List<String> l = fileStorage.handleUpload(contentType, content, myIDGenerator, rootPath);
Map<String, List<String>> m = new HashMap<String, List<String>>();
m.put("files", l);
DataFormat outputFormat = new MapJSONFormat();
resp.setEntity(outputFormat.toRepresentation(m));
resp.setStatus(Status.SUCCESS_CREATED);
if (l.size() == 1) {
resp.setRedirectRef(new Reference(req.getResourceRef(), l.get(0)));
}