org.apache.log4j.varia
Class LogFilePatternReceiver

java.lang.Object
  org.apache.log4j.spi.ComponentBase
      org.apache.log4j.plugins.PluginSkeleton
          org.apache.log4j.plugins.Receiver
              org.apache.log4j.varia.LogFilePatternReceiver

All Implemented Interfaces:

org.apache.log4j.plugins.Plugin, org.apache.log4j.spi.Component, org.apache.log4j.spi.OptionHandler, org.apache.log4j.spi.Thresholdable

public class LogFilePatternReceiver
extends org.apache.log4j.plugins.Receiver

LogFilePatternReceiver can parse and tail log files, converting entries into LoggingEvents. If the file doesn't exist when the receiver is initialized, the receiver will look for the file once every 10 seconds.

This receiver relies on ORO Perl5 features to perform the parsing of text in the log file, however the only regular expression field explicitly supported is a glob-style wildcard used to ignore fields in the log file if needed. All other fields are parsed by using the supplied keywords.

Features:
- specify the URL of the log file to be processed
- specify the timestamp format in the file (if one exists)
- specify the pattern (logFormat) used in the log file using keywords, a wildcard character (*) and fixed text
- 'tail' the file (allows the contents of the file to be continually read and new events processed)
- supports the parsing of multi-line messages and exceptions - 'hostname' property set to URL host (or 'file' if not available) - 'application' property set to URL path (or value of fileURL if not available)

Keywords:
TIMESTAMP
LOGGER
LEVEL
THREAD
CLASS
FILE
LINE
METHOD
RELATIVETIME
MESSAGE
NDC
PROP(key)

Use a * to ignore portions of the log format that should be ignored

Example:
If your file's patternlayout is this:
%d %-5p [%t] %C{2} (%F:%L) - %m%n

specify this as the log format:
TIMESTAMP LEVEL [THREAD] CLASS (FILE:LINE) - MESSAGE

To define a PROPERTY field, use PROP(key)

Example:
If you used the RELATIVETIME pattern layout character in the file, you can use PROP(RELATIVETIME) in the logFormat definition to assign the RELATIVETIME field as a property on the event.

If your file's patternlayout is this:
%r [%t] %-5p %c %x - %m%n

specify this as the log format:
PROP(RELATIVETIME) [THREAD] LEVEL LOGGER * - MESSAGE

Note the * - it can be used to ignore a single word or sequence of words in the log file (in order for the wildcard to ignore a sequence of words, the text being ignored must be followed by some delimiter, like '-' or '[') - ndc is being ignored in this example.

Assign a filterExpression in order to only process events which match a filter. If a filterExpression is not assigned, all events are processed.

Limitations:
- no support for the single-line version of throwable supported by patternlayout
(this version of throwable will be included as the last line of the message)
- the relativetime patternLayout character must be set as a property: PROP(RELATIVETIME)
- messages should appear as the last field of the logFormat because the variability in message content
- exceptions are converted if the exception stack trace (other than the first line of the exception)
is stored in the log file with a tab followed by the word 'at' as the first characters in the line
- tailing may fail if the file rolls over.

Example receiver configuration settings (add these as params, specifying a LogFilePatternReceiver 'plugin'):
param: "timestampFormat" value="yyyy-MM-d HH:mm:ss,SSS"
param: "logFormat" value="RELATIVETIME [THREAD] LEVEL LOGGER * - MESSAGE"
param: "fileURL" value="file:///c:/events.log"
param: "tailing" value="true"

This configuration will be able to process these sample events:
710 [ Thread-0] DEBUG first.logger first - something here something else
880 [ Thread-2] DEBUG first.logger third - something here something else
880 [ Thread-0] INFO first.logger first - infomsg-0
java.lang.Exception: someexception-first
at Generator2.run(Generator2.java:102)

Author:

Scott Deboy

Field Summary

Fields inherited from class org.apache.log4j.plugins.Receiver

thresholdLevel

Fields inherited from class org.apache.log4j.plugins.PluginSkeleton

active, name

Fields inherited from class org.apache.log4j.spi.ComponentBase

repository

Constructor Summary

LogFilePatternReceiver()

