Package org.djutils.event

Class AbstractEventType

java.lang.Object

org.djutils.event.AbstractEventType

All Implemented Interfaces:

Serializable, EventTypeInterface

Direct Known Subclasses:

EventType, TimedEventType

public abstract class AbstractEventType
extends Object
implements EventTypeInterface

Reference implementation of the EventType. The AbstractEventType is the description of a topic used for the subscription to asynchronous events. Event types are used by EventProducers to show which events they potentially fire. EventTypes are typically defined as static final fields. In order to prevent name clashes for the EventType, the full name of the class from which the EventType was defined (usually in the <clinit>) is added to the equals() and hashCode() methods of the EventType. In that way, EventTypes that are the same will be unique, but EventTypes with just the same name but defined in different classes will be different. This is the abstract class that can be tailored to any event type. Subclasses that extend the AbstractEventType are the EventType for regular events, and TimedEventType for timed events.

Note: the reason why this is important is because remote events that use EventTypes can have multiple versions of the same public static final EventType: one the is defined in the client, and one that is defined via the network. These will have different addresses in memory but they share the same class and name info, so equals() will yield true.

Copyright (c) 2002-2021 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See for project information https://djutils.org. The DJUTILS project is distributed under a three-clause BSD-style license, which can be found at https://djutils.org/docs/license.html. This class was originally part of the DSOL project, see https://simulation.tudelft.nl/dsol/manual.

Author:

Peter Jacobs , Alexander Verbraeck

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
AbstractEventType(String name, MetaData metaData, Class<? extends EventInterface> validEventType)	Construct a new EventType with an explicit type of event that is considered to be a valid event when the event is verified.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object obj)
MetaData	getMetaData()	Retrieve the MetaData that describes the payload of events of this EventType.
String	getName()	Return the event type name.
Class<? extends EventInterface>	getValidEventType()	Retrieve the event type that defines valid events of this EventType, e.g., to indicate a TimedEvent is expected.
int	hashCode()
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

AbstractEventType

public AbstractEventType(String name,
                         MetaData metaData,
                         Class<? extends EventInterface> validEventType)

Construct a new EventType with an explicit type of event that is considered to be a valid event when the event is verified. This can, for instance, be used to verify that a TimedEvent is fired instead of an ordinary event.

Parameters:

name - String; the name of the new eventType. Two values are not appreciated: null and the empty string.

metaData - MetaData; describes the payload of events of the new EventType;

validEventType - Class<? extends EventInterface>; the valid class of events

Method Detail

getName

public String getName()

Return the event type name.

Specified by:

getName in interface EventTypeInterface

Returns:

String; the event type name

getMetaData

public MetaData getMetaData()

Retrieve the MetaData that describes the payload of events of this EventType.

Specified by:

getMetaData in interface EventTypeInterface

Returns:

MetaData; describes the payload of events of this EventType

getValidEventType

public Class<? extends EventInterface> getValidEventType()

Retrieve the event type that defines valid events of this EventType, e.g., to indicate a TimedEvent is expected.

Specified by:

getValidEventType in interface EventTypeInterface

Returns:

Class<EventTypeInterface>; the class of valid events of this event type

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object