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1   /*
2    * $Source: /usr/cvsroot/melati/melati/src/main/java/org/melati/util/MelatiWriter.java,v $
3    * $Revision: 1.20 $
4    *
5    * Copyright (C) 2000 Tim Joyce
6    *
7    * Part of Melati (http://melati.org), a framework for the rapid
8    * development of clean, maintainable web applications.
9    *
10   * Melati is free software; Permission is granted to copy, distribute
11   * and/or modify this software under the terms either:
12   *
13   * a) the GNU General Public License as published by the Free Software
14   *    Foundation; either version 2 of the License, or (at your option)
15   *    any later version,
16   *
17   *    or
18   *
19   * b) any version of the Melati Software License, as published
20   *    at http://melati.org
21   *
22   * You should have received a copy of the GNU General Public License and
23   * the Melati Software License along with this program;
24   * if not, write to the Free Software Foundation, Inc.,
25   * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the
26   * GNU General Public License and visit http://melati.org to obtain the
27   * Melati Software License.
28   *
29   * Feel free to contact the Developers of Melati (http://melati.org),
30   * if you would like to work out a different arrangement than the options
31   * outlined here.  It is our intention to allow Melati to be used by as
32   * wide an audience as possible.
33   *
34   * This program is distributed in the hope that it will be useful,
35   * but WITHOUT ANY WARRANTY; without even the implied warranty of
36   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
37   * GNU General Public License for more details.
38   *
39   * Contact details for copyright holder:
40   *
41   *     Tim Joyce <timj At paneris.org>
42   */
43  
44  package org.melati.util;
45  
46  import java.io.IOException;
47  import java.io.Writer;
48  
49  /**
50   * An abstract <code>Writer</code> for objects that output from Melati.
51   */
52  
53  public abstract class MelatiWriter extends Writer {
54  
55    protected Writer out;
56    protected boolean flush = false;
57    // the flusher sends output to the client every x seconds
58    private Flusher flusher = null;
59    
60    /**
61     * Set flushing true.
62     */
63    public void setFlushingOn() {
64      flush = true;
65      startFlushing();
66    }
67    
68    /**
69     * {@inheritDoc}
70     * @see java.io.Writer#write(char[], int, int)
71     */
72    public void write(char cbuf[], int off, int len) throws IOException {
73      out.write(cbuf, off, len);
74    }
75    
76    /**
77     * {@inheritDoc}
78     * @see java.io.Writer#write(java.lang.String)
79     */
80    public void write(String string) throws IOException {
81      out.write(string);
82    }
83    
84    protected void startFlushing() {
85      if (flush && flusher == null) {
86        flusher = new Flusher(this);
87        flusher.start();
88      }
89    }
90  
91    /**
92     * {@inheritDoc}
93     * @see java.io.Writer#flush()
94     */
95    public void flush() throws IOException {
96      out.flush();
97    }
98  
99    /**
100    * Do nothing in the unbuffered case.
101    * @throws IOException in some implementations
102    */
103   public void reset() throws IOException {
104   }
105 
106   /**
107    * {@inheritDoc}
108    * @see java.io.Writer#close()
109    */
110   public void close() throws IOException {
111     out.close();
112     if (flusher != null) flusher.setStopTask(true);
113   }
114 
115   /**
116    * @return the output Writer
117    */
118   public Writer getWriter()  {
119     return out;
120   }
121 
122 }