JavaBean Data Adapter and adding Fields in Dataset and Query dialog

[sonja.borer]

Hello,

I am trying to add an JavaBean Data Adapter to my report, which works out fine. Test says successfull!

My next step is to create a new Report and right click on it > Dataset and Query...
on top i have to select my DataSource -> i choose the one i created successfully before.
below i check Java Bean, which switches me to an formular where i shall select the class name.

i know the name of the class file and enter it, but Jaspersoft Studio does not find my class.

how can i fix this?
As the Test says successful i wonder why Studio does not find my jar anymore.