Running one of the examples with e.g mvn verify will typically create and leave behind an unexpected sub directory within the example source dir called "${sys:artemis.instance}/log" with [empty] artemis.log and audit.log files inside. Alternatively, on some systems it may instead fail while trying to do this and display an error message about it.

This happens because the plugin used by the examples first creates a broker instance within the target directory, prompting creation of a related log4j2.properties file, then at the end of the example the plugin is again used to run the CLI stop command to shut down the broker, the process for which currently runs the CLI class directly without some of the configuration properties the CLI script normally sets, and in doing this puts the broker instance log42.properties file on the classpath and then causes log4j to be initialised which leads to the erroneous dir+file creation due to the missing props. We can resolve this by updating the example/plugin to call the CLI script such that the needed config is actually present.