log4j:WARN No appenders could be found for logger in web.xml

Question

I already put the log4jConfigLocation in web.xml, but I still get the following warning:

log4j:WARN No appenders could be found for logger ⤦     ⤥ (org.springframework.web.context.ContextLoader). log4j:WARN Please initialize the log4j system properly. 

What did I miss?

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"      "java.sun.com/dtd/web-app_2_3.dtd"> <web-app>     <context-param>         <param-name>contextConfigLocation</param-name>         <param-value>             /WEB-INF/applicationContext.xml         </param-value>     </context-param>     <context-param>         <param-name>log4jConfigLocation</param-name>         <param-value>/WEB-INF/classes/log4j.properties</param-value>     </context-param>      <listener>         <listener-class>             org.springframework.web.util.Log4jConfigListener         </listener-class>     </listener>     <listener>         <listener-class>             org.springframework.web.context.ContextLoaderListener         </listener-class>     </listener>      <servlet>         <servlet-name>suara2</servlet-name>         <servlet-class>             org.springframework.web.servlet.DispatcherServlet         </servlet-class>     </servlet>     <servlet-mapping>         <servlet-name>suara2</servlet-name>         <url-pattern>/*</url-pattern>     </servlet-mapping> </web-app> 

Answer 1

If that's the entire log4j.properties file it looks like you're never actually creating a logger. You need a line like:

log4j.rootLogger=debug,A1 

Answer 2

I had log4j.properties in the correct place in the classpath and still got this warning with anything that used it directly. Code using log4j through commons-logging seemed to be fine for some reason.

If you have:

log4j.rootLogger=WARN 

Change it to:

log4j.rootLogger=WARN, console log4j.appender.console=org.apache.log4j.ConsoleAppender log4j.appender.console.layout=org.apache.log4j.PatternLayout log4j.appender.console.layout.conversionPattern=%5p [%t] (%F:%L) - %m%n 

According to http://logging.apache.org/log4j/1.2/manual.html:

The root logger is anonymous but can be accessed with the Logger.getRootLogger() method. There is no default appender attached to root.

What this means is that you need to specify some appender, any appender, to the root logger to get logging to happen.

Adding that console appender to the rootLogger gets this complaint to disappear.