org.springframework.integration.ip.udp
Class UnicastSendingMessageHandler

java.lang.Object
  org.springframework.integration.ip.AbstractInternetProtocolSendingMessageHandler
      org.springframework.integration.ip.udp.UnicastSendingMessageHandler

All Implemented Interfaces:

java.lang.Runnable, CommonSocketOptions, MessageHandler

Direct Known Subclasses:

MulticastSendingMessageHandler

public class UnicastSendingMessageHandler
extends AbstractInternetProtocolSendingMessageHandler
implements java.lang.Runnable

A MessageHandler implementation that maps a Message into a UDP datagram packet and sends that to the specified host and port. Messages can be basic, with no support for reliability, can be prefixed by a length so the receiving end can detect truncation, and can require a UDP acknowledgment to confirm delivery.

Since:

2.0

Author:

Gary Russell

Field Summary

protected java.util.Map<java.lang.String,java.util.concurrent.CountDownLatch>	ackControl
protected int	ackCounter
protected int	ackPort
protected java.net.DatagramSocket	ackSocket
protected int	ackTimeout
protected java.lang.Exception	fatalException
protected DatagramPacketMessageMapper	mapper
protected java.net.DatagramSocket	socket
protected int	soReceiveBufferSize
protected boolean	waitForAck If true adds headers to instruct receiving adapter to return an ack.

Fields inherited from class org.springframework.integration.ip.AbstractInternetProtocolSendingMessageHandler

destinationAddress, executorService, host, logger, port, soSendBufferSize, soTimeout

Constructor Summary

UnicastSendingMessageHandler(java.lang.String host, int port)
Basic constructor; no reliability; no acknowledgment.

UnicastSendingMessageHandler(java.lang.String host, int port, boolean lengthCheck)
Can used to add a length to each packet which can be checked at the destination.

UnicastSendingMessageHandler(java.lang.String host, int port, boolean lengthCheck, boolean acknowledge, java.lang.String ackHost, int ackPort, int ackTimeout)
Add a length and/or acknowledgment request to packets.

UnicastSendingMessageHandler(java.lang.String host, int port, boolean acknowledge, java.lang.String ackHost, int ackPort, int ackTimeout)
Add an acknowledgment request to packets.

Method Summary

protected java.net.DatagramSocket	getSocket()
void	handleMessage(Message<?> message) Handles the message if possible.
void	restartAckThread() If exposed as an MBean, can be used to restart the ack thread if a fatal (bind) error occurred, without bouncing the JVM.
void	run() Process acknowledgments, if requested.
protected void	send(java.net.DatagramPacket packet)
protected void	setReliabilityAttributes(boolean lengthCheck, boolean acknowledge, java.lang.String ackHost, int ackPort, int ackTimeout)
protected void	setSocketAttributes(java.net.DatagramSocket socket)
void	setSoReceiveBufferSize(int size)
void	shutDown()

Methods inherited from class org.springframework.integration.ip.AbstractInternetProtocolSendingMessageHandler

getPort, setSoSendBufferSize, setSoTimeout

Methods inherited from class java.lang.Object

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

Field Detail

mapper

protected final DatagramPacketMessageMapper mapper

socket

protected volatile java.net.DatagramSocket socket

waitForAck

protected volatile boolean waitForAck

If true adds headers to instruct receiving adapter to return an ack.

ackPort

protected volatile int ackPort

ackTimeout

protected volatile int ackTimeout

ackCounter

protected volatile int ackCounter

ackControl

protected volatile java.util.Map<java.lang.String,java.util.concurrent.CountDownLatch> ackControl

ackSocket

protected volatile java.net.DatagramSocket ackSocket

fatalException

protected volatile java.lang.Exception fatalException

soReceiveBufferSize

protected int soReceiveBufferSize

Constructor Detail

UnicastSendingMessageHandler

public UnicastSendingMessageHandler(java.lang.String host,
                                    int port)

Basic constructor; no reliability; no acknowledgment.

Parameters:

host - Destination host.

port - Destination port.

UnicastSendingMessageHandler

public UnicastSendingMessageHandler(java.lang.String host,
                                    int port,
                                    boolean lengthCheck)

Can used to add a length to each packet which can be checked at the destination.

Parameters:

host - Destination Host.

port - Destination Port.

lengthCheck - If true, packets will contain a length.

UnicastSendingMessageHandler

public UnicastSendingMessageHandler(java.lang.String host,
                                    int port,
                                    boolean acknowledge,
                                    java.lang.String ackHost,
                                    int ackPort,
                                    int ackTimeout)

Add an acknowledgment request to packets.

Parameters:

host - Destination Host.

port - Destination Port.

acknowledge - If true, packets will request acknowledgment.

ackHost - The host to which acks should be sent. Required if ack true.

ackPort - The port to which acks should be sent.

ackTimeout - How long we will wait (milliseconds) for the ack.

UnicastSendingMessageHandler

public UnicastSendingMessageHandler(java.lang.String host,
                                    int port,
                                    boolean lengthCheck,
                                    boolean acknowledge,
                                    java.lang.String ackHost,
                                    int ackPort,
                                    int ackTimeout)

Add a length and/or acknowledgment request to packets.

Parameters:

host - Destination Host.

port - Destination Port.

lengthCheck - If true, packets will contain a length.

acknowledge - If true, packets will request acknowledgment.

ackHost - The host to which acks should be sent. Required if ack true.

ackPort - The port to which acks should be sent.

ackTimeout - How long we will wait (milliseconds) for the ack.

Method Detail

setReliabilityAttributes

protected void setReliabilityAttributes(boolean lengthCheck,
                                        boolean acknowledge,
                                        java.lang.String ackHost,
                                        int ackPort,
                                        int ackTimeout)

handleMessage

public void handleMessage(Message<?> message)
                   throws MessageRejectedException,
                          MessageHandlingException,
                          MessageDeliveryException

Description copied from interface: MessageHandler

Handles the message if possible. If the handler cannot deal with the message this will result in a MessageRejectedException e.g. in case of a Selective Consumer. When a consumer tries to handle a message, but fails to do so, a MessageHandlingException is thrown. In the last case it is recommended to treat the message as tainted and go into an error scenario.

When the handling results in a message being sent failure to send that message will result in a MessageDeliveryException.

Specified by:

handleMessage in interface MessageHandler

Parameters:

message - the message to be handled

Throws:

MessageRejectedException - if the handler doesn't select these types of messages

MessageHandlingException - when something went wrong during the handling

MessageDeliveryException - when this handler failed to deliver the reply related to the handling of the message

send

protected void send(java.net.DatagramPacket packet)
             throws java.lang.Exception

Throws:

java.lang.Exception

getSocket

protected java.net.DatagramSocket getSocket()
                                     throws java.io.IOException

Throws:

java.io.IOException

setSocketAttributes

protected void setSocketAttributes(java.net.DatagramSocket socket)
                            throws java.net.SocketException

Throws:

java.net.SocketException

run

public void run()

Process acknowledgments, if requested.

Specified by:

run in interface java.lang.Runnable

restartAckThread

public void restartAckThread()

If exposed as an MBean, can be used to restart the ack thread if a fatal (bind) error occurred, without bouncing the JVM.

shutDown

public void shutDown()

setSoReceiveBufferSize

public void setSoReceiveBufferSize(int size)

Specified by:

setSoReceiveBufferSize in interface CommonSocketOptions

Overrides:

setSoReceiveBufferSize in class AbstractInternetProtocolSendingMessageHandler

Parameters:

size -

See Also:

Socket#setReceiveBufferSize(int)} and {@link DatagramSocket#setReceiveBufferSize(int)}