Output maps of multipart/form-data
23.9. Multipart FormData Output with java.util.Map If your body parts are uniform, you do not have to manually marshall each and every part or even use a MultipartFormDataOutput object.. You can just provide a java.util.Map. It must have the generic type it is marshalling with the generic parameter of the Map type declaration. You must also annotate the method with the @PartType annotation to specify what media type each part is. Here's an example of sending back a list of customers back to a client. The customers are JAXB objects @Path("/multipart") public class MyService { @GET @Produces("multipart/form-data") @PartType("application/xml") public Map get() { ... } }