Technical Beef -

In hosted mode, GWT redirects all the logging calls made with commons-logging to its own "TreeLogger", so that any useful logs emitted server-side are redirected to it (and most likely lost). Not only is this annoying, it also breaks the expected consistency with the normal deployment state.

Technically, the GWT makes a System.setProperty("org.apache.commons.logging.Log", adapterClassName) call. Fortunately, the apache commons logging library preempts this setting with its own configuration file.

Just create a file called "commons-logging.properties" at the root of your classpath, and add the following line:

[to use the Log4j backend]

org.apache.commons.logging.Log=org.apache.commons.logging.impl.Log4JLogger

[to use the JDK14 backend]

org.apache.commons.logging.Log=org.apache.commons.logging.impl.Jdk14Logger

[to use the SimpleLog backend]

org.apache.commons.logging.Log=org.apache.commons.logging.impl.SimpleLog

etc. well, you got it.

(OK, the title of this article is misleading, we're not really asking the GWT to not redirect, but rather asking commons-logging to ignore the GWT request)