为什么我得到“ java.lang.String无法转换为JSONObject”

Question

为什么会出现错误

  

“ java.lang.String类型的值SAMPLE_JSON_RESPONSE不能为   转换为JSONObject”

我认为我必须格式化SAMPLE_JSON_RESPONSE，如果可以，请告诉我该怎么做？

private static final String SAMPLE_JSON_RESPONSE = "{\"type\":\"FeatureCollection\",\"metadata\":{\"generated\":1462295443000,\"url\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&starttime=2016-01-01&endtime=2016-01-31&minmag=6&limit=10\",\"title\":\"USGS Earthquakes\",\"status\":200,\"api\":\"1.5.2\",\"limit\":10,\"offset\":1,\"count\":10},\"features\":[{\"type\":\"Feature\",\"properties\":{\"mag\":7.2,\"place\":\"88km N of Yelizovo, Russia\",\"time\":1454124312220,\"updated\":1460674294040,\"tz\":720,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us20004vvx\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us20004vvx&format=geojson\",\"felt\":2,\"cdi\":3.4,\"mmi\":5.82,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":798,\"net\":\"us\",\"code\":\"20004vvx\",\"ids\":\",at00o1qxho,pt16030050,us20004vvx,gcmt20160130032510,\",\"sources\":\",at,pt,us,gcmt,\",\"types\":\",cap,dyfi,finite-fault,general-link,general-text,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":0.958,\"rms\":1.19,\"gap\":17,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 7.2 - 88km N of Yelizovo, Russia\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[158.5463,53.9776,177]},\"id\":\"us20004vvx\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.1,\"place\":\"94km SSE of Taron, Papua New Guinea\",\"time\":1453777820750,\"updated\":1460156775040,\"tz\":600,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us20004uks\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us20004uks&format=geojson\",\"felt\":null,\"cdi\":null,\"mmi\":4.1,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":572,\"net\":\"us\",\"code\":\"20004uks\",\"ids\":\",us20004uks,gcmt20160126031023,\",\"sources\":\",us,gcmt,\",\"types\":\",cap,geoserve,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":1.537,\"rms\":0.74,\"gap\":25,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.1 - 94km SSE of Taron, Papua New Guinea\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[153.2454,-5.2952,26]},\"id\":\"us20004uks\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.3,\"place\":\"50km NNE of Al Hoceima, Morocco\",\"time\":1453695722730,\"updated\":1460156773040,\"tz\":0,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004gy9\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004gy9&format=geojson\",\"felt\":117,\"cdi\":7.2,\"mmi\":5.28,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":0,\"sig\":695,\"net\":\"us\",\"code\":\"10004gy9\",\"ids\":\",us10004gy9,gcmt20160125042203,\",\"sources\":\",us,gcmt,\",\"types\":\",cap,dyfi,geoserve,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":2.201,\"rms\":0.92,\"gap\":20,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.3 - 50km NNE of Al Hoceima, Morocco\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[-3.6818,35.6493,12]},\"id\":\"us10004gy9\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":7.1,\"place\":\"86km E of Old Iliamna, Alaska\",\"time\":1453631430230,\"updated\":1460156770040,\"tz\":-540,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004gqp\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004gqp&format=geojson\",\"felt\":1816,\"cdi\":7.2,\"mmi\":6.6,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":1496,\"net\":\"us\",\"code\":\"10004gqp\",\"ids\":\",at00o1gd6r,us10004gqp,ak12496371,gcmt20160124103030,\",\"sources\":\",at,us,ak,gcmt,\",\"types\":\",cap,dyfi,finite-fault,general-link,general-text,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,trump-origin,\",\"nst\":null,\"dmin\":0.72,\"rms\":2.11,\"gap\":19,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 7.1 - 86km E of Old Iliamna, Alaska\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[-153.4051,59.6363,129]},\"id\":\"us10004gqp\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.6,\"place\":\"215km SW of Tomatlan, Mexico\",\"time\":1453399617650,\"updated\":1459963829040,\"tz\":-420,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004g4l\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004g4l&format=geojson\",\"felt\":11,\"cdi\":2.7,\"mmi\":3.92,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":673,\"net\":\"us\",\"code\":\"10004g4l\",\"ids\":\",at00o1bebo,pt16021050,us10004g4l,gcmt20160121180659,\",\"sources\":\",at,pt,us,gcmt,\",\"types\":\",cap,dyfi,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":2.413,\"rms\":0.98,\"gap\":74,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.6 - 215km SW of Tomatlan, Mexico\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[-106.9337,18.8239,10]},\"id\":\"us10004g4l\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.7,\"place\":\"52km SE of Shizunai, Japan\",\"time\":1452741933640,\"updated\":1459304879040,\"tz\":540,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004ebx\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004ebx&format=geojson\",\"felt\":51,\"cdi\":5.8,\"mmi\":6.45,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":720,\"net\":\"us\",\"code\":\"10004ebx\",\"ids\":\",us10004ebx,pt16014050,at00o0xauk,gcmt20160114032534,\",\"sources\":\",us,pt,at,gcmt,\",\"types\":\",associate,cap,dyfi,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,\",\"nst\":null,\"dmin\":0.281,\"rms\":0.98,\"gap\":22,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.7 - 52km SE of Shizunai, Japan\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[142.781,41.9723,46]},\"id\":\"us10004ebx\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.1,\"place\":\"12km WNW of Charagua, Bolivia\",\"time\":1452741928270,\"updated\":1459304879040,\"tz\":-240,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004ebw\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004ebw&format=geojson\",\"felt\":3,\"cdi\":2.2,\"mmi\":2.21,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":0,\"sig\":573,\"net\":\"us\",\"code\":\"10004ebw\",\"ids\":\",us10004ebw,gcmt20160114032528,\",\"sources\":\",us,gcmt,\",\"types\":\",cap,dyfi,geoserve,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":5.492,\"rms\":1.04,\"gap\":16,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.1 - 12km WNW of Charagua, Bolivia\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[-63.3288,-19.7597,582.56]},\"id\":\"us10004ebw\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.2,\"place\":\"74km NW of Rumoi, Japan\",\"time\":1452532083920,\"updated\":1459304875040,\"tz\":540,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004djn\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004djn&format=geojson\",\"felt\":8,\"cdi\":3.4,\"mmi\":3.74,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":0,\"sig\":594,\"net\":\"us\",\"code\":\"10004djn\",\"ids\":\",us10004djn,gcmt20160111170803,\",\"sources\":\",us,gcmt,\",\"types\":\",cap,dyfi,geoserve,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":1.139,\"rms\":0.96,\"gap\":33,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.2 - 74km NW of Rumoi, Japan\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[141.0867,44.4761,238.81]},\"id\":\"us10004djn\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6.5,\"place\":\"227km SE of Sarangani, Philippines\",\"time\":1452530285900,\"updated\":1459304874040,\"tz\":480,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004dj5\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004dj5&format=geojson\",\"felt\":1,\"cdi\":2.7,\"mmi\":7.5,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":1,\"sig\":650,\"net\":\"us\",\"code\":\"10004dj5\",\"ids\":\",at00o0srjp,pt16011050,us10004dj5,gcmt20160111163807,\",\"sources\":\",at,pt,us,gcmt,\",\"types\":\",cap,dyfi,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\"nst\":null,\"dmin\":3.144,\"rms\":0.72,\"gap\":22,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.5 - 227km SE of Sarangani, Philippines\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[126.8621,3.8965,13]},\"id\":\"us10004dj5\"},\n" +
        "{\"type\":\"Feature\",\"properties\":{\"mag\":6,\"place\":\"Pacific-Antarctic Ridge\",\"time\":1451986454620,\"updated\":1459202978040,\"tz\":-540,\"url\":\"http://Earthquake.usgs.gov/earthquakes/eventpage/us10004bgk\",\"detail\":\"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us10004bgk&format=geojson\",\"felt\":0,\"cdi\":1,\"mmi\":0,\"alert\":\"green\",\"status\":\"reviewed\",\"tsunami\":0,\"sig\":554,\"net\":\"us\",\"code\":\"10004bgk\",\"ids\":\",us10004bgk,gcmt20160105093415,\",\"sources\":\",us,gcmt,\",\"types\":\",cap,dyfi,geoserve,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,\",\"nst\":null,\"dmin\":30.75,\"rms\":0.67,\"gap\":71,\"magType\":\"mww\",\"type\":\"Earthquake\",\"title\":\"M 6.0 - Pacific-Antarctic Ridge\"},\"geometry\":{\"type\":\"Point\",\"coordinates\":[-136.2603,-54.2906,10]},\"id\":\"us10004bgk\"}],\"bbox\":[-153.4051,-54.2906,10,158.5463,59.6363,582.56]}";

