我如何反序列化此JSON

Question

這是我要解析的JSON數據，但在反序列化方面還是一個新手，我想從此JSON數據中獲取以下屬性：

1. AirportCode 。

2. 拉圖杜德 。

3. 經度 。

這是JSON，其中包含兩個Airports列表。

{
    "AirportResource": {
        "Airports": {
            "Airport": [{
                "AirportCode": "AAL",
                "Position": {
                    "Coordinate": {
                        "Latitude": 57.09305556,
                        "Longitude": 9.85
                    }
                },
                "CityCode": "AAL",
                "CountryCode": "DK",
                "LocationType": "Airport",
                "Names": {
                    "Name": [{
                        "@LanguageCode": "xx",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "de",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "ru",
                        "$": "Ольборг"
                    }, {
                        "@LanguageCode": "pt",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "jp",
                        "$": "オールボア"
                    }, {
                        "@LanguageCode": "kr",
                        "$": "올보르그"
                    }, {
                        "@LanguageCode": "en",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "it",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "fr",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "es",
                        "$": "Aalborg"
                    }, {
                        "@LanguageCode": "ka",
                        "$": "奧爾堡"
                    }, {
                        "@LanguageCode": "pl",
                        "$": "Aalbork"
                    }, {
                        "@LanguageCode": "mi",
                        "$": "奧爾堡"
                    }]
                },
                "UtcOffset": 2,
                "TimeZoneId": "Europe\/Copenhagen"
            }, {
                "AirportCode": "AAR",
                "Position": {
                    "Coordinate": {
                        "Latitude": 56.30388889,
                        "Longitude": 10.62
                    }
                },
                "CityCode": "AAR",
                "CountryCode": "DK",
                "LocationType": "Airport",
                "Names": {
                    "Name": [{
                        "@LanguageCode": "xx",
                        "$": "Aarhus"
                    }, {
                        "@LanguageCode": "en",
                        "$": "Aarhus"
                    }, {
                        "@LanguageCode": "de",
                        "$": "Aarhus"
                    }, {
                        "@LanguageCode": "it",
                        "$": "Aarhus"
                    }, {
                        "@LanguageCode": "fr",
                        "$": "Aarhus"
                    }, {
                        "@LanguageCode": "es",
                        "$": "Aarhus"
                    }]
                },
                "UtcOffset": 2,
                "TimeZoneId": "Europe\/Copenhagen"
            }]
        },
        "Meta": {
            "@Version": "1.0.0",
            "Link": [{
                "@Href": "https:\/\/api.lufthansa.com\/v1\/references\/airports\/?limit=2&LHoperated=0&offset=0",
                "@Rel": "self"
            }, {
                "@Href": "https:\/\/api.lufthansa.com\/v1\/references\/airports\/?limit=2&LHoperated=0&offset=2",
                "@Rel": "next"
            }, {
                "@Href": "https:\/\/api.lufthansa.com\/v1\/references\/airports\/?limit=2&LHoperated=0&offset=1260",
                "@Rel": "last"
            }, {
                "@Href": "https:\/\/api.lufthansa.com\/v1\/references\/cities\/{cityCode}",
                "@Rel": "related"
            }, {
                "@Href": "https:\/\/api.lufthansa.com\/v1\/references\/countries\/{countryCode}",
                "@Rel": "related"
            }],
            "TotalCount": 1261
        }
    }
}

然后我的Java代碼 ：編輯：

private void parseJson(String  result)
    {
        try {
            if (result!=null) {
JSONObject obj = new JSONObject(result).getJSONObject("AirportResource").getJSONObject("Airports");
                JSONArray arr = obj.getJSONArray("Airport");
                for (int i = 0; i < arr.length(); i++)
                {
                    String AirportCode = arr.getJSONObject(i).getString("AAL");
                    String Latitude = arr.getJSONObject(i).getJSONObject("Position").getJSONObject("Coordinate").getString("Latitude");
                    String Longitude =  arr.getJSONObject(i).getJSONObject("Position").getJSONObject("Coordinate").getString("Longitude");
                    System.out.println("Airport : " + AirportCode + " Latitude:  " + Latitude+
                            " Longitude : " + Longitude );
                }

            }
            else{
                Toast.makeText(MainActivity.this,Config.POOR_NETWORK_CONNECTION, Toast.LENGTH_LONG).show();

            }
        }
        catch (JSONException r){
            System.out.println("ERROR PROB : "+  r);

        }
    }

出現的異常是：

org.json.JSONException: No value for AirportResource

如何解析這種JSON數據？

Answer 1

你沒有把機場的對象。 機場內部對象是機場數組，您可以直接訪問它。 因此拋出錯誤。

JSONObject obj2 = obj.getJSONObject("Airports");

現在從obj獲取Json Array

JsonArray jsonarray= obj2.getJsonArray("Airport");

現在在jsonarray的長度上使用for循環。

Answer 2

這將使您入門。

private static void parseJson(JSONObject object) throws JSONException {
    if (object!=null) {
        JSONObject airportResource = object.getJSONObject("AirportResource");
        JSONObject airports = airportResource.getJSONObject("Airports");
        JSONArray airportArray = airports.getJSONArray("Airport");

        for (int i = 0 ; i < airportArray.length(); i++) {
            JSONObject airport = (JSONObject) airportArray.get(i);

            //System.out.println(airport);

            System.out.println("CityCode: " + airport.getString("CityCode"));
        }

    }
    else{
        //null

    }
}

輸出將是：

城市代碼：AAL

城市代碼：AAR

Answer 3

我建議使用此工具來正確查看和格式化JSON。

這是結果

從這里您可以輕松解決問題

JSONObject AirportResource= obj.getJSONObject("AirportResource");
JsonArray AirPorts= AirportResource.getJSONObject("Airports");
JsonArray jsonarray= AirPorts.getJsonArray("Airport");

      for (int i = 0; i < jsonarray.length(); i++) {
        JSONObject obj= AirportResource.get(i); do sth with it
        obj.getString("key"); //do sth with it
       }