您可以使用LevelMatchFilter完成任务.此外,您不应该忘记使用另一个过滤器 - DenyAllFilter - 作为过滤器链中的最后一个过滤器.
您的log4j.xml将如下所示:
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
<appender name="consoleAppender" class="org.apache.log4j.ConsoleAppender">
<layout class="org.apache.log4j.SimpleLayout" />
<filter class="org.apache.log4j.varia.LevelMatchFilter">
<param name="LevelToMatch" value="ERROR" />
<param name="AcceptOnMatch" value="true" />
</filter>
<filter class="org.apache.log4j.varia.DenyAllFilter" />
</appender>
<appender name="fileAppender" class="org.apache.log4j.FileAppender">
<param name="File" value="error.log" />
<layout class="org.apache.log4j.SimpleLayout" />
<filter class="org.apache.log4j.varia.LevelMatchFilter">
<param name="LevelToMatch" value="WARN" />
<param name="AcceptOnMatch" value="true" />
</filter>
<filter class="org.apache.log4j.varia.DenyAllFilter" />
</appender>
<logger name="foo">
<level value="WARN" />
<appender-ref ref="consoleAppender" />
<appender-ref ref="fileAppender" />
</logger>
</log4j:configuration>
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