JSON解析：一键，多值

Question

I'm having a little bit of trouble with how to parse the following data:

[{
    "Name": "EB DAVIE ST FS HOWE ST",
    "Latitude": 49.27755,
    "Longitude": -123.12698,
    "Routes": "006, C23"   }]

I would like to get all the values of "Routes". Then I would like to create a new "Route" from each string, and store each "Route" in a set. But I'm not sure how to iterate over it.. (for this example, we can just say that each Route has just a name).

So far I have:

        JSONObject stop = allStops.getJSONObject(i);
        JSONArray array = stop.getJSONArray("Routes");

        for(int i = 0; i < array.length(); i++) {
        Route r = new Route(array.get(i))   // i thought (array.get(i)) would give you the String of each value (e.g. "006")
        Set<Route> routes = new HashSet<Route>();
        routes.add(array.get(i));   // then I thought I should just add each route
}

but this doesn't work. I'm not sure what to do.

Answer 1

String routes = stop.getString("Routes");
String[] split_routes = routes.split(", "); /*all routes will be stored in this array*/

Answer 2

你可以尝试使用com.alibaba.fastjson.JSON，定义一个java类，然后像这样：

List<MyClass> list= JSON.parseObject(jsonStr, new TypeReference<List<MyClass>>() {});

Answer 3

I just modified your code, this will parse your specified JSON format,

import org.json.JSONArray;
import org.json.JSONObject;

public class JsonParser {

    public static void main(String[] args) throws Exception {

        String jsonString = "[{\"Name\":\"EB DAVIE ST FS HOWE ST\",\"Latitude\":49.27755,\"Longitude\":-123.12698,\"Routes\":\"006, C23\"}]";
        JSONArray arrayObject = new JSONArray(jsonString);
        JSONObject inner = arrayObject.getJSONObject(0);
        String[] keys = JSONObject.getNames(inner);

        for(String entry : keys) {
            System.out.println(entry+" : "+inner.get(entry));
        }

    }
}

• Initially we are converting the json string to JSONArray object.
• Then we are parsing the JSONObject from the JSONArray . Here we have only one JSONObject so we used getJSONObject(0) . If you have more than one JSONObject you can iterate the values using a loop.
• Then we are storing all the key values within the JSONObject in a String Array.
• Finally we are iterating the values for the keys.

Output:

Latitude : 49.27755
Routes : 006, C23
Longitude : -123.12698
Name : EB DAVIE ST FS HOWE ST