ec.eval

Class SlaveConnection

java.lang.Object

ec.eval.SlaveConnection

 class SlaveConnection
extends Object

SlaveConnection.java This class contains certain information associated with a slave: its name, connection socket, input and output streams, and the job queue. Additionally, the class sets up an auxillary thread which reads and writes to the streams to talk to the slave in the background. This thread uses the SlaveMonitor as its synchronization point (it sleeps with wait() and wakes up when notified() to do some work).

Generally SlaveConnection is only seen by communicates only with SlaveMonitor.

Version:

2.0

Author:

Liviu Panait, Keith Sullivan, and Sean Luke

Field Summary

Fields

Modifier and Type	Field and Description
DataInputStream	dataIn Used to read results and randoms state from slave.
(package private) DataOutputStream	dataOut Used to transmit data to the slave.
(package private) Socket	evalSocket Socket for communication with the slave process
(package private) LinkedList	jobs
(package private) ThreadPool.Worker	reader
(package private) Runnable	readerRun
(package private) boolean	showDebugInfo
(package private) Object	shutDownLock
(package private) boolean	shuttingDown This method is called whenever there are any communication problems with the slave (indicating possibly that the slave might have crashed).
(package private) SlaveMonitor	slaveMonitor
(package private) String	slaveName Name of the slave process
(package private) EvolutionState	state
(package private) ThreadPool.Worker	writer
(package private) Runnable	writerRun

Constructor Summary

Constructors

Constructor and Description
SlaveConnection(EvolutionState state, String slaveName, Socket evalSocket, DataOutputStream dataOut, DataInputStream dataIn, SlaveMonitor slaveMonitor) The constructor also creates the queue storing the jobs that the slave has been asked to evaluate.

Method Summary

Methods

Modifier and Type	Method and Description
(package private) void	buildThreads()
(package private) void	debug(String s)
int	numJobs() Returns the number of jobs that a slave is in charge of.
(package private) Job	oldestUnsentJob()
(package private) boolean	readLoop()
(package private) void	rescheduleJobs(EvolutionState state) Reschedules the jobs in this job queue to other slaves in the system.
void	scheduleJob(Job job) Adds a new jobs to the queue.
protected void	shutdown(EvolutionState state)
String	toString()
(package private) boolean	writeLoop()

Methods inherited from class java.lang.Object

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

Field Detail

slaveName

String slaveName

Name of the slave process

evalSocket

Socket evalSocket

Socket for communication with the slave process

dataOut

DataOutputStream dataOut

Used to transmit data to the slave.

dataIn

public DataInputStream dataIn

Used to read results and randoms state from slave.

state

EvolutionState state

slaveMonitor

SlaveMonitor slaveMonitor

reader

ThreadPool.Worker reader

readerRun

Runnable readerRun

writer

ThreadPool.Worker writer

writerRun

Runnable writerRun

jobs

LinkedList jobs

shuttingDown

boolean shuttingDown

This method is called whenever there are any communication problems with the slave (indicating possibly that the slave might have crashed). In this case, the jobs will be rescheduled for evaluation on other slaves.

shutDownLock

Object shutDownLock

showDebugInfo

boolean showDebugInfo

Constructor Detail

SlaveConnection

public SlaveConnection(EvolutionState state,
               String slaveName,
               Socket evalSocket,
               DataOutputStream dataOut,
               DataInputStream dataIn,
               SlaveMonitor slaveMonitor)

The constructor also creates the queue storing the jobs that the slave has been asked to evaluate. It also creates and launches the worker thread that is communicating with the remote slave to read back the results of the evaluations.

Method Detail

shutdown

protected void shutdown(EvolutionState state)

toString

public String toString()

Overrides:

toString in class Object

debug

final void debug(String s)

numJobs

public int numJobs()

Returns the number of jobs that a slave is in charge of.

buildThreads

void buildThreads()

oldestUnsentJob

Job oldestUnsentJob()

writeLoop

boolean writeLoop()

readLoop

boolean readLoop()

scheduleJob

public void scheduleJob(Job job)

Adds a new jobs to the queue. This implies that the slave will be in charge of executing this particular job.

rescheduleJobs

void rescheduleJobs(EvolutionState state)

Reschedules the jobs in this job queue to other slaves in the system. It assumes that the slave associated with this queue has already been removed from the available slaves, such that it is not assigned its own jobs.