              } else {
59                  Object obj = Class.forName(clazz.getName()).newInstance();
60                  daoCache.put(clazz.getName(), obj);
61                  return (DAO) obj;
62              }
63          } catch (InstantiationException e) {
64              throw new DAOException("DAOFactoryImpl.getDAO(" + clazz.getName()
65                      + "):  NamingException while getting DAO type : \n"
66                      + e.getMessage());
67          } catch (IllegalAccessException e) {
68              throw new DAOException("DAOFactoryImpl.getDAO(" + clazz.getName()
69                      + "):  NamingException while getting DAO type : \n"
70                      + e.getMessage());
71          } catch (ClassNotFoundException e) {
72              throw new DAOException("DAOFactoryImpl.getDAO(" + clazz.getName()
73                      + "):  NamingException while getting DAO type : \n"
74                      + e.getMessage());
75          }
76      }
77  
78  }