Method Summary

void	activateOptions() Read and process the log file.
protected void	createPattern() create the regular expression pattern using the input regular expression
java.lang.String	getFileURL() Accessor
java.lang.String	getFilterExpression() Accessor
java.lang.String	getLogFormat() Accessor
java.lang.String	getTimestampFormat() Accessor
protected void	initialize() Build the regular expression needed to parse log entries
boolean	isTailing() Accessor
boolean	isUseCurrentThread() When true, this property uses the current Thread to perform the import, otherwise when false (the default), a new Thread is created and started to manage the import.
static void	main(java.lang.String[] args)
protected void	process(java.io.BufferedReader bufferedReader) Read, parse and optionally tail the log file, converting entries into logging events.
void	setFileURL(java.lang.String fileURL) Mutator
void	setFilterExpression(java.lang.String filterExpression) Mutator
protected void	setHost(java.lang.String host)
void	setLogFormat(java.lang.String logFormat) Mutator
protected void	setPath(java.lang.String path)
void	setTailing(boolean tailing) Mutator
void	setTimestampFormat(java.lang.String timestampFormat) Mutator
void	setUseCurrentThread(boolean useCurrentThread) Sets whether the current Thread or a new Thread is created to perform the import, the default being false (new Thread created).
void	shutdown() Close the reader.

Methods inherited from class org.apache.log4j.plugins.Receiver

doPost, getThreshold, isAsSevereAsThreshold, setThreshold

Methods inherited from class org.apache.log4j.plugins.PluginSkeleton

addPropertyChangeListener, addPropertyChangeListener, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getLoggerRepository, getName, isActive, isEquivalent, removePropertyChangeListener, removePropertyChangeListener, setLoggerRepository, setName

Methods inherited from class org.apache.log4j.spi.ComponentBase

getLogger, getNonFloodingLogger, resetErrorCount

Methods inherited from class java.lang.Object

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

Constructor Detail

LogFilePatternReceiver

public LogFilePatternReceiver()

Method Detail

getFileURL

public java.lang.String getFileURL()

Accessor

Returns:

file URL

setFileURL

public void setFileURL(java.lang.String fileURL)

Mutator

Parameters:

fileURL -

getFilterExpression

public java.lang.String getFilterExpression()

Accessor

Returns:

filter expression

setFilterExpression

public void setFilterExpression(java.lang.String filterExpression)

Mutator

Parameters:

filterExpression -

isTailing

public boolean isTailing()

Accessor

Returns:

tailing

setTailing

public void setTailing(boolean tailing)

Mutator

Parameters:

tailing -

isUseCurrentThread

public final boolean isUseCurrentThread()

When true, this property uses the current Thread to perform the import, otherwise when false (the default), a new Thread is created and started to manage the import.

Returns:

setUseCurrentThread

public final void setUseCurrentThread(boolean useCurrentThread)

Sets whether the current Thread or a new Thread is created to perform the import, the default being false (new Thread created).

Parameters:

useCurrentThread -

getLogFormat

public java.lang.String getLogFormat()

Accessor

Returns:

log format

setLogFormat

public void setLogFormat(java.lang.String logFormat)

Mutator

Parameters:

logFormat - the format

setTimestampFormat

public void setTimestampFormat(java.lang.String timestampFormat)

Mutator

Parameters:

timestampFormat -

getTimestampFormat

public java.lang.String getTimestampFormat()

Accessor

Returns:

timestamp format

process

protected void process(java.io.BufferedReader bufferedReader)
                throws java.io.IOException

Read, parse and optionally tail the log file, converting entries into logging events. A runtimeException is thrown if the logFormat pattern is malformed according to ORO's Perl5Compiler.

Parameters:

unbufferedReader -

Throws:

java.io.IOException

createPattern

protected void createPattern()

create the regular expression pattern using the input regular expression

setHost

protected void setHost(java.lang.String host)

setPath

protected void setPath(java.lang.String path)

initialize

protected void initialize()

Build the regular expression needed to parse log entries

main

public static void main(java.lang.String[] args)

shutdown

public void shutdown()

Close the reader.

activateOptions

public void activateOptions()

Read and process the log file.