seda.sandStorm.lib.aSocket
Interface SelectSourceIF

All Superinterfaces:

SourceIF

All Known Implementing Classes:

NIOSelectSource, SelectSource

public interface SelectSourceIF
extends SourceIF

A SelectSource is an implementation of SourceIF which pulls events from the operating system via the NBIO SelectSet interface. This can be thought of as a 'shim' which turns a SelectSet into a SourceIF.

SelectSource can also "balances" the set of events returned on subsequent calls to dequeue, in order to avoid biasing the servicing of underlying O/S events to a particular order. This feature can be disabled by creating a SelectSource with the boolean flag 'do_balance'.

Method Summary

void	deregister(java.lang.Object sel) Deregister a SelectItem with this SelectSource.
int	numActive() Return the number of active SelectItems registered with the SelectSource.
int	numRegistered() Return the number of SelectItems registered with the SelectSource.
void	register(java.lang.Object sel) Register a SelectItem with the SelectSource.
java.lang.Object	register(java.lang.Object sc, int ops)
int	size() Return the number of elements waiting in the queue (that is, which don't require a SelectSet poll operation to retrieve).
void	update() Must be called if the 'events' mask of any SelectItem registered with this SelectSource changes.
void	update(java.lang.Object sel) Must be called if the 'events' mask of this SelectItem (which must be registered with this SelectSource) changes.

Methods inherited from interface seda.sandStorm.api.SourceIF

blocking_dequeue_all, blocking_dequeue, blocking_dequeue, dequeue_all, dequeue, dequeue

Method Detail

register

void register(java.lang.Object sel)

Register a SelectItem with the SelectSource. The SelectItem should generally correspond to a Selectable along with a set of event flags that we wish this SelectSource to test for.

The user is allowed to modify the event flags in the SelectItem directly (say, to cause the SelectSource ignore a given SelectItem for the purposes of future calls to one of the dequeue methods). However, modifying the event flags may not be synchronous with calls to dequeue - generally because SelectSource maintains a cache of recently-received events.

See Also:

Selectable

register

java.lang.Object register(java.lang.Object sc,
                          int ops)

deregister

void deregister(java.lang.Object sel)

Deregister a SelectItem with this SelectSource. Note that after calling deregister, subsequent calls to dequeue may in fact return this SelectItem as a result. This is because the SelectQueue internally caches results.

update

void update()

Must be called if the 'events' mask of any SelectItem registered with this SelectSource changes. Pushes event mask changes down to the underlying event-dispatch mechanism.

update

void update(java.lang.Object sel)

Must be called if the 'events' mask of this SelectItem (which must be registered with this SelectSource) changes. Pushes event mask changes down to the underlying event-dispatch mechanism.

numRegistered

int numRegistered()

Return the number of SelectItems registered with the SelectSource.

numActive

int numActive()

Return the number of active SelectItems registered with the SelectSource. An active SelectItem is one defined as having a non-zero events interest mask.

size

int size()

Return the number of elements waiting in the queue (that is, which don't require a SelectSet poll operation to retrieve).

Specified by:

size in interface SourceIF