proai.cache
Class Committer

java.lang.Object
  java.lang.Thread
      proai.cache.Committer

All Implemented Interfaces:

java.lang.Runnable

public class Committer
extends java.lang.Thread

A thread for committing a series of QueueItem updates to the database.

Items are added to a "commit queue" by Worker threads via the synchronized handoff() method. This can occur before the thread is actually started. Once the thread is started, the items are removed asynchronously, then committed, until all workers have finished and ( the queue is empty or processing has been aborted ).

Author:

Chris Wilper

Nested Class Summary

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

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

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Committer(Updater updater, RCDatabase db, int maxCommitQueueSize, int maxRecordsPerTransaction)
Construct a new committer with the given configuration.

Method Summary

protected int	getProcessedCount()
protected long	getTotalCommitTime()
protected int	getTransactionCount()
protected boolean	handoff(java.util.List<QueueItem> queueItems) Attempt to add the list of QueueItems to the commit queue and return immediately.
void	run() Run the thread.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, 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

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

Constructor Detail

Committer

public Committer(Updater updater,
                 RCDatabase db,
                 int maxCommitQueueSize,
                 int maxRecordsPerTransaction)
          throws ServerException

Construct a new committer with the given configuration. The caller is responsible for actually starting the thread.

Throws:

ServerException

Method Detail

handoff

protected boolean handoff(java.util.List<QueueItem> queueItems)

Attempt to add the list of QueueItems to the commit queue and return immediately. This method will block until adding the list would not cause the queue to exceed its capacity or the thread is finished running.

Returns:

whether the handoff was successful. The handoff will only fail if the Committer thread has been stopped.

run

public void run()

Run the thread. This works in two phases. The first phase executes while workers are running and the second phase commits all remaining items unless processing is aborted.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

getTransactionCount

protected int getTransactionCount()

getProcessedCount

protected int getProcessedCount()

getTotalCommitTime

protected long getTotalCommitTime()