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1   /*
2    * Copyright (c) 2003 Peter Antman, Teknik i Media  <peter.antman@tim.se>
3    *
4    * $Id: FileCachedStream.java,v 1.1.1.1 2004/05/19 12:07:30 pra Exp $
5    *
6    * This library is free software; you can redistribute it and/or
7    * modify it under the terms of the GNU Lesser General Public
8    * License as published by the Free Software Foundation; either
9    * version 2 of the License, or (at your option) any later version
10   * 
11   * This library is distributed in the hope that it will be useful,
12   * but WITHOUT ANY WARRANTY; without even the implied warranty of
13   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   * Lesser General Public License for more details.
15   * 
16   * You should have received a copy of the GNU Lesser General Public
17   * License along with this library; if not, write to the Free Software
18   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19   */
20  package org.backsource.utils.io;
21  import java.io.File;
22  import java.io.IOException;
23  /***
24   * A StreamCache that cached data in temporary files.
25   *
26   * @author <a href="mailto:pra@tim.se">Peter Antman</a>
27   * @version $Revision: 1.1.1.1 $
28   */
29  
30  public class FileCachedStream extends ByteCachedStream{
31     protected static final String TMP_PREFIX ="FileCached";
32     protected static final String TMP_SUFIX =".tmp";
33     
34     public FileCachedStream (){
35        
36  
37     }
38     /***
39      * Get a CachedOutputStream.
40      *
41      * <p>The typical usecase for this is to later use it to get
42      * a CachedInputStream from it.
43      */
44     public CachedOutputStream getOutputStream() throws IOException {
45        File f = File.createTempFile(TMP_PREFIX,TMP_SUFIX);
46        f.deleteOnExit();
47        return new FileCachedOutputStream(f);
48     }
49  
50     /***
51      * Get a rewindable input stream from the given CachedOutputStream.
52      */
53     public CachedInputStream getInputStream(CachedOutputStream cout)throws IOException {
54        if ( cout instanceof FileCachedOutputStream ) {
55           return new FileCachedInputStream((FileCachedOutputStream)cout);
56        } // end of if ()
57        throw new IOException("The CachedOutputStream is not retrieved through this cache; it is not a FileCachedOutputStream");
58     }
59  
60  }// FileCachedStream