private JSONObject renderCompute(String service_id, ServiceComponent sc, Integer index)
      throws JSONEncodingException {
    JSONObject json = new JSONObject();
    try {
      json.put(KIND_TAG, KIND);

      JSONObject attrs = new JSONObject();
      setAttribute(ServiceComponent.OCCI_COMPUTE_ARCHITECTURE, attrs, sc.getArchitecture());
      setAttribute(ServiceComponent.OCCI_COMPUTE_CORES, attrs, sc.getCores());
      setAttribute(ServiceComponent.OCCI_COMPUTE_MEMORY, attrs, sc.getMemory());
      setAttribute(ServiceComponent.OCCI_COMPUTE_SPEED, attrs, sc.getSpeed());
      setAttribute(ServiceComponent.OPTIMIS_VM_IMAGE, attrs, sc.getImage());
      setAttribute(ServiceComponent.OPTIMIS_SERVICE_ID, attrs, service_id);
      json.put(ATTRIBUTES_TAG, attrs);
      json.put(ID_TAG, ID_PREFIX + index.toString());
    } catch (JSONException e) {
      throw new JSONEncodingException(
          "There was an error while trying to convert a "
              + "ServiceComponent object into a JSON object");
    }
    return json;
  }
  public static void main(String[] args) {

    OCCI_RestClient cl = new OCCI_RestClient("", "", "");

    List<ServiceComponent> scs = new ArrayList<ServiceComponent>();
    ServiceComponent c1 = new ServiceComponent();
    c1.setArchitecture("x86");
    c1.setCores(2);
    c1.setMemory(2.5);
    c1.setSpeed(0.6);
    c1.setImage("image");
    c1.setInstances(2);
    scs.add(c1);

    try {
      JSONObject obj = cl.renderCompute("a", c1, 1);
      System.out.println(obj.toString(1));
    } catch (Exception e) {
      e.printStackTrace();
    }
  }