edu.uiuc.cs.seclab.modem.xbee
Class XBeeTxnCoord

java.lang.Object
  edu.uiuc.cs.seclab.modem.xbee.XBeeTxnCoord

All Implemented Interfaces:

XBeeModemRecvListener, java.lang.Runnable

public class XBeeTxnCoord
extends java.lang.Object
implements XBeeModemRecvListener, java.lang.Runnable

Coordinates the execution of a list of AT commands. It sends messages individually and asynchronously, and then associates the responses with the appropriate command.

Nested Class Summary

protected class

XBeeTxnCoord.TxnBabysitter Thread that waits for a single transaction to complete

Field Summary

protected int	babysitterCnt
protected int	cnt
protected java.util.concurrent.BlockingQueue<XBeeTxn>	completedQ
protected java.lang.Thread	coordThread
static int	DEFL_BACKLOG
protected boolean	halted
protected XBeeModem	mdm
protected int	outstandingTxns Number of outstanding transactions tolerated by system
protected java.util.Stack<XBeeTxnCoord.TxnBabysitter>	sitters
protected java.util.concurrent.BlockingQueue<XBeeTxn>	toExec
static int	TXN_TOUT
protected XBeeTxn[]	waiting

Constructor Summary

XBeeTxnCoord(XBeeModem mdm_, int outstandingTxns_)
Create a command coordinator for a specified list of commands.

Method Summary

private void	abortTxn(XBeeTxn txn)
private void	completeTxn(XBeeTxn txn)
void	execCmd(XBeeAtCmd cmd, XBeeAtCmd.Mode mode, long toutMs) Insert a new command transaction into the queue.
void	execTxn(XBeeTxn txn, long toutMs) Insert a new transaction into the queue.
protected void	finalize()
private XBeeTxnCoord.TxnBabysitter	getBabysitter() Get/create an available transaction babysitter.
java.util.concurrent.BlockingQueue<XBeeTxn>	getCompletedQueue() Return a reference to the queue for completed transactions, so that the controlling process can synchronously process responses as they are received.
void	halt()
void	handleXBeePacket(XBeeApiPacket apiPkt)
private void	launchTxn(XBeeTxn txn)
private void	recycleBabysitter(XBeeTxnCoord.TxnBabysitter sitter)
void	run()
void	sendTx(XBeeTxPacket pkt, long toutMs) Insert a new transmission transaction into the queue.

Methods inherited from class java.lang.Object

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

Field Detail

babysitterCnt

protected int babysitterCnt

cnt

protected int cnt

completedQ

protected java.util.concurrent.BlockingQueue<XBeeTxn> completedQ

coordThread

protected java.lang.Thread coordThread

DEFL_BACKLOG

public static final int DEFL_BACKLOG

See Also:

Constant Field Values

halted

protected boolean halted

mdm

protected XBeeModem mdm

outstandingTxns

protected int outstandingTxns

Number of outstanding transactions tolerated by system

sitters

protected java.util.Stack<XBeeTxnCoord.TxnBabysitter> sitters

toExec

protected java.util.concurrent.BlockingQueue<XBeeTxn> toExec

TXN_TOUT

public static final int TXN_TOUT

See Also:

Constant Field Values

waiting

protected XBeeTxn[] waiting

Constructor Detail

XBeeTxnCoord

public XBeeTxnCoord(XBeeModem mdm_,
                    int outstandingTxns_)
             throws ModemException,
                    java.io.IOException

Create a command coordinator for a specified list of commands. Must be a linked list for efficiency.

Throws:

java.io.IOException - getBabysitter().setTxn(txn, TXN_TOUT);

ModemException

Method Detail

abortTxn

private void abortTxn(XBeeTxn txn)

completeTxn

private void completeTxn(XBeeTxn txn)

execCmd

public void execCmd(XBeeAtCmd cmd,
                    XBeeAtCmd.Mode mode,
                    long toutMs)
             throws ModemException

Insert a new command transaction into the queue. Will block if desired frame ID is still outstanding in the mode. Will block up to toutMs milliseconds, or indefinitely if toutMs == 0.

Throws:

ModemException

execTxn

public void execTxn(XBeeTxn txn,
                    long toutMs)
             throws ModemException

Insert a new transaction into the queue.

Throws:

ModemException

finalize

protected void finalize()
                 throws java.lang.Throwable

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable

getBabysitter

private XBeeTxnCoord.TxnBabysitter getBabysitter()

Get/create an available transaction babysitter.

getCompletedQueue

public java.util.concurrent.BlockingQueue<XBeeTxn> getCompletedQueue()

Return a reference to the queue for completed transactions, so that the controlling process can synchronously process responses as they are received. Also returns aborted transactions, so it's important to manually verify that transactions have actually completed.

halt

public void halt()

handleXBeePacket

public void handleXBeePacket(XBeeApiPacket apiPkt)

Specified by:

handleXBeePacket in interface XBeeModemRecvListener

launchTxn

private void launchTxn(XBeeTxn txn)
                throws ModemException,
                       java.io.IOException

Throws:

ModemException

java.io.IOException

recycleBabysitter

private void recycleBabysitter(XBeeTxnCoord.TxnBabysitter sitter)

run

public void run()

Specified by:

run in interface java.lang.Runnable

sendTx

public void sendTx(XBeeTxPacket pkt,
                   long toutMs)
            throws ModemException

Insert a new transmission transaction into the queue.

Throws:

ModemException