Package org.glassfish.grizzly.comet

Interface CometHandler<E>

All Known Implementing Classes:

DefaultCometHandler, DefaultConcurrentCometHandler

public interface CometHandler<E>

This interface represents a suspended connection (or response). Passing an instance of this class to CometContext.addCometHandler(CometHandler) automatically tells Grizzly Comet to suspend the underlying connection and to avoid committing the response. Since the response is not committed, the connection is considered as suspended and can be resumed later when an event happens by invoking CometContext.resumeCometHandler(CometHandler), from onEvent(org.glassfish.grizzly.comet.CometEvent). CometContext.resumeCometHandler(CometHandler), resume the connection by committing the response. As an example, a browser icons will spins when a connection is suspended, as the complete response hasn't been sent back.

Components that implement this interface will be notified Object.notify() is invoked or when the CometContext.getExpirationDelay() expires.

Method Summary

Modifier and Type	Method	Description
CometContext<E>	getCometContext()
org.glassfish.grizzly.http.server.Response	getResponse()
void	onEvent(CometEvent event)	Receive CometEvent notification.
void	onInitialize(CometEvent event)	Receive CometEvent notification when Grizzly is about to suspend the connection.
void	onInterrupt(CometEvent event)	Receive CometEvent notification when the underlying tcp communication is resumed by Grizzly.
void	onTerminate(CometEvent event)	Receive CometEvent notification when the response is resumed by a CometHandler or by the CometContext
void	setCometContext(CometContext<E> context)
void	setResponse(org.glassfish.grizzly.http.server.Response response)

Method Details

getResponse

org.glassfish.grizzly.http.server.Response getResponse()

Returns:

the response associated with the handler.

setResponse

void setResponse(org.glassfish.grizzly.http.server.Response response)

getCometContext

CometContext<E> getCometContext()

setCometContext

void setCometContext(CometContext<E> context)

onEvent

void onEvent(CometEvent event)
      throws IOException

Receive CometEvent notification. This method will be invoked every time a CometContext.notify(E) is invoked. The CometEvent will contains the message that can be pushed back to the remote client, cached or ignored. This method can also be used to resume a connection once a notified by invoking CometContext.resumeCometHandler(org.glassfish.grizzly.comet.CometHandler).
its not optimal to flush outputstream in this method for long polling, flush is performed in each CometContext.resume call.
flushing multiple times can fragment the data into several tcp packets, that leads to extra IO and overhead in general due to client ack for each packet etc.

Throws:

IOException

onInitialize

void onInitialize(CometEvent event)
           throws IOException

Receive CometEvent notification when Grizzly is about to suspend the connection. This method is always invoked during the processing of CometContext.addCometHandler(org.glassfish.grizzly.comet.CometHandler<E>) operations.

Throws:

IOException

onTerminate

void onTerminate(CometEvent event)
          throws IOException

Receive CometEvent notification when the response is resumed by a CometHandler or by the CometContext

Throws:

IOException

onInterrupt

void onInterrupt(CometEvent event)
          throws IOException

Receive CometEvent notification when the underlying tcp communication is resumed by Grizzly. This happens when the CometContext.setExpirationDelay(long) expires or when the remote client close the connection.

Throws:

IOException