jarol.messages
Class UDPLink

java.lang.Object
  jarol.messages.Link
      jarol.messages.UDPLink

public class UDPLink
extends Link

UDP socket message link.

This message link allows simple bi-directional communication between UDP ports. The local host will listen on a specified local port for messages and send messages to a specified UDP port on a remote host.

Version:

0.1

Author:

Eduardo Marques

Field Summary

Fields inherited from class jarol.messages.Link

DEFAULT_PORT_BUFSZ, MAX_MESSAGE_PAYLOAD

Constructor Summary

UDPLink(MessageFactory factory, java.lang.String host, int localPort, int remotePort)
Constructor.

UDPLink(MessageFactory factory, java.lang.String host, int localPort, int remotePort, int recvBufSz, int sendBufSz)
Constructor with specified receive / send buffer size.

Method Summary

protected int	recv(byte[] buf, int off, int len, int timeout) Receive data.
protected void	send(byte[] data, int off, int len) Send data to the remote UDP socket.
protected void	start() Start the UDP link.
protected void	stop() Stop the UDP link.

Methods inherited from class jarol.messages.Link

connect, connected, disconnect, getRecvPort, getSendPort, getSendSignal

Methods inherited from class java.lang.Object

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

Constructor Detail

UDPLink

public UDPLink(MessageFactory factory,
               java.lang.String host,
               int localPort,
               int remotePort)
        throws java.net.UnknownHostException

Constructor. Note that this only initializes the UDP link, but does not start it. This is done through the connect() method in the parent MessageLink class.

Parameters:

factory - the message factory to use

host - host name or IP address

localPort - local UDP port

remotePort - remote UDP port

Throws:

java.net.UnknownHostException - as described in InetAddress.getByName()

UDPLink

public UDPLink(MessageFactory factory,
               java.lang.String host,
               int localPort,
               int remotePort,
               int recvBufSz,
               int sendBufSz)
        throws java.net.UnknownHostException

Constructor with specified receive / send buffer size. Note that this only initializes the UDP link, but does not start it. This is done through the connect() method in the parent MessageLink class.

Parameters:

factory - the message factory to use

host - host name or IP address

localPort - local UDP port

remotePort - remote UDP port

recvBufSz - receive buffer size

sendBufSz - send buffer size

Throws:

java.net.UnknownHostException - as described in InetAddress.getByName()

Method Detail

start

protected void start()
              throws java.io.IOException

Start the UDP link.

This will set up the UDP datagram socket listening onto the local UDP port.

Specified by:

start in class Link

Throws:

java.io.IOException - if an error occurs creating the socket.

stop

protected void stop()
             throws java.io.IOException

Stop the UDP link.

This will close the UDP datagram socket.

Specified by:

stop in class Link

Throws:

java.io.IOException - if an error occurs closing the socket.

recv

protected int recv(byte[] buf,
                   int off,
                   int len,
                   int timeout)
            throws java.io.IOException

Receive data.

Specified by:

recv in class Link

Parameters:

buf - read buffer

off - read buffer offset

len - read buffer usable length

timeout - timeout for receive

Returns:

the next datagram packet's payload length or 0 if timeout has been reached

Throws:

java.io.IOException - if a network error occurs

send

protected void send(byte[] data,
                    int off,
                    int len)
             throws java.io.IOException

Send data to the remote UDP socket.

Specified by:

send in class Link

Parameters:

data - data buffer

off - data buffer offset

len - data buffer usable length

Throws:

java.io.IOException - if a network error occurs