1 package org.djutils.event;
2
3 import java.io.Serializable;
4
5 import org.djutils.metadata.MetaData;
6
7 /**
8 * The Event class forms the reference implementation for the EventInterface. Because events are often sent over the network,
9 * the interface demands that source of the event and its content are serializable. It is the responsibility of the programmer,
10 * though, that the <b>fields</b> of the sourceId and content are serializable as well.
11 * <p>
12 * Copyright (c) 2002-2021 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
13 * for project information <a href="https://djutils.org" target="_blank"> https://djutils.org</a>. The DJUTILS project is
14 * distributed under a three-clause BSD-style license, which can be found at
15 * <a href="https://djutils.org/docs/license.html" target="_blank"> https://djutils.org/docs/license.html</a>. This class was
16 * originally part of the DSOL project, see <a href="https://simulation.tudelft.nl/dsol/manual" target="_blank">
17 * https://simulation.tudelft.nl/dsol/manual</a>.
18 * </p>
19 * @author <a href="https://www.linkedin.com/in/peterhmjacobs">Peter Jacobs </a>
20 * @author <a href="https://www.tudelft.nl/averbraeck">Alexander Verbraeck</a>
21 */
22 public class AbstractEvent implements EventInterface
23 {
24 /** The default serial version UID for serializable classes. */
25 private static final long serialVersionUID = 20140826L;
26
27 /** The type of the event. */
28 private final EventTypeInterface type;
29
30 /** The content of the event. */
31 private final Serializable content;
32
33 /** The source id of an event. */
34 private final Serializable sourceId;
35
36 /**
37 * Construct a new Event, where compliance with the metadata is verified.
38 * @param type EventTypeInterface; the name of the Event.
39 * @param sourceId Serializable; the source id of the sender
40 * @param content Serializable; the content of the event
41 */
42 public AbstractEvent(final EventTypeInterface type, final Serializable sourceId, final Serializable content)
43 {
44 this(type, sourceId, content, true);
45 }
46
47 /**
48 * Construct a new Event, with a choice to verify compliance with metadata.
49 * @param type EventTypeInterface; the name of the Event.
50 * @param sourceId Serializable; the source id of the sender
51 * @param content Serializable; the content of the event
52 * @param verifyMetaData boolean; whether to verify the compliance with metadata or not
53 */
54 public AbstractEvent(final EventTypeInterface type, final Serializable sourceId, final Serializable content,
55 final boolean verifyMetaData)
56 {
57 this.type = type;
58 this.sourceId = sourceId;
59 this.content = content;
60 if (verifyMetaData && null != this.type)
61 {
62 MetaData metaData = type.getMetaData();
63 if (null != metaData)
64 {
65 if ((null != content) && !(content instanceof Object[]))
66 {
67 metaData.verifyComposition(content);
68 }
69 else
70 {
71 metaData.verifyComposition((Object[]) content);
72 }
73 }
74 }
75 }
76
77 /** {@inheritDoc} */
78 @Override
79 public final Serializable getSourceId()
80 {
81 return this.sourceId;
82 }
83
84 /** {@inheritDoc} */
85 @Override
86 public final Serializable getContent()
87 {
88 return this.content;
89 }
90
91 /** {@inheritDoc} */
92 @Override
93 public EventTypeInterface getType()
94 {
95 return this.type;
96 }
97
98 /** {@inheritDoc} */
99 @Override
100 public int hashCode()
101 {
102 final int prime = 31;
103 int result = 1;
104 result = prime * result + ((this.content == null) ? 0 : this.content.hashCode());
105 result = prime * result + ((this.sourceId == null) ? 0 : this.sourceId.hashCode());
106 result = prime * result + ((this.type == null) ? 0 : this.type.hashCode());
107 return result;
108 }
109
110 /** {@inheritDoc} */
111 @Override
112 @SuppressWarnings("checkstyle:needbraces")
113 public boolean equals(final Object obj)
114 {
115 if (this == obj)
116 return true;
117 if (obj == null)
118 return false;
119 if (getClass() != obj.getClass())
120 return false;
121 AbstractEvent../org/djutils/event/AbstractEvent.html#AbstractEvent">AbstractEvent other = (AbstractEvent) obj;
122 if (this.content == null)
123 {
124 if (other.content != null)
125 return false;
126 }
127 else if (!this.content.equals(other.content))
128 return false;
129 if (this.sourceId == null)
130 {
131 if (other.sourceId != null)
132 return false;
133 }
134 else if (!this.sourceId.equals(other.sourceId))
135 return false;
136 if (this.type == null)
137 {
138 if (other.type != null)
139 return false;
140 }
141 else if (!this.type.equals(other.type))
142 return false;
143 return true;
144 }
145
146 }