Android Question Type

Hello to all
doubt!
I have several Type in a module
is it preferable to put them in the Starter class?

The question is for this mistake
where t_artcomanda is a Type in module BAR.Tablet.db_type

java.lang.ClassNotFoundException: Didn't find class "BAR.Tablet.db_type$_t_artcomanda" on path: DexPathList[[zip file "/data/app/BAR.Tablet-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]

Thank you