java - Own transferable returns no DataFlavor from outside application -

i have 2 applications:

1. own image explorer. want operate images via such options copy-paste. created own dataflavor type this. (yeah, need that!) looks

dataflavor supportedflavor = new dataflavor(app.my.imagewrapper.class, "imagewrapper class"); 

and in transferable use dataflavor:

            @override         public boolean isdataflavorsupported(dataflavor flavor) {             return supportedflavor.equals(flavor);         }          @override         public dataflavor[] gettransferdataflavors() {             return new dataflavor[]{supportedflavor}; // simpled sscce, don't create new flavor each time         } 

2. flavorlistener this answer. should listen flavorevents detecting data type copied.

my problem is:

when event other application after copying text, files, images, dataflavor never null. if event after copying object, cannot detect dataflavor. why?

ps: sorry bad english.

thanks everyone, i've found answer here after looking related section. wasn't show in search field, strange, because second time similar situation...