1 package org.opentrafficsim.core.perception.collections;
2
3 import java.util.HashMap;
4 import java.util.Map;
5
6 import org.djunits.value.vdouble.scalar.Time;
7 import org.opentrafficsim.core.perception.HistoryManager;
8
9 /**
10 * HashMap-valued historical state. The current hash map is always maintained, and past states of the hash map are obtained by
11 * applying the events between now and the requested time in reverse.<br>
12 * <br>
13 * The set views returned by this class are unmodifiable.
14 * <p>
15 * Copyright (c) 2013-2019 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
16 * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
17 * <p>
18 * @version $Revision$, $LastChangedDate$, by $Author$, initial version 3 feb. 2018 <br>
19 * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
20 * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
21 * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
22 * @param <K> key type
23 * @param <V> value type
24 */
25 public class HistoricalHashMap<K, V> extends AbstractHistoricalMap<K, V, HashMap<K, V>>
26 {
27
28 /**
29 * Constructor.
30 * @param historyManager HistoryManager; history manager
31 */
32 public HistoricalHashMap(final HistoryManager historyManager)
33 {
34 super(historyManager, new HashMap<>());
35 }
36
37 /**
38 * Constructor.
39 * @param historyManager HistoryManager; history manager
40 * @param m Map<? extends K, ? extends V>; initial map
41 */
42 public HistoricalHashMap(final HistoryManager historyManager, final Map<? extends K, ? extends V> m)
43 {
44 super(historyManager, new HashMap<>(m));
45 }
46
47 /** {@inheritDoc} */
48 @Override
49 public HashMap<K, V> get()
50 {
51 return getMap();
52 }
53
54 /** {@inheritDoc} */
55 @Override
56 public HashMap<K, V> get(final Time time)
57 {
58 if (isLastState(time))
59 {
60 return getMap();
61 }
62 return fill(time, new HashMap<>());
63 }
64
65 /** {@inheritDoc} */
66 @Override
67 public String toString()
68 {
69 return "HistoricalHashMap [current=" + getMap() + "]";
70 }
71
72 }