1 /*
2 * $Source$
3 * $Revision$
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 /** Write with exception conversion */
85 public void output(String s) {
86 try {
87 out.write(s);
88 } catch (IOException e) {
89 throw new MelatiIOException(e);
90 }
91 }
92
93 protected void startFlushing() {
94 if (flush && flusher == null) {
95 flusher = new Flusher(this);
96 flusher.start();
97 }
98 }
99
100 /**
101 * {@inheritDoc}
102 * @see java.io.Writer#flush()
103 */
104 public void flush() throws IOException {
105 out.flush();
106 }
107
108 /**
109 * Do nothing in the unbuffered case.
110 * @throws IOException in some implementations
111 */
112 public void reset() throws IOException {
113 }
114
115 /**
116 * {@inheritDoc}
117 * @see java.io.Writer#close()
118 */
119 public void close() throws IOException {
120 out.close();
121 if (flusher != null) flusher.setStopTask(true);
122 }
123
124 /**
125 * @return the output Writer
126 */
127 public Writer getWriter() {
128 return out;
129 }
130
131 }