org.apache.excalibur.thread.impl

Class WorkerThread

java.lang.Object

java.lang.Thread

org.apache.excalibur.thread.impl.WorkerThread

All Implemented Interfaces:

java.lang.Runnable

Direct Known Subclasses:

SimpleWorkerThread

public class WorkerThread
extends java.lang.Thread

This class extends the Thread class to add recyclable functionalities.

Author:

Avalon Development Team

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields

Modifier and Type	Field and Description
private static boolean	ENABLE_DEBUG Enables debug output of major events.
private static boolean	ENABLE_DETAIL_DEBUG Enables debug output of minor events.
private boolean	m_alive True if this thread is alive and not scheduled for shutdown.
private boolean	m_clearInterruptFlag True if this thread needs to clear the interrupt flag
private AbstractThreadPool	m_pool The thread pool this thread is associated with.
private DefaultThreadControl	m_threadControl The thread control associated with current work.
private org.apache.excalibur.thread.Executable	m_work The work currentlyy associated with worker (May be null).

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	WorkerThread(AbstractThreadPool pool, java.lang.ThreadGroup group, java.lang.String name) Allocates a new Worker object.

Method Summary

Methods

Modifier and Type	Method and Description
void	clearInterruptFlag() Clears the interrupt flag for this thread.
protected void	debug(java.lang.String message) Used to log major events against the worker.
protected void	debug(java.lang.String message, java.lang.Throwable throwable) Used to log major events against the worker.
protected void	detailDebug(java.lang.String message) Used to log minor events against the worker.
protected void	detailDebug(java.lang.String message, java.lang.Throwable throwable) Used to log minor events against the worker.
void	dispose() Set the alive variable to false causing the worker to die.
protected org.apache.excalibur.thread.ThreadControl	execute(org.apache.excalibur.thread.Executable work) Set the Work code this Worker must execute and notifies its thread to do it.
protected void	executeAndWait(org.apache.excalibur.thread.Executable work) Set the Work code this Worker must execute and notifies its thread to do it.
protected void	postExecute() Overide this method to execute something after each bit of "work".
protected void	preExecute() Overide this method to execute something before each bit of "work".
protected void	recycleThread() Implement this method to replace thread back into pool.
void	run() The main execution loop.
private void	waitForWork() For for new work to arrive or for the thread to be destroyed.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

ENABLE_DEBUG

private static final boolean ENABLE_DEBUG

Enables debug output of major events. Subclasses which implement their own logging do not require this to be true.

See Also:

Constant Field Values

ENABLE_DETAIL_DEBUG

private static final boolean ENABLE_DETAIL_DEBUG

Enables debug output of minor events. Subclasses which implement their own logging do not require this to be true.

See Also:

Constant Field Values

m_work

private org.apache.excalibur.thread.Executable m_work

The work currentlyy associated with worker (May be null).

m_threadControl

private DefaultThreadControl m_threadControl

The thread control associated with current work. Should be null if work is null.

m_alive

private boolean m_alive

True if this thread is alive and not scheduled for shutdown.

m_clearInterruptFlag

private boolean m_clearInterruptFlag

True if this thread needs to clear the interrupt flag

m_pool

private final AbstractThreadPool m_pool

The thread pool this thread is associated with.

Constructor Detail

WorkerThread

protected WorkerThread(AbstractThreadPool pool,
            java.lang.ThreadGroup group,
            java.lang.String name)

Allocates a new Worker object.

Method Detail

run

public final void run()

The main execution loop.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

recycleThread

protected void recycleThread()

Implement this method to replace thread back into pool.

postExecute

protected void postExecute()

Overide this method to execute something after each bit of "work".

preExecute

protected void preExecute()

Overide this method to execute something before each bit of "work".

clearInterruptFlag

public void clearInterruptFlag()

Clears the interrupt flag for this thread. Since Java does not provide a method that does this for an external thread, we have to verify that we are in the WorkerThread. If the code calling this method does not originate from this thread, we set a flag and wait for it to be called internally.

dispose

public void dispose()

Set the alive variable to false causing the worker to die. If the worker is stalled and a timeout generated this call, this method does not change the state of the worker (that must be destroyed in other ways).

This is called by the pool when it is removed.

execute

protected org.apache.excalibur.thread.ThreadControl execute(org.apache.excalibur.thread.Executable work)

Set the Work code this Worker must execute and notifies its thread to do it.

executeAndWait

protected void executeAndWait(org.apache.excalibur.thread.Executable work)

Set the Work code this Worker must execute and notifies its thread to do it. Wait until the executable has finished before returning.

waitForWork

private void waitForWork()

For for new work to arrive or for the thread to be destroyed.

debug

protected void debug(java.lang.String message)

Used to log major events against the worker. Creation, deletion, uncaught exceptions etc.

This implementation is a Noop. Subclasses can override to actually do some logging.

Parameters:

message - Message to log.

debug

protected void debug(java.lang.String message,
         java.lang.Throwable throwable)

Used to log major events against the worker. Creation, deletion, uncaught exceptions etc.

This implementation is a Noop. Subclasses can override to actually do some logging.

Parameters:

message - Message to log.

throwable - Throwable to log with the message.

detailDebug

protected void detailDebug(java.lang.String message)

Used to log minor events against the worker. Start and stop of individual pieces of work etc. Separated from the major events so that they are not lost in a sea of minor events.

This implementation is a Noop. Subclasses can override to actually do some logging.

Parameters:

message - Message to log.

detailDebug

protected void detailDebug(java.lang.String message,
               java.lang.Throwable throwable)

Used to log minor events against the worker. Start and stop of individual pieces of work etc. Separated from the major events so that they are not lost in a sea of minor events.

This implementation is a Noop. Subclasses can override to actually do some logging.

Parameters:

message - Message to log.

throwable - Throwable to log with the message.