java - Log4j 2 中的文件模式有什么用？

Question

我对 log4j 2 中 RollingFile Appender 的文件模式有疑问。RollingFile 需要一个 FileName 和 FilePattern，但我不知道 FilePattern 的作用。我认为它只是被忽略了。这是我的 log4j2.xml 的一部分

<Property name="pattern">
    %-5p [%d{dd.MM.yyyy - HH:mm:ss}] : %m%n %ex
</Property>

<Property name="MainLoggerPath">
    C:/logs/MainLogger.log
</Property>

<Property name="FilePattern">
    C:/logs/$${date:yyyy-MM}/app-%d{MM- dd-yyyy}-%i.log.gz
</Property>


<RollingFile name="MainAppender" fileName="${MainLoggerPath}"
filePattern="${FilePattern}">

    <ThresholdFilter level="ALL" onMatch="ACCEPT" onMismatch="DENY" />

    <PatternLayout 
    pattern="${pattern}" />

    <Policies>
        <SizeBasedTriggeringPolicy size="10 MB" />
    </Policies>

    <DefaultRolloverStrategy max="10" />

</RollingFile>    

Answer 1

关于 documentation :

The pattern of the file name of the archived log file. The format of the pattern is dependent on the RolloverPolicy that is used. The DefaultRolloverPolicy will accept both a date/time pattern compatible with SimpleDateFormat and/or a %i which represents an integer counter. The pattern also supports interpolation at runtime so any of the Lookups (such as the DateLookup can be included in the pattern.