Question

I have the following log4j.properties file, for an application deployed in WebSphere Portal:

log4j.rootLogger=DEBUG, InfoAppender, DebugAppender

log4j.appender.InfoAppender=org.apache.log4j.RollingFileAppender
log4j.appender.InfoAppender.Threshold=INFO
log4j.appender.InfoAppender.File=C:/info.log
log4j.appender.InfoAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.InfoAppender.layout.ConversionPattern=%d %p [%c] - %m%n

log4j.appender.DebugAppender=org.apache.log4j.RollingFileAppender
log4j.appender.DebugAppender.Threshold=DEBUG
log4j.appender.DebugAppender.File=C:/debug.log
log4j.appender.DebugAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.DebugAppender.layout.ConversionPattern=%d %p [%c] - %m%n

When I code, I define the logger at class level:

private static Logger logger = Logger.getLogger(IWannaLogThis.class);

And I log INFO messages with this:

logger.info(theObjectToLog);

When I deploy my application, the debug.log file gets everything I log with logger.debug() but ignores everything I write with logger.info(). On the other side, the info.log file keeps empty.

The weirdest thing is that in debug.log and info.log appears some INFO and DEBUG messages made by some JARS (like Hibernate Validator) I had in the classpath, but just ignores everything I try to log in my code.

Any ideas?

Answer 1

This is most likely a classloading-related problem. WebSphere Portal uses Log4J internally, so I’m guessing that you end up using WebSphere Portal’s provided Log4J JAR file as well as its own Log4J properties.

You can verify that by adding the following to the JVM arguments of the server instance:

-Dlog4j.debug=true

And then inspect the SystemOut.log file. Log4J will spit out lots of tracing information about the configuration file(s) it reads.

The best way to avoid this is to do the following:

1. Bundle the Log4J JAR file with your application.
2. Associate a Shared Library with the server. In that Shared Library, place your Log4J configuration file.

As an alternative to step 2, you can bundle your Log4J configuration file with the application itself, however that would carry its own drawbacks (for example, having to repackage your application whenever you perform a Log4J configuration change).