重复 log4j 日志记录

Question

我的类路径中有以下 log4j.xml 文件：

<appender class="org.apache.log4j.ConsoleAppender" name="Console">
    <param name="Threshold" value="info" />
    <layout class="org.apache.log4j.PatternLayout">
        <param value="%d %-5p [%t] %C (%F:%L) - %m%n" name="ConversionPattern"/>
    </layout>
    <filter class="org.apache.log4j.varia.LevelRangeFilter">
      <param value="info" name="LevelMax"/>
      <param value="info" name="LevelMin"/>
    </filter>
</appender>

<logger name="de.scm.cci.importer">
    <level value="info"/>
</logger>

<logger name="com.mchange">
    <level value="info"/>
</logger>
<logger name="jdbc">
    <level value="error"/>
</logger>
<logger name="org.hibernate">
    <level value="info"/>
</logger>
<logger name="org.springframework">
    <level value="info"/>
</logger>

<root>
    <level value="INFO"/>
    <appender-ref ref="Console"/>
</root>

这是输出的前几行：

log4j: Trying to find [log4j.xml] using context classloader sun.misc.Launcher$AppClassLoader@7220722.
log4j: Using URL [file:/opt/app/cci/CCIImporter/jar/log4j.xml] for automatic log4j configuration.
log4j: Preferred configurator class: org.apache.log4j.xml.DOMConfigurator
log4j: System property is :null
log4j: Standard DocumentBuilderFactory search succeded.
log4j: DocumentBuilderFactory is: org.apache.xerces.jaxp.DocumentBuilderFactoryImpl
log4j: debug attribute= "true".
log4j: reset attribute= "false".
log4j: Threshold ="null".
log4j: Retreiving an instance of org.apache.log4j.Logger.
log4j: Setting [de.scm.cci.importer] additivity to [true].
log4j: Level value for de.scm.cci.importer is  [info].
log4j: de.scm.cci.importer level set to INFO
log4j: Retreiving an instance of org.apache.log4j.Logger.
log4j: Setting [com.mchange] additivity to [true].
log4j: Level value for com.mchange is  [info].
log4j: com.mchange level set to INFO
log4j: Retreiving an instance of org.apache.log4j.Logger.
log4j: Setting [jdbc] additivity to [true].
log4j: Level value for jdbc is  [error].
log4j: jdbc level set to ERROR
log4j: Retreiving an instance of org.apache.log4j.Logger.
log4j: Setting [org.hibernate] additivity to [true].
log4j: Level value for org.hibernate is  [info].
log4j: org.hibernate level set to INFO
log4j: Retreiving an instance of org.apache.log4j.Logger.
log4j: Setting [org.springframework] additivity to [true].
log4j: Level value for org.springframework is  [info].
log4j: org.springframework level set to INFO
log4j: Level value for root is  [INFO].
log4j: root level set to INFO
log4j: Class name: [org.apache.log4j.ConsoleAppender]
log4j: Setting property [threshold] to [INFO].
log4j: Parsing layout of class: "org.apache.log4j.PatternLayout"
log4j: Setting property [conversionPattern] to [%d %-5p [%t] %C (%F:%L) - %m%n].
log4j: Setting property [levelMax] to [INFO].
log4j: Setting property [levelMin] to [INFO].
log4j: Adding filter of type [class org.apache.log4j.varia.LevelRangeFilter] to appender named [Console].
log4j: Adding appender named [Console] to category [root].
2014-02-25 13:20:25,534 INFO  [main] de.scm.cci.importer.RunTest (RunTest.java:21) - Starting loop mode
2014-02-25 13:20:25,537 INFO  [main] de.scm.cci.importer.RunTest (RunTest.java:24) - Started...
PERSISTENCE LOADING
2014-02-25 13:20:25,767 INFO  [main] org.springframework.context.support.AbstractApplicationContext (AbstractApplicationContext.java:513) - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@52545254: startup date [Tue Feb 25 13:20:25 CET 2014]; root of context hierarchy
233 [main] INFO org.springframework.context.support.ClassPathXmlApplicationContext  - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@52545254: startup date [Tue Feb 25 13:20:25 CET 2014]; root of context hierarchy
2014-02-25 13:20:25,877 INFO  [main] org.springframework.beans.factory.xml.XmlBeanDefinitionReader (XmlBeanDefinitionReader.java:316) - Loading XML bean definitions from class path resource [de/scm/cci/backend/public/spring-config.xml]

一旦spring开始加载，每一行的输出都会翻倍：

2014-02-25 13:20:25,767 INFO  [main] org.springframework.context.support.AbstractApplicationContext (AbstractApplicationContext.java:513) - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@52545254: startup date [Tue Feb 25 13:20:25 CET 2014]; root of context hierarchy
233 [main] INFO org.springframework.context.support.ClassPathXmlApplicationContext  - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@52545254: startup date [Tue Feb 25 13:20:25 CET 2014]; root of context hierarchy

我完全不知道第二行是从哪里来的。

编辑： 很奇怪：尽管我将所有可能的阈值和内容设置为仅 INFO，但我收到了 WARN 消息...？

Answer 1

因为你只声明了一个 appender，并且重复日志的格式不相同，所以很明显你有多个日志框架同时运行：

• log4j 在您自己的代码中
• Spring 中的公共日志记录

你需要做的是：

• 从类路径中删除 commons-logging 依赖项。如果您使用的是 maven，则必须从 每个 Spring 模块 中排除 commons-logging jar。
• 将 jcl-over-slf4j 添加到您的类路径

Maven 示例（如何删除 commons-logging）：注意：您需要在每个 Spring 依赖项中使用此排除语法

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-web</artifactId>
  <version>${spring.version}</version>
  <exclusions>
    <exclusion>
      <artifactId>commons-logging</artifactId>
      <groupId>commons-logging</groupId>
    </exclusion>
  </exclusions>
</dependency>

Maven 示例（如何添加 slf4j，你可能已经在这样做了）：

<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-api</artifactId>
  <version>1.7.7</version>
</dependency>

<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>jcl-over-slf4j</artifactId>
  <version>1.7.7</version>
</dependency>

如果您不使用 Maven，请告诉我，我会尽力帮助您处理特定环境。

Answer 2

Spring Framework 不直接使用 log4j - 它使用 commons-logging。

它的行为将取决于您的应用程序类路径中的其他日志记录实现。

您的类路径中有哪些与日志记录相关的 jar？