When configuring a comma-separated list of class/source directories, they do not get picked up if there's a space after the comma.

This is counterintuitive and the example shown right above the field also has a space – so one would expect it to work.

This issue was noted/confirmed by others as well:

https://groups.google.com/forum/#!searchin/jenkins-jacoco-plugin-mailing-list/space/jenkins-jacoco-plugin-mailing-list/J1fhtFeUxpY/1Bv-Wi3TMFoJ