Package opencard.core.event

Class EventGenerator

java.lang.Object

opencard.core.event.EventGenerator

All Implemented Interfaces:

java.lang.Runnable, Observer

public final class EventGenerator
extends java.lang.Object
implements Observer, java.lang.Runnable

The EventGenerator singleton acts as a generator and multicaster for card terminal events. The singleton instance can be obtained by calling the static method getGenerator. It periodically polls the terminals and generates CARD_INSERTED or CARD_REMOVED events if it detects a card insertion or removal, respectively. The generated events are sent to all CTListeners which have been registered using the method addCTListener. If not interested in card terminal events any longer, CTListeners can remove themselves from the notification list of the registry by calling the method removeCTListener. For the case that cards were inserted before an application was started, the method createEventsForPresentCards creates events for inserted cards a posteriori.

See Also:

CardTerminalEvent, CTListener, CardTerminal, CardTerminalRegistry

Method Summary

Modifier and Type	Method	Description
void	addCTListener(CTListener listener)	Adds a CTListener.
void	createEventsForPresentCards(CTListener ctListener)	Generates events for cards which are already inserted.
static EventGenerator	getGenerator()	Gets the unique instance of CardTerminalRegistry.
int	getPollInterval()	Gets the duration of the poll interval in ms.
void	removeAllCTListener()
void	removeAllPollables()
void	removeCTListener(CTListener ctListener)	Removes a CTListener.
void	run()	Periodically checks all Pollable terminals.
void	setPollInterval(int duration)	Sets the poll interval in ms
void	updateCards(CardTerminal terminal, int slotID, boolean cardInserted)	Notify listeners that a card was inserted into or removed from a slot of a terminal.
boolean	updateTerminals(Pollable p, boolean terminalAdded)	.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getGenerator

public static EventGenerator getGenerator()

Gets the unique instance of CardTerminalRegistry. (Singleton Pattern)

Returns:

The card terminal registry singleton.

addCTListener

public void addCTListener(CTListener listener)

Adds a CTListener.

Parameters:

listener - The CTListener to be added.

See Also:

removeCTListener(CTListener)

createEventsForPresentCards

public void createEventsForPresentCards(CTListener ctListener)
                                 throws CardTerminalException

Generates events for cards which are already inserted. This method should be called when using the event-driven paradigm (in contrast to the procedural waitForCard () approach) and the application needs to handle cards that are already inserted. This method iterates over all registered terminals.

Parameters:

ctListener - the Card Terminal Listener to which the events shall be sent.

Throws:

CardTerminalException - thrown in case of errors in a registered CardTerminal.

removeCTListener

public void removeCTListener(CTListener ctListener)

Removes a CTListener.

Parameters:

ctListener - The CTListener to be removed.

See Also:

addCTListener(CTListener)

removeAllCTListener

public void removeAllCTListener()

removeAllPollables

public void removeAllPollables()

setPollInterval

public void setPollInterval(int duration)

Sets the poll interval in ms

Parameters:

duration - in ms

getPollInterval

public int getPollInterval()

Gets the duration of the poll interval in ms.

Returns:

the poll interval duration in ms

run

public void run()

Periodically checks all Pollable terminals. The terminals implementation must then make sure to generate the proper events whenever they detect that a card was inserted or removed from one of their slots.

Specified by:

run in interface java.lang.Runnable

updateCards

public void updateCards(CardTerminal terminal,
                        int slotID,
                        boolean cardInserted)

Notify listeners that a card was inserted into or removed from a slot of a terminal.

Specified by:

updateCards in interface Observer

Parameters:

terminal - terminal where a card was inserted/removed

slotID - slot where a card was inserted/removed

cardInserted - true if a card was inserted, false, if a card was removed

updateTerminals

public boolean updateTerminals(Pollable p,
                               boolean terminalAdded)

. Keep track of pollable terminals, used by CardTerminalRegistry

Specified by:

updateTerminals in interface Observer

Parameters:

p - terminal that was added/removed to the registry

terminalAdded - true if a terminal was added. False, if a terminal was removed.