class A {
 @Convert(converter = B.Converter::class, dbType = String::class)
 var b:B?=null
 @Convert(converter = C.Converter::class, dbType = String::class)
 var c:C?=null
}
class B {
 class Converter...
}
class C {
 class Converter...
}

...
import apple.ios.watches.model.B;
import apple.ios.watches.model.C;
...
private final B.Converter bConverter = new B.Converter();
private final C.Converter cConverter = new C.Converter();
...

...
import apple.ios.watches.model.B.Converter;
import apple.ios.watches.model.C.Converter;
...
private final Converter bConverter = new Converter();
private final Converter cConverter = new Converter();
...