Java Language
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Java Language log4j / log4j2 Filter Logoutput by level (log4j 1.x)
Example
You can use a filter to log only messages "lower" than e.g. ERROR level. But the filter is not supported by PropertyConfigurator. So you must change to XML config to use it. See log4j-Wiki about filters.
Example "specific level"
<appender name="info-out" class="org.apache.log4j.FileAppender">
<param name="File" value="info.log"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%m%n"/>
</layout>
<filter class="org.apache.log4j.varia.LevelMatchFilter">
<param name="LevelToMatch" value="info" />
<param name="AcceptOnMatch" value="true"/>
</filter>
<filter class="org.apache.log4j.varia.DenyAllFilter" />
</appender>
Or "Level range"
<appender name="info-out" class="org.apache.log4j.FileAppender">
<param name="File" value="info.log"/>
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%m%n"/>
</layout>
<filter class="org.apache.log4j.varia.LevelRangeFilter">
<param name="LevelMax" value="info"/>
<param name="LevelMin" value="info"/>
<param name="AcceptOnMatch" value="true"/>
</filter>
</appender>
