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1   /*
2    * Copyright (c) 2001, Zoltan Farkas All Rights Reserved.
3    *
4    * This library is free software; you can redistribute it and/or
5    * modify it under the terms of the GNU Lesser General Public
6    * License as published by the Free Software Foundation; either
7    * version 2.1 of the License, or (at your option) any later version.
8    *
9    * This library is distributed in the hope that it will be useful,
10   * but WITHOUT ANY WARRANTY; without even the implied warranty of
11   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12   * GNU General Public License for more details.
13   *
14   * You should have received a copy of the GNU Lesser General Public
15   * License along with this program; if not, write to the Free Software
16   * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17   */
18  package net.sf.zel.vm;
19  
20  import java.util.HashMap;
21  import java.util.Map;
22  import java.util.WeakHashMap;
23  import javax.annotation.concurrent.NotThreadSafe;
24  
25  /**
26   * simple implementation for resultcache.
27   * @author zoly
28   */
29  @NotThreadSafe
30  public class SimpleResultCache implements ResultCache
31  {
32  
33      private final Map permanentCache;
34  
35      private final Map transientCache;
36  
37      public SimpleResultCache()
38      {
39          permanentCache =  new HashMap();
40          transientCache = new WeakHashMap();
41      }
42  
43  
44  
45      @Override
46      public void putPermanentResult(Object key, Object result)
47      {
48          permanentCache.put(key, result);
49      }
50  
51      @Override
52      public void putTransientResult(Object key, Object result)
53      {
54          transientCache.put(key, result);
55      }
56  
57      @Override
58      public Object getResult(Object key)
59      {
60          Object result = permanentCache.get(key);
61          if (result == null)
62              result = transientCache.get(key);
63          return result;
64      }
65  
66  }