com.sap.netweaver.bc.rf.util.event
Interface IEventBroker

[contained in: com.sap.netweaver.bc.rf.par - bc.rf.util_api.jar]

All Known Implementing Classes:

EventBroker

public interface IEventBroker

The event broker is a mediator between event senders (IEventSender) and receivers (IEventReceiver). All senders and receivers must register themselfs with a broker. All receivers will receive events from all senders but it is possible to register for different event "templates" (event class and type). Usually a sender will instantiate its own broker and register itself.

Field Summary

static int	PRIO_MAX
static int	PRIO_MIN

Method Summary

IEventList	clearHoldEvents(IEventReceiver receiver) Remove all hold but not yet sent events for the given receiver.
IEventList	getEvents() Returns a list of event templates for all possible events this broker can send (determined by querying all registered senders).
IEventList	getHoldEvents(IEventReceiver receiver) Get all hold but not yet sent events for the given receiver.
ReceiverMode	getMode(IEventReceiver receiver) Get the receiver mode of the receiver, i.e. off, sending and so on.
void	hold(IEventReceiver receiver, boolean collect) TBD: Unknown function.
void	register(IEventReceiver receiver, IEvent template) Registers an event receiver.
void	register(IEventReceiver receiver, IEvent template, IEventMapper mapper) See the general contract of the register(IEventReceiver, IEvent) method.
void	register(IEventReceiver receiver, IEvent template, IEventMapper mapper, int priority, boolean async) See the general contract of the register(IEventReceiver, IEvent, IEventMapper) and register(IEventReceiver, IEvent, int, boolean) method.
void	register(IEventReceiver receiver, IEvent template, int priority, boolean async) See the general contract of the register(IEventReceiver, IEvent) method.
void	register(IEventSender sender) Registers an event sender instance.
void	resume(IEventReceiver receiver) Resumes a previously suspended event receiver.
void	send(IEvent event, IEventSender sender) Sends the specified event to all receivers that have registered for this kind of event.
void	suspend(IEventReceiver receiver) Suspend the event receiver.
void	unregister(IEventReceiver receiver, IEvent template) Unregisteres an event receiver instance.
void	unregister(IEventSender sender) Unregisteres an event sender instance.

Field Detail

PRIO_MAX

public static final int PRIO_MAX

PRIO_MIN

public static final int PRIO_MIN

Method Detail

send

public void send(IEvent event,
                 IEventSender sender)
          throws BaseException

Sends the specified event to all receivers that have registered for this kind of event.

Parameters:

event - event to be sent

sender - event sender instance sending the event

Throws:

BaseException - when the event sender is not registered

register

public void register(IEventSender sender)
              throws BaseException

Registers an event sender instance.

Parameters:

sender - event sender to be registered

Throws:

BaseException - when the registration fails

register

public void register(IEventReceiver receiver,
                     IEvent template)
              throws BaseException

Registers an event receiver. The receiver will only receive events which match the template event. This depends on the matching rules implemented in the events IEvent.isLike(com.sap.netweaver.bc.rf.util.event.IEvent) method. Usually the event's instance and type are relevant. It is allowed to register the same event receiver instance several times with different templates.

Parameters:

receiver - event receiver to be registered

template - event template on which the event receiver will receive events

Throws:

BaseException - when the registration fails

register

public void register(IEventReceiver receiver,
                     IEvent template,
                     IEventMapper mapper)
              throws BaseException

See the general contract of the register(IEventReceiver, IEvent) method. This regstration method has an additional IEventMapper argument, i.e. that the mapper will be called prior to giving the event to the receiver.

Parameters:

receiver - event receiver to be registered

template - event template on which the event receiver will receive events

mapper - event mapper to be called prior to giving the event to the receiver

Throws:

BaseException - when the registration fails

See Also:

IEventMapper

register

public void register(IEventReceiver receiver,
                     IEvent template,
                     int priority,
                     boolean async)
              throws BaseException

See the general contract of the register(IEventReceiver, IEvent) method. This regstration method has two additional arguments for priority and asynchronous events.

The priority controls the order of multible receivers which have registered for the same event(s). Receivers with higher priority (smaller values) will receive an event before receivers with lower priority (greater values).

An event receiver can choose to receive events asynchronously. This means that a dedicated event queue and sender thread is created for each receiver and template. The event sender will not be blocked, that means the send() method puts the event into the queue and returns immediatelly.

Parameters:

receiver - event receiver to be registered

template - event template on which the event receiver will receive events

priority - priority of this receiver and template

async - true when the receiver whould receive the events on a seperate thread

Throws:

BaseException - when the registration fails

register

public void register(IEventReceiver receiver,
                     IEvent template,
                     IEventMapper mapper,
                     int priority,
                     boolean async)
              throws BaseException

See the general contract of the register(IEventReceiver, IEvent, IEventMapper) and register(IEventReceiver, IEvent, int, boolean) method.

Parameters:

receiver - event receiver to be registered

template - event template on which the event receiver will receive events

mapper - event mapper to be called prior to giving the event to the receiver

priority - priority of this receiver and template

async - true when the receiver whould receive the events on a seperate thread

Throws:

BaseException - when the registration fails

See Also:

IEventMapper

unregister

public void unregister(IEventSender sender)
                throws BaseException

Unregisteres an event sender instance.

Parameters:

sender - event sender to be unregistered

Throws:

BaseException - when the unregistration fails

unregister

public void unregister(IEventReceiver receiver,
                       IEvent template)
                throws BaseException

Unregisteres an event receiver instance.

Parameters:

receiver - event receiver to be unregistered

template - event template on which the event receiver will no longer receive events

Throws:

BaseException - when the unregistration fails

suspend

public void suspend(IEventReceiver receiver)

Suspend the event receiver. The broker will stop delivering any events until resume(com.sap.netweaver.bc.rf.util.event.IEventReceiver) is called.

Parameters:

receiver - event receiver

resume

public void resume(IEventReceiver receiver)

Resumes a previously suspended event receiver. The broker will continue delivering events to the receiver.

Parameters:

receiver - event receiver

hold

public void hold(IEventReceiver receiver,
                 boolean collect)

TBD: Unknown function.

Parameters:

receiver - TBD: Unknown parameter

collect - TBD: Unknown parameter

getMode

public ReceiverMode getMode(IEventReceiver receiver)

Get the receiver mode of the receiver, i.e. off, sending and so on.

Parameters:

receiver - event receiver

Returns:

receiver mode of the receiver

See Also:

ReceiverMode

getHoldEvents

public IEventList getHoldEvents(IEventReceiver receiver)

Get all hold but not yet sent events for the given receiver.

Parameters:

receiver - event receiver

Returns:

all hold but not yet sent events for the given receiver

clearHoldEvents

public IEventList clearHoldEvents(IEventReceiver receiver)

Remove all hold but not yet sent events for the given receiver.

Parameters:

receiver - event receiver

Returns:

all hold but not yet sent events for the given receiver

getEvents

public IEventList getEvents()

Returns a list of event templates for all possible events this broker can send (determined by querying all registered senders). The event instances contained in the list are "templates", that means the event parameter is not relevant.

Returns:

list of event templates for all possible events this broker can send