Package jmri.jmrix.dcc4pc

Class Dcc4PcTrafficController

java.lang.Object

jmri.jmrix.AbstractMRTrafficController

jmri.jmrix.dcc4pc.Dcc4PcTrafficController

All Implemented Interfaces:

Dcc4PcInterface

public class Dcc4PcTrafficController
extends AbstractMRTrafficController
implements Dcc4PcInterface

Converts Stream-based I/O to/from DCC4PC messages. The "Dcc4PcInterface" side sends/receives message objects.

The connection to a Dcc4PcPortController is via a pair of *Streams, which then carry sequences of characters for transmission. Note that this processing is handled in an independent thread.

This handles the state transitions, based on the necessary state in each message.

Nested Class Summary

Nested classes/interfaces inherited from class jmri.jmrix.AbstractMRTrafficController

AbstractMRTrafficController.RcvNotifier, AbstractMRTrafficController.XmtNotifier

Field Summary

Fields

Modifier and Type	Field	Description
(package private) Dcc4PcSystemConnectionMemo	adaptermemo
(package private) final int	GETMOREDATA
(package private) Dcc4PcReply	lastIncomplete
(package private) long	lastTransactionEnd
(package private) boolean	loading
(package private) static final long	MAX_REOPEN_DELAY	Longest wait between attempts to reopen a port that is listed but won't open.
(package private) static final int	MAX_SEQUENCE_TIME	Longest a single reply sequence may hold up the transmit thread.
(package private) static final int	MIN_GAP_MS	Quiet time between the end of one transaction and the start of the next.
(package private) Dcc4PcMessage	mLastMessage
(package private) Dcc4PcMessage	mLastSentMessage
(package private) boolean	normalFlushReceiveChars
(package private) SerialPort	port
(package private) boolean	readingData
(package private) boolean	recovering	True from a port failure until the port has been reopened.
(package private) long	recoveryPollMillis	How often to check whether the port is back.
static final int	RETRIEVINGDATA
(package private) boolean	sequenceInProgress
(package private) static final long	STUCK_WRITE_MILLIS	A write that hasn't finished after this long means the USB link has jammed.
protected boolean	unsolicitedSensorMessageSeen
(package private) boolean	waitingForMore

Fields inherited from class jmri.jmrix.AbstractMRTrafficController

allowUnexpectedReply, AUTORETRYSTATE, cmdListeners, connectionError, controller, flushReceiveChars, IDLESTATE, istream, listenerQueue, maxRcvExceptionCount, mCurrentMode, mCurrentState, mLastSender, msgQueue, mWaitBeforePoll, NORMALMODE, NOTIFIEDSTATE, OKSENDMSGSTATE, ostream, POLLSTATE, PROGRAMINGMODE, rcvException, rcvThread, replyInDispatch, threadStopRequest, timeoutFlag, timeouts, WAITMSGREPLYSTATE, WAITREPLYINNORMMODESTATE, WAITREPLYINPROGMODESTATE, waitTimePoll, xmtException, xmtRunnable, xmtThread

Constructor Summary

Constructors

Constructor	Description
Dcc4PcTrafficController()	Create a new DccPcTrafficController instance.

Method Summary

Modifier and Type	Method	Description
void	addDcc4PcListener(Dcc4PcListener l)
protected void	addTrailerToOutput(byte[] msg, int offset, AbstractMRMessage m)	Add trailer to the outgoing byte stream.
protected boolean	canReceive()	Override in the system specific code if necessary
void	connectPort(AbstractPortController p)	Make connection to an existing PortController object.
protected boolean	endOfMessage(AbstractMRReply msg)
protected AbstractMRMessage	enterNormalMode()	Sets the system to normal mode during programming while in IDLESTATE.
protected AbstractMRMessage	enterProgMode()	Set the system to programming mode.
protected void	forwardMessage(AbstractMRListener client, AbstractMRMessage m)	Forward a Dcc4PcMessage to all registered Dcc4PcInterface listeners.
protected void	forwardReply(AbstractMRListener client, AbstractMRReply r)	Forward a Dcc4PcReply to all registered Dcc4PcInterface listeners.
protected void	forwardToPort(AbstractMRMessage m, AbstractMRListener reply)	Actually transmit the next message to the port.
void	handleOneIncomingReply()	Handle each reply when complete.
protected void	handleTimeout(AbstractMRMessage msg, AbstractMRListener l)
protected void	loadChars(AbstractMRReply msg, DataInputStream istream)	Get characters from the input source, and file a message.
protected AbstractMRReply	newReply()
protected AbstractMRMessage	pollMessage()	Invoked if it's appropriate to do low-priority polling of the command station, this should return the next message to send, or null if the TrafficController should just sleep.
protected AbstractMRListener	pollReplyHandler()
void	receiveLoop()	Like the base class's loop, but a failed port doesn't end it: the port is reopened (see portFailed(java.lang.String)) and reading carries on.
void	removeDcc4PcListener(Dcc4PcListener l)
void	sendDcc4PcMessage(Dcc4PcMessage m, Dcc4PcListener reply)	Forward a preformatted message to the actual interface.
void	setAdapterMemo(Dcc4PcSystemConnectionMemo memo)
void	setReconnectHandler(Runnable handler)
protected void	terminate()	At shutdown, put every board and the interface back to 8 kbps so other programs can talk to them.
void	terminateThreads()	Terminate the receive and transmit threads.
protected void	transmitWait(int waitTime, int state, String InterruptMessage)

