code: public String getAssetURL(String id) {
          String url = getRepositoryUrl() + "/assets/" + id + "?";
          if (getUserId() != null) {
              url += "userId=" + getUserId();
          }
          if (getUserId() != null && getPassword() != null) {
              url += "&password=" + getPassword();
          }
          if (getApiKey() != null) {
              url += "&apiKey=" + getApiKey();
          }
          return url;
      }
docs: Returns a URL which represent the URL that can be used to view the asset in Massive. This is more
  for testing purposes, the assets can be access programatically via various methods on this class.
  
  @param asset - an Asset
  @return String - the asset URL