private QueryUtils() {

public static ArrayList<Earthquake> extractEarthquakes() {
    ArrayList<Earthquake> earthquakes = new ArrayList<>();
    try {
        JSONObject baseJsonResponse = new JSONObject(SAMPLE_JSON_RESPONSE);
        JSONArray earthquakeArray = baseJsonResponse.getJSONArray("features");

        for (int i = 0; i < earthquakeArray.length(); i++) {

            JSONObject currentEarthquake = earthquakeArray.getJSONObject(i);
            JSONObject properties = currentEarthquake.getJSONObject("properties");
            String magnitude = properties.getString("mag");
            String location = properties.getString("place");

            String time = properties.getString("time");

            Earthquake earthquake = new Earthquake(magnitude, location, time);
            earthquakes.add(earthquake);
        }

    } catch (JSONException e) {

        Log.e("QueryUtils", "Problem parsing the Earthquake JSON results", e);
    }
    return earthquakes;
}

Answer 1

要从字符串创建JSON对象，必须正确地对其进行转义，而当前不是这样

您的帖子中包含很多JSON，因此我以JSON的第一行为例（这是第一个功能对象）。然后，我取消转义JSON，然后验证JSON。有很多工具可以执行此操作，但是我使用https://www.freeformatter.com/json-escape.html进行格式化，并使用https://jsonlint.com/进行JSON验证。我发现JSON对象存在一些问题（新行\ n转义）。然后，我可以通过将其粘贴到Android Studio中来逃脱JSON，如下所示，并且JSON现在将字符串解析为JSONObject。 我建议您这样做并逐行进行，直到您验证了所有JSON，然后将有效的JSON粘贴在引号private static final String SAMPLE_JSON_RESPONSE = "";

之间。

Android Studio（希望其他IDE可以正确转义JSON，否则您将不得不使用JSON转义实用程序）

private static final String SAMPLE_JSON_RESPONSE = "{\n" +
            "\t\"type\": \"FeatureCollection\",\n" +
            "\t\"metadata\": {\n" +
            "\t\t\"generated\": 1462295443000,\n" +
            "\t\t\"url\": \"http://Earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&starttime=2016-01-01&endtime=2016-01-31&minmag=6&limit=10\",\n" +
            "\t\t\"title\": \"USGS Earthquakes\",\n" +
            "\t\t\"status\": 200,\n" +
            "\t\t\"api\": \"1.5.2\",\n" +
            "\t\t\"limit\": 10,\n" +
            "\t\t\"offset\": 1,\n" +
            "\t\t\"count\": 10\n" +
            "\t},\n" +
            "\t\"features\": [{\n" +
            "\t\t\"type\": \"Feature\",\n" +
            "\t\t\"properties\": {\n" +
            "\t\t\t\"mag\": 7.2,\n" +
            "\t\t\t\"place\": \"88km N of Yelizovo, Russia\",\n" +
            "\t\t\t\"time\": 1454124312220,\n" +
            "\t\t\t\"updated\": 1460674294040,\n" +
            "\t\t\t\"tz\": 720,\n" +
            "\t\t\t\"url\": \"http://Earthquake.usgs.gov/earthquakes/eventpage/us20004vvx\",\n" +
            "\t\t\t\"detail\": \"http://Earthquake.usgs.gov/fdsnws/event/1/query?eventid=us20004vvx&format=geojson\",\n" +
            "\t\t\t\"felt\": 2,\n" +
            "\t\t\t\"cdi\": 3.4,\n" +
            "\t\t\t\"mmi\": 5.82,\n" +
            "\t\t\t\"alert\": \"green\",\n" +
            "\t\t\t\"status\": \"reviewed\",\n" +
            "\t\t\t\"tsunami\": 1,\n" +
            "\t\t\t\"sig\": 798,\n" +
            "\t\t\t\"net\": \"us\",\n" +
            "\t\t\t\"code\": \"20004vvx\",\n" +
            "\t\t\t\"ids\": \",at00o1qxho,pt16030050,us20004vvx,gcmt20160130032510,\",\n" +
            "\t\t\t\"sources\": \",at,pt,us,gcmt,\",\n" +
            "\t\t\t\"types\": \",cap,dyfi,finite-fault,general-link,general-text,geoserve,impact-link,impact-text,losspager,moment-tensor,nearby-cities,origin,phase-data,shakemap,tectonic-summary,\",\n" +
            "\t\t\t\"nst\": null,\n" +
            "\t\t\t\"dmin\": 0.958,\n" +
            "\t\t\t\"rms\": 1.19,\n" +
            "\t\t\t\"gap\": 17,\n" +
            "\t\t\t\"magType\": \"mww\",\n" +
            "\t\t\t\"type\": \"Earthquake\",\n" +
            "\t\t\t\"title\": \"M 7.2 - 88km N of Yelizovo, Russia\"\n" +
            "\t\t},\n" +
            "\t\t\"geometry\": {\n" +
            "\t\t\t\"type\": \"Point\",\n" +
            "\t\t\t\"coordinates\": [158.5463, 53.9776, 177]\n" +
            "\t\t},\n" +
            "\t\t\"id\": \"us20004vvx\"\n" +
            "\t}]\n" +
            "}";

    JSONObject baseJsonResponse = new JSONObject(SAMPLE_JSON_RESPONSE);