org.exolab.core.messenger
Class PacketConnection

java.lang.Object
  org.exolab.core.messenger.PacketConnection

All Implemented Interfaces:

Connection

public class PacketConnection

extends java.lang.Object

implements Connection

A PacketConnection is a Connection that minimises resource usage.

This is achieved by:

• Restricting the number of physical connections by sharing them between multiple Channel instances
• Breaking large messages into packets, allowing multiple channels to use the connection at the same time
• Optionally restricting the number of packets used by the connection, to avoid OutOfMemoryError exceptions being thrown during high activity on the connection

Version:

$Revision: 1.5 $ $Date: 2003/06/09 06:28:40 $

Author:

Tim Anderson

See Also:

ConnectionEventListener, PacketChannel, PacketQueue, PacketPool, Multiplexer, Demultiplexer

Constructor Summary

PacketConnection(ManagedPacketConnection owner, int connectionId)
Construct a new PacketConnection

Method Summary

void	accept(java.lang.String name, ChannelHandler handler) Register a handler to accept channel connections for the specified name.
void	accept(java.lang.String name, ChannelListener listener) Register a handler to accept a single channel connection for the specified name, and bind the listener to it This method returns immediately.
void	addConnectionEventListener(ConnectionEventListener listener) Add a listener for connection events
void	close() Close the connection.
void	close(java.lang.String name) Stop accepting requests on the specified channel
protected void	closed(PacketChannel channel)
protected PacketChannel	createChannel(int channelId, int destinationId)
protected void	doClose() Performs the actual connection closure, without notifying registered listeners
protected void	ensureOpen()
protected Channel	getChannel(int channelId) Returns the channel for the give channel identifier
int	getConnectionId() Return the unique identifier for this connection
protected int	getNextChannelId()
protected PacketQueue	getOutputQueue() Returns the queue of packets to be streamed down the physical connection
protected org.exolab.core.messenger.PacketPool	getPool() Returns the pool of free packets
protected ThreadPool	getThreadPool() Returns the thread pool
Channel	open(java.lang.String name) Open a channel
void	removeConnectionEventListener(ConnectionEventListener listener) Remove a listener of connection events

Methods inherited from class java.lang.Object

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

Constructor Detail

PacketConnection

public PacketConnection(ManagedPacketConnection owner,
                        int connectionId)
                 throws java.rmi.RemoteException

Construct a new PacketConnection

Parameters:

owner - the managed connection that owns this

connectionId - the connection identifier

Throws:

java.lang.IllegalArgumentException - if owner is null

java.rmi.RemoteException - if the connection can't be initialised

Method Detail

getConnectionId

public int getConnectionId()

Return the unique identifier for this connection

Returns:

the identifier for this connection

open

public Channel open(java.lang.String name)
             throws java.rmi.RemoteException

Open a channel

Specified by:

open in interface Connection

Parameters:

name - the name of the channel

Returns:

the open channel

Throws:

java.rmi.RemoteException - if the channel can't be opened

ConnectionClosedException - if the connection is closed

InvalidChannelException - if the channel doesn't exist

accept

public void accept(java.lang.String name,
                   ChannelHandler handler)
            throws java.rmi.RemoteException

Register a handler to accept channel connections for the specified name.
This method returns immediately.

Specified by:

accept in interface Connection

Parameters:

name - the channel name to listen on

handler - the handler to pass new channels to

Throws:

java.rmi.RemoteException - if an error occurs accepting channels

ConnectionClosedException - if the connection is closed

java.lang.IllegalArgumentException - if any argument is null

accept

public void accept(java.lang.String name,
                   ChannelListener listener)
            throws java.rmi.RemoteException

Register a handler to accept a single channel connection for the specified name, and bind the listener to it
This method returns immediately.

Specified by:

accept in interface Connection

Parameters:

name - the channel name to listen on

listener - the listener to handle requests on the channel

Throws:

java.rmi.RemoteException - if an error occurs accepting channels

ConnectionClosedException - if the connection is closed

java.lang.IllegalArgumentException - if any argument is null

close

public void close(java.lang.String name)

Stop accepting requests on the specified channel

Specified by:

close in interface Connection

Parameters:

name - the channel name

Throws:

java.lang.IllegalArgumentException - if name is null

addConnectionEventListener

public void addConnectionEventListener(ConnectionEventListener listener)

Add a listener for connection events

Specified by:

addConnectionEventListener in interface Connection

Parameters:

listener - the listener to add

removeConnectionEventListener

public void removeConnectionEventListener(ConnectionEventListener listener)

Remove a listener of connection events

Specified by:

removeConnectionEventListener in interface Connection

Parameters:

listener - the listener to remove

close

public void close()
           throws java.rmi.RemoteException

Close the connection.

This closes all channels open on the connection, and then closes the underlying physical connection, prior to notifying registered ConnectionEventListener instances

Specified by:

close in interface Connection

Throws:

java.rmi.RemoteException - if an error occurs closing the connection

doClose

protected void doClose()
                throws java.rmi.RemoteException

Performs the actual connection closure, without notifying registered listeners

Throws:

java.rmi.RemoteException - if an error occurs closing the connection

getChannel

protected Channel getChannel(int channelId)

Returns the channel for the give channel identifier

Parameters:

channelId - the channel identifier

Returns:

the channel corresponding to channelId, or null, if no channel exists

getOutputQueue

protected PacketQueue getOutputQueue()

Returns the queue of packets to be streamed down the physical connection

getPool

protected org.exolab.core.messenger.PacketPool getPool()

Returns the pool of free packets

getThreadPool

protected ThreadPool getThreadPool()

Returns the thread pool

createChannel

protected PacketChannel createChannel(int channelId,
                                      int destinationId)
                               throws java.rmi.RemoteException

Throws:

java.rmi.RemoteException

closed

protected void closed(PacketChannel channel)
               throws java.rmi.RemoteException

Throws:

java.rmi.RemoteException

getNextChannelId

protected int getNextChannelId()

ensureOpen

protected void ensureOpen()
                   throws java.rmi.RemoteException

Throws:

java.rmi.RemoteException