1 package org.opentrafficsim.draw.graphs;
2
3 import java.util.concurrent.BlockingQueue;
4 import java.util.concurrent.LinkedBlockingQueue;
5 import java.util.concurrent.TimeUnit;
6
7 import nl.tudelft.simulation.dsol.logger.SimLogger;
8
9 /**
10 * The GrapghUpdater can be used to repeatedly offer a value that is automatically processed in order of offering in a parallel
11 * Thread.
12 * <p>
13 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
14 * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
15 * <p>
16 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 13 okt. 2018 <br>
17 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
18 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
19 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
20 * @param <T> type of value in queue
21 */
22 public class GraphUpdater<T>
23 {
24
25 /** Queue of update times for executing Thread. */
26 private final BlockingQueue<T> queue = new LinkedBlockingQueue<>();
27
28 /**
29 * Constructs and starts a thread that performs each given task from a queue.
30 * @param workerName String; name for the working thread
31 * @param invokingThread Thread; invoking thread, the worker will stop when this thread is interrupted
32 * @param updater Updater<T>; updater to perform with the queued value
33 */
34 public GraphUpdater(final String workerName, final Thread invokingThread, final Updater<T> updater)
35 {
36 new Thread(new Runnable()
37 {
38 /** {@inheritDoc} */
39 @SuppressWarnings({"synthetic-access"})
40 @Override
41 public void run()
42 {
43 while (!invokingThread.isInterrupted())
44 {
45 try
46 {
47 T t = GraphUpdater.this.queue.poll(5, TimeUnit.SECONDS);
48 if (t != null)
49 {
50 updater.update(t);
51 }
52 }
53 catch (InterruptedException exception)
54 {
55 SimLogger.always().error(exception, "Worker {} thread stopped.", workerName);
56 break;
57 }
58 }
59 }
60 }, workerName).start();
61 }
62
63 /**
64 * Offer a next value to the queue.
65 * @param t T; next value to offer to the queue
66 */
67 public final void offer(final T t)
68 {
69 this.queue.offer(t);
70 }
71
72 /**
73 * Functional interface for updates to perform.
74 * <p>
75 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
76 * <br>
77 * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
78 * <p>
79 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 13 okt. 2018 <br>
80 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
81 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
82 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
83 * @param <T> type of value in queue
84 */
85 @FunctionalInterface
86 interface Updater<T>
87 {
88 /**
89 * Perform an update.
90 * @param t T; value to update by
91 */
92 void update(T t);
93 }
94
95 /** {@inheritDoc} */
96 @Override
97 public String toString()
98 {
99 return "GraphUpdater [queue=" + this.queue + "]";
100 }
101
102 }