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Code - Class EDU.oswego.cs.dl.util.concurrent.TimedCallable

1 /*
2   TimedCallable.java
3
4   Originally written by Joseph Bowbeer and released into the public domain.
5   This may be used for any purposes whatsoever without acknowledgment.
6
7   Originally part of jozart.swingutils.
8   Adapted by Doug Lea for util.concurrent.
9
10   History:
11   Date Who What
12   11dec1999 dl Adapted for util.concurrent
13
14 */
15
16 package EDU.oswego.cs.dl.util.concurrent;
17
18 /**
19 * TimedCallable runs a Callable function for a given length of time.
20 * The function is run in its own thread. If the function completes
21 * in time, its result is returned; otherwise the thread is interrupted
22 * and an InterruptedException is thrown.
23 * <p>
24 * Note: TimedCallable will always return within the given time limit
25 * (modulo timer inaccuracies), but whether or not the worker thread
26 * stops in a timely fashion depends on the interrupt handling in the
27 * Callable function's implementation.
28 *
29 * @author Joseph Bowbeer
30 * @version 1.0
31 *
32 * <p>[<a HREF="http://gee.cs.oswego.edu/dl/classes/EDU/oswego/cs/dl/util/concurrent/intro.html"> Introduction to this package. </a>]
33
34 */
35
36 public class TimedCallable extends ThreadFactoryUser implements Callable {
37
38   private final Callable function;
39   private final long millis;
40
41   public TimedCallable(Callable function, long millis) {
42     this.function = function;
43     this.millis = millis;
44   }
45
46   public Object call() throws Exception {
47
48     FutureResult result = new FutureResult();
49
50     Thread thread = getThreadFactory().newThread(result.setter(function));
51
52     thread.start();
53
54     try {
55       return result.timedGet(millis);
56     }
57     catch (InterruptedException ex) {
58       /* Stop thread if we were interrupted or timed-out
59          while waiting for the result. */
60       thread.interrupt();
61       throw ex;
62     }
63   }
64 }
65