I've found this QA already and was able to prevent the generation of classes, but enums are still generated.
I've tried to prevent it with custom binding:
<jxb:bindings node="//xs:simpleType[@name='myEnum']">
<jxb:class ref="com.myapp.enums.MyEnum" />
</jxb:bindings>
but it is not working for me. Is there any possibility to prevent the generation of enums or maybe another customization?