google app engine URLFetchTransport error while uploading file

Question

During image upload, I'm using below method getBlobKey to get BlobKey for image and saving it's detail in database.

private BlobKey getBlobKey(byte[] data, String fileName) {
        System.out.println("Inside getBlobKey....");
        GcsService gcsService = null;
        GcsFilename gcsFilename = null;
        String bucket = "nirantGallery";

        fileName = fileName + "_" + UUID.randomUUID().toString();

        try {
            gcsService = GcsServiceFactory.createGcsService();
            gcsFilename = new GcsFilename(bucket, fileName);
            GcsFileOptions.Builder options_builder = new GcsFileOptions.Builder();
            options_builder = options_builder.mimeType("image/jpeg");

            GcsFileOptions options = options_builder.build();
            GcsOutputChannel output = GcsServiceFactory.createGcsService().createOrReplace(gcsFilename, options);
            output.write(ByteBuffer.wrap(data));
            output.close();

            // Get serving url
            String gs_blob_key = "/gs/" + bucket + "/" + fileName;
            BlobKey blob_key = BlobstoreServiceFactory.getBlobstoreService().createGsBlobKey(gs_blob_key);
            ServingUrlOptions serving_options = ServingUrlOptions.Builder.withBlobKey(blob_key);
            String serving_url = ImagesServiceFactory.getImagesService().getServingUrl(serving_options);
            System.out.println("Serving URL: " + serving_url);

            return blob_key;
        } catch (Exception e) {
            System.out.println("Inside exception....");
            e.printStackTrace();
        } finally {
            gcsService = null;
        }
        return null;
    }

The problem is when I'm running this in local system, it works and gives me localhost URL like

Serving URL: http://127.0.0.1:8888/_ah/img/encoded_gs_key:L2dzL25pcmFudEdhbGxlcnkvaW1hZ2VfMF9kNjlmOGFjMS05ZTUzLTRiNzUtOTI1ZC1hYzU0ZWQzNzJkNDk

But it is not working when I deploy and run, checked log in server found below details.

Error for /nirat-admin-portal/addGallery
java.lang.NoClassDefFoundError: com/google/api/client/extensions/appengine/http/UrlFetchTransport
    at com.google.appengine.tools.cloudstorage.oauth.OauthRawGcsServiceFactory.<clinit>(OauthRawGcsServiceFactory.java:31)
    at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createRawGcsService(GcsServiceFactory.java:59)
    at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createGcsService(GcsServiceFactory.java:44)
    at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createGcsService(GcsServiceFactory.java:40)
    at com.google.appengine.tools.cloudstorage.GcsServiceFactory.createGcsService(GcsServiceFactory.java:75)
    at com.sparks.nirant.datastore.DataStoreService.getBlobKey(DataStoreService.java:207)
    at com.sparks.nirant.datastore.DataStoreService.saveImageMapToDataStore(DataStoreService.java:183)
    at com.sparks.nirant.serviceImpl.AdminServiceImpl.addGallery(AdminServiceImpl.java:121)
    at com.sparks.nirant.server.AdminController.doPost(AdminController.java:297)

please assist.