public String join(String separator) throws JSONException {
        int len = length();
        StringBuffer sb = new StringBuffer();

        for (int i = 0; i < len; i += 1) {
            if (i > 0) {
                sb.append(separator);
            }
            sb.append(JSONObject.valueToString(this.myArrayList.get(i)));
        }
        return sb.toString();
    }