1 /************************************************************************
2 * Copyright (c) 2000-2006 The Apache Software Foundation. *
3 * All rights reserved. *
4 * ------------------------------------------------------------------- *
5 * Licensed under the Apache License, Version 2.0 (the "License"); you *
6 * may not use this file except in compliance with the License. You *
7 * may obtain a copy of the License at: *
8 * *
9 * http://www.apache.org/licenses/LICENSE-2.0 *
10 * *
11 * Unless required by applicable law or agreed to in writing, software *
12 * distributed under the License is distributed on an "AS IS" BASIS, *
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or *
14 * implied. See the License for the specific language governing *
15 * permissions and limitations under the License. *
16 ***********************************************************************/
17
18
19 package org.apache.james.util.watchdog;
20
21 import java.io.IOException;
22 import java.io.OutputStream;
23
24 /***
25 * This will reset the Watchdog each time a certain amount of data has
26 * been transferred. This allows us to keep the timeout settings low, while
27 * not timing out during large data transfers.
28 */
29 public class BytesWrittenResetOutputStream extends OutputStream {
30
31 /***
32 * The output stream wrapped by this method
33 */
34 OutputStream out = null;
35
36 /***
37 * The Watchdog to be reset every lengthReset bytes
38 */
39 private Watchdog watchdog;
40
41 /***
42 * The number of bytes that need to be written before the counter is reset.
43 */
44 int lengthReset = 0;
45
46 /***
47 * The number of bytes written since the counter was last reset
48 */
49 int writtenCounter = 0;
50
51 public BytesWrittenResetOutputStream(OutputStream out,
52 Watchdog watchdog,
53 int lengthReset) {
54 this.out = out;
55 this.watchdog = watchdog;
56 this.lengthReset = lengthReset;
57
58 writtenCounter = 0;
59 }
60
61 /***
62 * Write an array of bytes to the stream
63 *
64 * @param b the array of bytes to write to the stream
65 * @param off the index in the array where we start writing
66 * @param len the number of bytes of the array to write
67 *
68 * @throws IOException if an exception is encountered when writing
69 */
70 public void write(byte[] b, int off, int len) throws IOException {
71 out.write(b, off, len);
72 writtenCounter += len;
73
74 if (writtenCounter > lengthReset) {
75 writtenCounter = 0;
76 watchdog.reset();
77 }
78 }
79
80 /***
81 * Write a byte to the stream
82 *
83 * @param b the byte to write to the stream
84 *
85 * @throws IOException if an exception is encountered when writing
86 */
87 public void write(int b) throws IOException {
88 out.write(b);
89 writtenCounter++;
90
91 if (writtenCounter > lengthReset) {
92 writtenCounter = 0;
93 watchdog.reset();
94 }
95 }
96
97 /***
98 * Flush the stream
99 *
100 * @throws IOException if an exception is encountered when flushing
101 */
102 public void flush() throws IOException {
103 out.flush();
104 }
105
106 /***
107 * Close the stream
108 *
109 * @throws IOException if an exception is encountered when closing
110 */
111 public void close() throws IOException {
112 out.close();
113 }
114 }