Package org.apache.log4j.chainsaw

Chainsaw is a GUI log viewer and filter for the log4j package.


Class Summary
Main The main application.

Package org.apache.log4j.chainsaw Description

Chainsaw is a GUI log viewer and filter for the log4j package. By default it listens for LoggingEvent objects sent using the SocketAppender and displays them in a table. The events can be filtered based on:

All the details for each event can be displayed by selecting the event in the table.

Chainsaw also supports loading a events logged to a file using the XMLLayout format. This is great for analysing log files, and means you do not need to keep Chainsaw running continously. It is easy to add support for loading events from other sources like JDBC.

A picture is worth a thousand words:

Screen shot of chainsaw.

Finally, why is it called chainsaw? Because it cuts your log (file) down to size. :-)


Chainsaw is based on the Swing API which requires JDK 1.2 or later.

Running chainsaw


You need to include the log4j.jar in the classpath.


The command line usage is:

  java -D<property>=<value> org.apache.log4j.chainsaw.Main 

The default behaviour of chainsaw can be changed by setting system properties using the -D<property>=<value> arguments to java. The following table describes what properties can be set:

Property Description
chainsaw.port Indicates which port to listen for connections on. Defaults to "4445".

Configuring Log4J

You will need to configure log4j to send logging events to Chainsaw. Here is a sample file for sending logging events to Chainsaw.


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