edu.nps.moves.disutil
Interface NioServer.Listener

All Superinterfaces:

java.util.EventListener

All Known Implementing Classes:

NioServer.Adapter

Enclosing class:

NioServer

public static interface NioServer.Listener
extends java.util.EventListener

An interface for listening to events from a NioServer. A single NioServer.Event is shared for all invocations of these methods.

This code is released into the Public Domain. Since this is Public Domain, you don't need to worry about licensing, and you can simply copy this NioServer.java file to your own package and use it as you like. Enjoy. Please consider leaving the following statement here in this code:

This NioServer class was copied to this project from its source as found at iHarder.net.

Version:

0.1

Author:

Robert Harder, rharder@users.sourceforge.net

See Also:

NioServer, NioServer.Adapter, NioServer.Event

Method Summary

void	nioServerConnectionClosed(NioServer.Event evt) Called when a connection is closed remotely.
void	nioServerNewConnectionReceived(NioServer.Event evt) Called when a new connection is received.
void	nioServerTcpDataReceived(NioServer.Event evt) Called when TCP data is received.
void	nioServerUdpDataReceived(NioServer.Event evt) Called when UDP data is received.

Method Detail

nioServerNewConnectionReceived

void nioServerNewConnectionReceived(NioServer.Event evt)

Called when a new connection is received. The SelectionKey associated with the event (an OP_READ key), is the key that will be used with the data received event. In this way, you can seed a Map or other data structure and associate this very key with the connection. You will only get new connection events for TCP connections (not UDP).

The key's attachment mechanism is unused by NioServer and is available for you to store whatever you like.

If your protocol requires the server to respond to a client upon connection, this sample code demonstrates such an arrangement:

   public void nioServerNewConnectionReceived(NioServer.Event evt) {
       SocketChannel ch = (SocketChannel) evt.getKey().channel();
       try {
           ch.write(ByteBuffer.wrap("Greetings\r\n".getBytes()));
       } catch (IOException ex) {
           ex.printStackTrace(); // Please don't do printStackTrace in production code
       }
   }
 

Parameters:

evt - the shared event

nioServerTcpDataReceived

void nioServerTcpDataReceived(NioServer.Event evt)

Called when TCP data is received. Retrieve the associated ByteBuffer with evt.getBuffer(). This is the source ByteBuffer used by the server directly to receive the data. It is a "direct" ByteBuffer (created with ByteBuffer.allocateDirect(..)). Read from it as much as you can. Any data that remains on or after the value of position() will be saved for the next time an event is fired. In this way, you can defer processing incomplete data until everything arrives. Be careful that you don't leave the buffer full or you won't be able to receive anything next time around (unless you call NioServer.setBufferSize(int) to resize buffer).

The key's attachment mechanism is unused by NioServer and is available for you to store whatever you like.

Example: You are receiving lines of text. The ByteBuffer returned here contains one and a half lines of text. When you realize this, you process the first line as you like, but you leave this buffer's position at the beginning of the second line. In this way, The beginning of the second line will be the start of the buffer the next time around.

Parameters:

evt - the shared event

nioServerUdpDataReceived

void nioServerUdpDataReceived(NioServer.Event evt)

Called when UDP data is received. Retrieve the associated ByteBuffer with evt.getBuffer(). This is the source ByteBuffer used by the server directly to receive the data. It is a "direct" ByteBuffer (created with ByteBuffer.allocateDirect(..)). The contents of the ByteBuffer will be the entire contents received from the UDP datagram.

Parameters:

evt - the shared event

nioServerConnectionClosed

void nioServerConnectionClosed(NioServer.Event evt)

Called when a connection is closed remotely. If you close the connection somewhere in your own code, this event probably won't be fired.

Parameters:

evt - the shared event