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 org.djutils.logger.CategoryLogger;
8
9 /**
10 * The GraphUpdater 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) 2013-2023 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
14 * BSD-style license. See <a href="https://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
15 * </p>
16 * @author <a href="https://github.com/averbraeck">Alexander Verbraeck</a>
17 * @author <a href="https://tudelft.nl/staff/p.knoppers-1">Peter Knoppers</a>
18 * @author <a href="https://dittlab.tudelft.nl">Wouter Schakel</a>
19 * @param <T> type of value in queue
20 */
21 public class GraphUpdater<T>
22 {
23
24 /** Queue of update times for executing Thread. */
25 private final BlockingQueue<T> queue = new LinkedBlockingQueue<>();
26
27 /**
28 * Constructs and starts a thread that performs each given task from a queue.
29 * @param workerName String; name for the working thread
30 * @param invokingThread Thread; invoking thread, the worker will stop when this thread is interrupted
31 * @param updater Updater<T>; updater to perform with the queued value
32 */
33 public GraphUpdater(final String workerName, final Thread invokingThread, final Updater<T> updater)
34 {
35 new Thread(new Runnable()
36 {
37 /** {@inheritDoc} */
38 @SuppressWarnings({"synthetic-access"})
39 @Override
40 public void run()
41 {
42 while (!invokingThread.isInterrupted())
43 {
44 try
45 {
46 T t = GraphUpdater.this.queue.poll(5, TimeUnit.SECONDS);
47 if (t != null)
48 {
49 updater.update(t);
50 }
51 }
52 catch (InterruptedException exception)
53 {
54 CategoryLogger.always().error(exception, "Worker {} thread stopped.", workerName);
55 break;
56 }
57 }
58 }
59 }, workerName).start();
60 }
61
62 /**
63 * Offer a next value to the queue.
64 * @param t T; next value to offer to the queue
65 */
66 public final void offer(final T t)
67 {
68 this.queue.offer(t);
69 }
70
71 /**
72 * Functional interface for updates to perform.
73 * <p>
74 * Copyright (c) 2013-2023 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
75 * <br>
76 * BSD-style license. See <a href="https://opentrafficsim.org/docs/license.html">OpenTrafficSim License</a>.
77 * </p>
78 * @author <a href="https://github.com/averbraeck">Alexander Verbraeck</a>
79 * @author <a href="https://tudelft.nl/staff/p.knoppers-1">Peter Knoppers</a>
80 * @author <a href="https://dittlab.tudelft.nl">Wouter Schakel</a>
81 * @param <T> type of value in queue
82 */
83 @FunctionalInterface
84 interface Updater<T>
85 {
86 /**
87 * Perform an update.
88 * @param t T; value to update by
89 */
90 void update(T t);
91 }
92
93 /** {@inheritDoc} */
94 @Override
95 public String toString()
96 {
97 return "GraphUpdater [queue=" + this.queue + "]";
98 }
99
100 }