org.apache.river.jeri.internal.runtime

Class SelectionManager

java.lang.Object

org.apache.river.jeri.internal.runtime.SelectionManager

public final class SelectionManager
extends Object

A SelectionManager provides an event dispatching layer on top of the java.nio.Selector and java.nio.SelectableChannel abstractions; it manages one-shot registrations of interest in I/O readiness events and dispatching notifications of such events to registered callback objects. SelectionManager is designed to support multiple select/dispatch threads to allow for improved I/O concurrency on symmetric multiprocessor systems. If interest in a particular I/O event is (re-)registered while there is a blocking select operation in progress, that select operation must be woken up so that it can take the new interest into account; this wakeup is achieved by writing a byte to an internal pipe that is registered with the underlying selector. A current limitation of this API is that it does not allow an executing callback to yield control in such a way that it will be scheduled to execute again without another I/O readiness event occurring. Therefore, data that gets read during a callback must also get processed, unless such processing depends on more data that has not yet been read (like the remainder of a partial message).

This implementation uses the Logger named org.apache.river.jeri.internal.runtime.SelectionManager to log information at the following levels:

Level	Description
HANDLED	I/O exception caught from select operation

Author:

Sun Microsystems, Inc.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	SelectionManager.Key A Key represents a given SelectableChannel's registration with this SelectionManager.
static interface	SelectionManager.SelectionHandler SelectionHandler is the callback interface for an object that will process an I/O readiness event that has been detected by a SelectionManager.

Constructor Summary

Constructors

Constructor and Description
SelectionManager() Creates a new SelectionManager.

Method Summary

Modifier and Type	Method and Description
SelectionManager.Key	register(SelectableChannel channel, SelectionManager.SelectionHandler handler) Registers the given SelectableChannel with this SelectionManager.

Methods inherited from class java.lang.Object

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

Constructor Detail

SelectionManager

public SelectionManager()
                 throws IOException

Creates a new SelectionManager. REMIND: Is this necessary, or should we just provide access to a singleton instance?

Throws:

IOException

Method Detail

register

public SelectionManager.Key register(SelectableChannel channel,
                                     SelectionManager.SelectionHandler handler)

Registers the given SelectableChannel with this SelectionManager. After registration, the returned Key's renewInterestMask method may be used to register one-shot interest in particular I/O events.