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5 * regarding copyright ownership. The ASF licenses this file *
6 * to you under the Apache License, Version 2.0 (the *
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10 * http://www.apache.org/licenses/LICENSE-2.0 *
11 * *
12 * Unless required by applicable law or agreed to in writing, *
13 * software distributed under the License is distributed on an *
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
15 * KIND, either express or implied. See the License for the *
16 * specific language governing permissions and limitations *
17 * under the License. *
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19
20
21 package org.apache.james.util;
22
23 import org.apache.avalon.cornerstone.services.scheduler.TimeScheduler;
24
25 import java.io.IOException;
26 import java.io.InputStream;
27
28 /***
29 * This will reset the scheduler each time a certain amount of data has
30 * been transfered. This allows us to keep the timeout settings low, while
31 * not timing out during large data transfers.
32 */
33 public class SchedulerNotifyInputStream extends InputStream {
34
35 /***
36 * The wrapped InputStream
37 */
38 InputStream in = null;
39
40 /***
41 * The scheduler managing the trigger to be reset by this stream
42 */
43 TimeScheduler scheduler = null;
44
45 /***
46 * The name of the trigger
47 */
48 String triggerName = null;
49
50 /***
51 * The number of bytes that need to be read before the counter is reset.
52 */
53 int lengthReset = 0;
54
55 /***
56 * The number of bytes read since the counter was last reset
57 */
58 int readCounter = 0;
59
60 /***
61 * @param in the InputStream to be wrapped by this stream
62 * @param scheduler the TimeScheduler managing the trigger to be reset by this stream
63 * @param triggerName the name of the particular trigger to be reset by this stream
64 * @param lengthReset the number of bytes to be read in between trigger resets
65 */
66 public SchedulerNotifyInputStream(InputStream in,
67 TimeScheduler scheduler, String triggerName, int lengthReset) {
68 this.in = in;
69 this.scheduler = scheduler;
70 this.triggerName = triggerName;
71 this.lengthReset = lengthReset;
72
73 readCounter = 0;
74 }
75
76 /***
77 * Read an array of bytes from the stream
78 *
79 * @param b the array of bytes to read from the stream
80 * @param off the index in the array where we start writing
81 * @param len the number of bytes of the array to read
82 *
83 * @return the number of bytes read
84 *
85 * @throws IOException if an exception is encountered when reading
86 */
87 public int read(byte[] b, int off, int len) throws IOException {
88 int l = in.read(b, off, len);
89 readCounter += l;
90
91 if (readCounter > lengthReset) {
92 readCounter -= lengthReset;
93 scheduler.resetTrigger(triggerName);
94 }
95
96 return l;
97 }
98
99 /***
100 * Read a byte from the stream
101 *
102 * @return the byte read from the stream
103 * @throws IOException if an exception is encountered when reading
104 */
105 public int read() throws IOException {
106 int b = in.read();
107 readCounter++;
108
109 if (readCounter > lengthReset) {
110 readCounter -= lengthReset;
111 scheduler.resetTrigger(triggerName);
112 }
113
114 return b;
115 }
116
117 /***
118 * Close the stream
119 *
120 * @throws IOException if an exception is encountered when closing
121 */
122 public void close() throws IOException {
123 in.close();
124 }
125 }