导航在Json(Java)

Question

我不熟悉JSON所以如果我使用错误的术语,抱歉.

所以我有这个网址:

 final String PRICE_TRY_URL = "https://api.coindesk.com/v1/bpi/currentprice/try.json";

它返回如下内容:

格式化的JSON数据

{  
   "time":{  },
   "disclaimer":"This data was produced from the CoinDesk Bitcoin Price Index (USD). Non-USD currency data converted using hourly conversion rate from openexchangerates.org",
   "bpi":{  
      "USD":{  
         "code":"USD",
         "rate":"6,911.7500",
         "description":"United States Dollar",
         "rate_float":6911.75
      },
      "TRY":{  
         "code":"TRY",
         "rate":"35,738.0058",
         "description":"Turkish Lira",
         "rate_float":35738.0058
      }
   }
}

我想做的就是达到TRY的价格.我用下面的代码得到了这些数据.

public void doNetworking(){
        AsyncHttpClient client=new AsyncHttpClient();
        client.get(PRICE_TRY_URL, new AsyncHttpResponseHandler() {

                    @Override
                    public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                        Log.d("BitcoinTracker","Succes in doNetworking");
                        // byte[] responseBody can be parsed to a json object.
                        parseJson(responseBody);
                    }

                    @Override
                    public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable error) {
                        Log.e("BitcoinTracker", "Fail " + error.toString());
                    }
                }
        );

这是我的方法:

public void parseJson(byte[] responseBody){
        try {
            JSONObject bitcoinJson  =new JSONObject(new String(responseBody));
            String currency=  bitcoinJson.getString("bpi");
            Log.d("bitcoinmanager",currency);

        } catch (JSONException e) {
            Log.d("BitcoinPrice","BitcoinPriceManager onSucces converting json from byte[] failed.");
            e.printStackTrace();
        }
    }

如上所示,我使用以下语句:

String currency=  bitcoinJson.getString("bpi");

有了这个陈述,我无法达到目标点,即TRY的汇率.如何在JSON格式的文本中导航？

注意:我添加获取JSON数据部分以确保我的问题是明确的,希望它不是太多.

Answer 1

如果您使用的是Android,则无需使用任何外部功能:

JSONObject bitcoinJson = new JSONObject(responseBody);
JSONObject bpi = bitcoinJson.getJSONObject("bpi");
JSONObject tr = bpi.getJSONObject("TRY");
String rate = tr.getString("rate");

使用该org.json.simple库的原始答案,在问题被标记为Android之前:

JSONObject bitcoinJson = (JSONObject)new JSONParser().parse(new String(responseBody));
JSONObject bpi = (JSONObject)bitcoinJson.get("bpi");
JSONObject tr = (JSONObject)bpi.get("TRY");
String rate = (String)tr.get("rate");

请注意,不是构造一个字符串来传递给它JSONParser,而是让它Reader直接访问它更有效.