Logging

In the retepMicroKernel environment all logging is done with Log4J.

Configuration

An application can provide it's own Log4J configuration by placing an xml file into the etc directory. There's two possible names for this file, etc/appName.log4j.xml where appName is the application's name or etc/log4j.xml

When the kernel starts, the first thing it does is looks for the application specific file. If that is not found it then looks for the global log4j.xml file. If that does not exist it then uses a default xml file located within the Kernel itself and documented below.

The reason for this algorithm is to allow individual log4j configuration for applications that are deployed together - i.e. share the same home directory but keep their logging separate.

Default configuration

If no Log4J configuration is provided the kernel defaults so that logging is directed to stdout using the following definition:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
    <appender name="CONSOLE" class="org.apache.log4j.ConsoleAppender">
        <param name="Target" value="System.out"/>
        <param name="Threshold" value="INFO"/>
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d{ABSOLUTE} %-5p [%-12c{1}] %m%n"/>
        </layout>
    </appender>
    <root>
        <appender-ref ref="CONSOLE"/>
    </root>
</log4j:configuration>