Methods inherited from class jmri.jmrix.AbstractMRTrafficController

addConsoleListener, addHeaderToOutput, addListener, connectionWarn, disconnectPort, distributeReply, enterProgModeDelayTime, getLastSender, getPortName, getSynchronizeRx, hasTimeouts, isAtRest, lengthOfByteStream, newRcvNotifier, notifyMessage, notifyReply, portReadyToSend, portWarn, portWarnTCP, programmerIdle, readByteProtected, recovery, removeListener, reportReceiveLoopException, resetTimeout, sendMessage, setAllowUnexpectedReply, setSynchronizeRx, status, transmitLoop, unexpectedReplyStateError, waitForStartOfReply, warnOnTimeout

Methods inherited from class java.lang.Object

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

Methods inherited from interface jmri.jmrix.dcc4pc.Dcc4PcInterface

status

Field Details

adaptermemo

Dcc4PcSystemConnectionMemo adaptermemo

RETRIEVINGDATA

public static final int RETRIEVINGDATA

See Also:

• Constant Field Values

unsolicitedSensorMessageSeen

protected boolean unsolicitedSensorMessageSeen

STUCK_WRITE_MILLIS

static final long STUCK_WRITE_MILLIS

A write that hasn't finished after this long means the USB link has jammed.

See Also:

• Constant Field Values

recovering

volatile boolean recovering

True from a port failure until the port has been reopened.

recoveryPollMillis

long recoveryPollMillis

How often to check whether the port is back.

MAX_REOPEN_DELAY

static final long MAX_REOPEN_DELAY

Longest wait between attempts to reopen a port that is listed but won't open.

See Also:

• Constant Field Values

mLastMessage

Dcc4PcMessage mLastMessage

mLastSentMessage

Dcc4PcMessage mLastSentMessage

MIN_GAP_MS

static final int MIN_GAP_MS

Quiet time between the end of one transaction and the start of the next. Sending each Get Response straight after the last reply ended jammed the interface's USB link after a few minutes of polling with two locos; our standalone tools always leave about this long, and ran for minutes without a jam.

See Also:

• Constant Field Values

lastTransactionEnd

volatile long lastTransactionEnd

port

volatile SerialPort port

lastIncomplete

Dcc4PcReply lastIncomplete

waitingForMore

boolean waitingForMore

loading

boolean loading

sequenceInProgress

volatile boolean sequenceInProgress

MAX_SEQUENCE_TIME

static final int MAX_SEQUENCE_TIME

Longest a single reply sequence may hold up the transmit thread.

See Also:

• Constant Field Values

GETMOREDATA

final int GETMOREDATA

See Also:

• Constant Field Values

normalFlushReceiveChars

boolean normalFlushReceiveChars

readingData

boolean readingData

Constructor Details

Dcc4PcTrafficController

public Dcc4PcTrafficController()

Create a new DccPcTrafficController instance.

Method Details

setAdapterMemo

public void setAdapterMemo(Dcc4PcSystemConnectionMemo memo)

addDcc4PcListener

public void addDcc4PcListener(Dcc4PcListener l)

Specified by:

addDcc4PcListener in interface Dcc4PcInterface

removeDcc4PcListener

public void removeDcc4PcListener(Dcc4PcListener l)

Specified by:

removeDcc4PcListener in interface Dcc4PcInterface

forwardMessage

protected void forwardMessage(AbstractMRListener client,
 AbstractMRMessage m)

Forward a Dcc4PcMessage to all registered Dcc4PcInterface listeners.

Specified by:

forwardMessage in class AbstractMRTrafficController

Parameters:

client - abstract listener.

m - message to forward.

forwardReply

protected void forwardReply(AbstractMRListener client,
 AbstractMRReply r)

Forward a Dcc4PcReply to all registered Dcc4PcInterface listeners.

Specified by:

forwardReply in class AbstractMRTrafficController

pollMessage

protected AbstractMRMessage pollMessage()

Description copied from class: AbstractMRTrafficController

Invoked if it's appropriate to do low-priority polling of the command station, this should return the next message to send, or null if the TrafficController should just sleep.

