public String toJSON()
  {
    Map<String,String> parameters = new LinkedHashMap<String,String>();
    if (GoCoin.hasValue(getId()))
    {
      parameters.put("id",getId());
    }
    if (GoCoin.hasValue(getFirstName()))
    {
      parameters.put("first_name",getFirstName());
    }
    if (GoCoin.hasValue(getLastName()))
    {
      parameters.put("last_name",getLastName());
    }
    if (GoCoin.hasValue(getEmail()))
    {
      parameters.put("email",getEmail());
    }
    if (GoCoin.hasValue(getImageURL()))
    {
      parameters.put("image_url",getImageURL().toString());
    }
    parameters.put("confirmed",String.valueOf(getConfirmed()));
    if (GoCoin.hasValue(getMerchantId()))
    {
      parameters.put("merchant_id",getMerchantId().toString());
    }
    return GoCoin.toJSON(parameters);
  }