Am using log4j as follows :
<appender name="LOGFILE" class="org.apache.log4j.DailyRollingFileAppender">
<param name="File" value="D:/direc/logs/back-${batch}-${dateexec}.log" />
<param name="DatePattern" value="'.'yyyy-MM-dd-HH" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern"
value="%d{dd MMM yyyy - HH:mm:ss,SSS} [%t] %-5p [%c] %M : (ligne %L) - %m %n" />
</layout>
</appender>
where {batch} and {dateexec} should refer to variables[from command parameters ] (batch name and execution time).
in this case the log file name is "back--.log"
Does any one knows how it works ?