log4j 日志打印2遍

Question

日志如下:

[INFO] org.springframework.web.context.ContextLoader,2016-07-26 19:22:29,865,Root WebApplicationContext: initialization started
[INFO] org.springframework.web.context.ContextLoader,2016-07-26 19:22:29,865,Root WebApplicationContext: initialization started
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,141,Initializing new StandardServletEnvironment
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,141,Initializing new StandardServletEnvironment
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,144,Adding [servletConfigInitParams] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,144,Adding [servletConfigInitParams] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,145,Adding [servletContextInitParams] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,145,Adding [servletContextInitParams] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,160,Adding [jndiProperties] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,160,Adding [jndiProperties] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,161,Adding [systemProperties] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,161,Adding [systemProperties] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,161,Adding [systemEnvironment] PropertySource with lowest search precedence
[DEBUG] org.springframework.web.context.support.StandardServletEnvironment,2016-07-26 19:22:30,161,Adding [systemEnvironment] PropertySource with lowest search precedence

全部输出2次,感觉像是项目启动了2次一样.

log4j.xml配置如下:

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">


<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">


  <appender name="CONSOLE" class="org.apache.log4j.ConsoleAppender">
    <layout class="org.apache.log4j.PatternLayout">
      <param name="ConversionPattern" value="[%p] %c,%d{yyyy-MM-dd HH

Answer 1

引用来自“小王爷威武”的评论

因为配置了这一段：

<logger name="org.springframework" additivity="true"> <level value="DEBUG"/> <appender-ref ref="CONSOLE"/> </logger>

所以
org.springframework.web.context.ContextLoader就打印了日志。

而且还配置了additivity="true"，所以还会找上一级日志：org.springframework.web.context，

没有的话，再找org.springframework.web，依此类推，找到org都没有，再往上找就是root了。

<root> <priority value="DEBUG"/> <appender-ref ref="ERROR_FILE_LOG"/> <appender-ref ref="DEBUG_FILE_LOG"/> <appender-ref ref="CONSOLE"/> </root>

root你已经配置了，所以又打印了

Answer 2

因为配置了这一段：

<logger name="org.springframework" additivity="true"> <level value="DEBUG"/> <appender-ref ref="CONSOLE"/> </logger>

所以
org.springframework.web.context.ContextLoader就打印了日志。

而且还配置了additivity="true"，所以还会找上一级日志：org.springframework.web.context，

没有的话，再找org.springframework.web，依此类推，找到org都没有，再往上找就是root了。

<root> <priority value="DEBUG"/> <appender-ref ref="ERROR_FILE_LOG"/> <appender-ref ref="DEBUG_FILE_LOG"/> <appender-ref ref="CONSOLE"/> </root>

root你已经配置了，所以又打印了