filename support has been recently added to Multipart-Forms:
https://issues.jboss.org/browse/RESTEASY-876

It would be nice if a mechanism to define the filename for a @MultipartForm annotated class is added.

So a class like this could also define it's filename for "data":

public class Attachment {
	@FormParam("file")
	@PartType("text/plain")
	private byte[] data;
}

It would be important to be able to assign the name dynamically and not only with an annotation like

@FormParamName("Test")