Specified by:

pollMessage in class AbstractMRTrafficController

Returns:

Formatted poll message

pollReplyHandler

protected AbstractMRListener pollReplyHandler()

Specified by:

pollReplyHandler in class AbstractMRTrafficController

sendDcc4PcMessage

public void sendDcc4PcMessage(Dcc4PcMessage m,
 Dcc4PcListener reply)

Forward a preformatted message to the actual interface.

Specified by:

sendDcc4PcMessage in interface Dcc4PcInterface

Parameters:

m - Message to be sent.

reply - Listener to be notified of reply.

enterProgMode

protected AbstractMRMessage enterProgMode()

Description copied from class: AbstractMRTrafficController

Set the system to programming mode.

Specified by:

enterProgMode in class AbstractMRTrafficController

Returns:

any message that needs to be returned to the Command Station to change modes. If no message is needed, returns null.

See Also:

• AbstractMRTrafficController.enterNormalMode()

enterNormalMode

protected AbstractMRMessage enterNormalMode()

Description copied from class: AbstractMRTrafficController

Sets the system to normal mode during programming while in IDLESTATE. If AbstractMRTrafficController.programmerIdle() returns true, enterNormalMode() is called after a timeout.

Specified by:

enterNormalMode in class AbstractMRTrafficController

Returns:

any message that needs to be returned to the Command Station to change modes. If no message is needed, returns null.

See Also:

• AbstractMRTrafficController.enterProgMode()

terminate

protected void terminate()

At shutdown, put every board and the interface back to 8 kbps so other programs can talk to them. The next JMRI start resets the speed anyway.

Overrides:

terminate in class AbstractMRTrafficController

terminateThreads

public void terminateThreads()

Terminate the receive and transmit threads.

This is intended to be used only by testing subclasses.

Overrides:

terminateThreads in class AbstractMRTrafficController

setReconnectHandler

public void setReconnectHandler(Runnable handler)

addTrailerToOutput

protected void addTrailerToOutput(byte[] msg,
 int offset,
 AbstractMRMessage m)

Description copied from class: AbstractMRTrafficController

Add trailer to the outgoing byte stream.

Overrides:

addTrailerToOutput in class AbstractMRTrafficController

Parameters:

msg - the output byte stream

offset - the first byte not yet used

m - output message to extend

forwardToPort

protected void forwardToPort(AbstractMRMessage m,
 AbstractMRListener reply)

Description copied from class: AbstractMRTrafficController

Actually transmit the next message to the port.

Overrides:

forwardToPort in class AbstractMRTrafficController

Parameters:

m - the message to send

reply - the Listener sending the message, often provided as 'this'

See Also:

• AbstractMRTrafficController.sendMessage(AbstractMRMessage, AbstractMRListener)

connectPort

public void connectPort(AbstractPortController p)

Description copied from class: AbstractMRTrafficController

Make connection to an existing PortController object.

Overrides:

connectPort in class AbstractMRTrafficController

Parameters:

p - the PortController

receiveLoop

public void receiveLoop()

Like the base class's loop, but a failed port doesn't end it: the port is reopened (see portFailed(java.lang.String)) and reading carries on.

Overrides:

receiveLoop in class AbstractMRTrafficController

newReply

protected AbstractMRReply newReply()

Specified by:

newReply in class AbstractMRTrafficController

canReceive

protected boolean canReceive()

Description copied from class: AbstractMRTrafficController

Override in the system specific code if necessary

Overrides:

canReceive in class AbstractMRTrafficController

Returns:

true if it is okay to buffer receive characters into a reply message. When false, discard char received

endOfMessage

protected boolean endOfMessage(AbstractMRReply msg)

Specified by:

endOfMessage in class AbstractMRTrafficController

handleTimeout

protected void handleTimeout(AbstractMRMessage msg,
 AbstractMRListener l)

Overrides:

handleTimeout in class AbstractMRTrafficController

handleOneIncomingReply

public void handleOneIncomingReply()
                            throws IOException

Handle each reply when complete.

(This is public for testing purposes) Runs in the "Receive" thread.

Overrides:

handleOneIncomingReply in class AbstractMRTrafficController

Throws:

IOException - on error.

loadChars

protected void loadChars(AbstractMRReply msg,
 DataInputStream istream)
                  throws IOException

Description copied from class: AbstractMRTrafficController

Get characters from the input source, and file a message.

Returns only when the message is complete.

Only used in the Receive thread.

Handles timeouts on read by ignoring zero-length reads.

Overrides:

loadChars in class AbstractMRTrafficController

Parameters:

msg - message to fill

istream - character source.

Throws:

IOException - when presented by the input source.

transmitWait

protected void transmitWait(int waitTime,
 int state,
 String InterruptMessage)

Overrides:

transmitWait in class AbstractMRTrafficController