kieker.monitoring.writer.filesystem
Class SyncFsWriter

java.lang.Object
  kieker.monitoring.writer.AbstractMonitoringWriter
      kieker.monitoring.writer.filesystem.SyncFsWriter

All Implemented Interfaces:

IMonitoringRecordReceiver, IMonitoringWriter

public final class SyncFsWriter
extends AbstractMonitoringWriter

Simple class to store monitoring data in the file system. Although a buffered writer is used, outliers (delays of 1000 ms) occur from time to time if many monitoring events have to be written. We believe that outliers result from a flush on the buffer of the writer. A more sophisticated writer to store data in the file system is the AsyncFsWriter. This does not introduce the outliers that result from flushing the writing buffer, since provides an asynchronous insertMonitoringData method. However, the AsyncFsWriter introduces a little more overhead because a writing queue is required and it isn't tested as much as the FileSystenWriter. Additionally, the resource demands (CPU, bus etc.) for writing monitoring data are not anymore occurring during the time of the execution that is monitored, but at some other (unknown) time. The AsyncFsWriter should usually be used instead of this class to avoid the outliers described above.

Since:

< 0.9

Author:

Matthias Rohr, Andre van Hoorn, Jan Waller

Field Summary

static java.lang.String	CONFIG_BUFFER
static java.lang.String	CONFIG_FLUSH
static java.lang.String	CONFIG_MAXENTRIESINFILE
static java.lang.String	CONFIG_MAXLOGFILES
static java.lang.String	CONFIG_MAXLOGSIZE
static java.lang.String	CONFIG_PATH

Fields inherited from class kieker.monitoring.writer.AbstractMonitoringWriter

monitoringController

Constructor Summary

SyncFsWriter(Configuration configuration)
Creates a new instance of this class using the given configuration to initialize the class.

Method Summary

protected void	init() Implementing classes should indicate an initialization error by throwing an Exception.
boolean	newMonitoringRecord(IMonitoringRecord monitoringRecord) Called for each new record.
void	terminate() Called by the Monitoring Controller to announce a shutdown of monitoring.
java.lang.String	toString() Delivers a string representation of this writer.

Methods inherited from class kieker.monitoring.writer.AbstractMonitoringWriter

getDefaultConfiguration, newMonitoringRecordNonBlocking, setController

Methods inherited from class java.lang.Object

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

Field Detail

CONFIG_PATH

public static final java.lang.String CONFIG_PATH

CONFIG_MAXENTRIESINFILE

public static final java.lang.String CONFIG_MAXENTRIESINFILE

CONFIG_MAXLOGSIZE

public static final java.lang.String CONFIG_MAXLOGSIZE

CONFIG_MAXLOGFILES

public static final java.lang.String CONFIG_MAXLOGFILES

CONFIG_FLUSH

public static final java.lang.String CONFIG_FLUSH

CONFIG_BUFFER

public static final java.lang.String CONFIG_BUFFER

Constructor Detail

SyncFsWriter

public SyncFsWriter(Configuration configuration)
             throws java.lang.IllegalArgumentException

Creates a new instance of this class using the given configuration to initialize the class.

Parameters:

configuration - The configuration used to initialize this writer.

Throws:

java.lang.IllegalArgumentException - If the given configuration is invalid.

Method Detail

init

protected void init()
             throws java.lang.IllegalArgumentException,
                    java.io.IOException

Description copied from class: AbstractMonitoringWriter

Implementing classes should indicate an initialization error by throwing an Exception.

Specified by:

init in class AbstractMonitoringWriter

Throws:

java.lang.IllegalArgumentException

java.io.IOException

newMonitoringRecord

public final boolean newMonitoringRecord(IMonitoringRecord monitoringRecord)

Called for each new record. Notice, that this method should not throw an exception, but indicate an error by the return value false.

Parameters:

monitoringRecord - the record.

Returns:

true on success; false in case of an error.

terminate

public final void terminate()

Called by the Monitoring Controller to announce a shutdown of monitoring. Writers should return as soon as it is safe to terminate Kieker.

toString

public final java.lang.String toString()

Description copied from interface: IMonitoringWriter

Delivers a string representation of this writer.

Specified by:

toString in interface IMonitoringWriter

Overrides:

toString in class AbstractMonitoringWriter

Returns:

A string.