com.neeve.rog.log
Class RogLogCompactor

java.lang.Object
  com.neeve.root.RootObject
      com.neeve.rog.RogObject
          com.neeve.rog.log.RogLogCompactor

public final class RogLogCompactor
extends RogObject

Compacts a log's live log file

Threading:

A log compactor is not safe for concurrent access by multiple threads.

Nested Class Summary

static class

RogLogCompactor.State Enmerates the various compactor states

Method Summary

RogLogCompactor	compact() Perform the log compaction This method kicks off the background compaction of the live transaction log file.
RogLogCompactor	compact(long forceCheckpointCompletionOn) Perform the log compaction
long	getMaxCompactionWindowSize() Gets the compaction window size.
RogLogCompactor.State	getState() Get the current compaction state
boolean	isCompactionInProgress() Get is compaction is in progress
void	setMaxCompactionWindowSize(long size) May be used to change the compaction windows size.
void	stop() Stop any running compaction
void	waitForCompactionToComplete() Wait for compaction to complete

Methods inherited from class com.neeve.root.RootObject

getChecked, getThreaded, getTracer, setChecked, setTracer

Methods inherited from class java.lang.Object

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

Method Detail

setMaxCompactionWindowSize

public final void setMaxCompactionWindowSize(long size)

May be used to change the compaction windows size.

Parameters:

size - The size (in megabytes to set for the compaction window.

Throws:

IllegalStateException - if isCompactionInProgress() is true.

IllegalArgumentException - if the compaction window size is invalid (<=0).

getMaxCompactionWindowSize

public final long getMaxCompactionWindowSize()

Gets the compaction window size.

Returns:

The current compaction window size in megabytes.

getState

public final RogLogCompactor.State getState()

Get the current compaction state

compact

public final RogLogCompactor compact(long forceCheckpointCompletionOn)

Perform the log compaction

Parameters:

forceCheckpointCompletionOn - Specifies a checkpoint version that forces the completion of a checkpoint in the compacted log. This value is used in conjunction with the compaction window to determine when to complete a checkpoint in the compacted log. A value of <=0 in this parameter will cause only the compaction window to be used. A value of > 0 will cause the compaction window to be used but will force the checkpoint to be completed immediately after processing the checkpoint version specified in this parameter.

This method kicks off the background compaction of the live transaction log file. The caller can track the status of the compaction by polling the state via the getState() method.

compact

public final RogLogCompactor compact()

Perform the log compaction

This method kicks off the background compaction of the live transaction log file. The caller can track the status of the compaction by polling the state via the getState() method.

isCompactionInProgress

public final boolean isCompactionInProgress()

Get is compaction is in progress

waitForCompactionToComplete

public final void waitForCompactionToComplete()
                                       throws Exception

Wait for compaction to complete

Throws:

Exception

stop

public final void stop()

Stop any running compaction