Java Bitstamp API市场订单文件未找到

Question

我正在尝试使用我的Bitstamp帐户从Java发布市场订单但以下代码返回找不到该URL的文件。

可能是因为CSRF，但我不确定，如果有人对bitstamp API有任何经验，那将是很棒的。

public static void postToken() throws IOException, JSONException {
    URL url = null;
    String sig = encode();
    try {
        url = new URL("https://www.bitstamp.net/api/v2/buy/market/" + feedbackType.toLowerCase() +"usd/");
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setConnectTimeout(5000);//5 secs
        connection.setReadTimeout(5000);//5 secs

        connection.setRequestMethod("POST");
        connection.setDoOutput(true);
        connection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");

        JSONObject cred = new JSONObject();

        cred.put("key",api_key);
        cred.put("signature", sig);
        cred.put("nonce", nonce);
        cred.put("amount", feedback);

        OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream());
        out.write(cred.toString());
        out.flush();
        out.close();

        int res = connection.getResponseCode();
        System.out.println(res);

        InputStream is = connection.getInputStream();
        BufferedReader br = new BufferedReader(new InputStreamReader(is));
        String line = null;
        while((line = br.readLine() ) != null) {
            Log.d(TAG, line);
        }
        connection.disconnect();
    } catch (MalformedURLException e) {
        e.printStackTrace();
    }
}

错误：W / System.err：java.io.FileNotFoundException：https://www.bitstamp.net/api/v2/buy/market/btcusd/