edu.jas.util

Class DistThreadPool

java.lang.Object

edu.jas.util.DistThreadPool

public class DistThreadPool
extends java.lang.Object

Distributed thread pool. Using stack / list work-pile and Executable Channels and Servers.

Author:

Heinz Kredel

Field Summary

Fields

Modifier and Type	Field and Description
protected int	idleworkers Number of idle workers.
protected java.util.LinkedList<java.lang.Runnable>	jobstack Work queue / stack.
protected StrategyEnumeration	strategy
protected int	threads Number of threads to use.
protected edu.jas.util.DistPoolThread[]	workers Array of workers.

Constructor Summary

Constructors

Constructor and Description
DistThreadPool() Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO and size DEFAULT_SIZE.
DistThreadPool(int size) Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO.
DistThreadPool(int size, java.lang.String mfile) Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO.
DistThreadPool(StrategyEnumeration strategy) Constructs a new DistThreadPool with size DEFAULT_SIZE.
DistThreadPool(StrategyEnumeration strategy, int size, java.lang.String mfile) Constructs a new DistThreadPool.

Method Summary

Methods

Modifier and Type	Method and Description
void	addJob(java.lang.Runnable job) adds a job to the workpile.
ExecutableChannels	getEC() the used executable channel.
protected java.lang.Runnable	getJob() get a job for processing.
int	getNumber() number of worker threads.
StrategyEnumeration	getStrategy() get used strategy.
boolean	hasJobs() check if there are jobs for processing.
boolean	hasJobs(int n) check if there are more than n jobs for processing.
void	init() thread initialization and start.
void	terminate() Terminates the threads.
void	terminate(boolean shutDown) Terminates the threads.
java.lang.String	toString() String representation.

Methods inherited from class java.lang.Object

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

Field Detail

threads

protected final int threads

Number of threads to use.

workers

protected edu.jas.util.DistPoolThread[] workers

Array of workers.

idleworkers

protected int idleworkers

Number of idle workers.

jobstack

protected java.util.LinkedList<java.lang.Runnable> jobstack

Work queue / stack.

strategy

protected StrategyEnumeration strategy

Constructor Detail

DistThreadPool

public DistThreadPool()

Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO and size DEFAULT_SIZE.

DistThreadPool

public DistThreadPool(StrategyEnumeration strategy)

Constructs a new DistThreadPool with size DEFAULT_SIZE.

Parameters:

strategy - for job processing.

DistThreadPool

public DistThreadPool(int size)

Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO.

Parameters:

size - of the pool.

DistThreadPool

public DistThreadPool(int size,
              java.lang.String mfile)

Constructs a new DistThreadPool with strategy StrategyEnumeration.FIFO.

Parameters:

size - of the pool.

mfile - machine file.

DistThreadPool

public DistThreadPool(StrategyEnumeration strategy,
              int size,
              java.lang.String mfile)

Constructs a new DistThreadPool.

Parameters:

strategy - for job processing.

size - of the pool.

mfile - machine file.

Method Detail

toString

public java.lang.String toString()

String representation.

Overrides:

toString in class java.lang.Object

init

public void init()

thread initialization and start.

getNumber

public int getNumber()

number of worker threads.

getStrategy

public StrategyEnumeration getStrategy()

get used strategy.

getEC

public ExecutableChannels getEC()

the used executable channel.

terminate

public void terminate(boolean shutDown)

Terminates the threads.

Parameters:

shutDown - true, if shut-down of the remote executable servers is requested, false, if remote executable servers stay alive.

terminate

public void terminate()

Terminates the threads.

addJob

public void addJob(java.lang.Runnable job)

adds a job to the workpile.

Parameters:

job -

getJob

protected java.lang.Runnable getJob()
                             throws java.lang.InterruptedException

get a job for processing.

Throws:

java.lang.InterruptedException

hasJobs

public boolean hasJobs()

check if there are jobs for processing.

hasJobs

public boolean hasJobs(int n)

check if there are more than n jobs for processing.

Parameters:

n - Integer

Returns:

true, if there are possibly more than n jobs.