Logging configuration
Logging layout patterns
The pattern of each individual line logged by log4j can be customized in the layout element of an appender. See the following example:
Log Layout Appender Example
<appender name="SERVER" class="org.apache.log4j.RollingFileAppender">
<errorHandler class="org.apache.log4j.helpers.OnlyOnceErrorHandler"/>
<param name="File" value="log/nevislogrend.log"/>
<param name="Append" value="true"/>
<param name="MaxFileSize" value="10MB"/>
<param name="MaxBackupIndex" value="9"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d{ISO8601} %-15.15t %-40.40c %-5.5p %X{indent}%m%n"/>
</layout>
</appender>
The above example will prefix log lines with the following, and in that order:
- a date/time timestamp (
%d
), - the thread name (
%t
), - the conversation ID (
%X{conversationId}
), - the trace group (
%c
) - the priority of the trace message (
%p
).
It will also indent traces (%X{indent}
).
Important trace groups
The following list shows the most important general trace groups, in combination with relevant debugging use cases:
Full trace analysis (debugging in test environment only)
<root>
<priority value="DEBUG"/>
<appender-ref ref="SERVER"/>
</root>General debugging
<category name="ch.nevis.logrend">
<priority value="INFO"/>
</category>General debugging translation / GuiDescriptor problems
<category name="ch.nevis.logrend.beans.LoginBean">
<priority value="DEBUG"/>
</category>Low level debugging
<category name="org.eclipse.jetty">
<priority value="DEBUG"/>
</category>
info
For all logging groups and their description, see the log4j configuration of your instance. If you need more examples, check the default configuration template here: /opt/nevislogrend/template/conf/log4j.xml