How to convert JSONObject to new Map for all its keys using iterator java

Question

I have a JSONObject

{"2016":{"12":{"20":{"19":{"DonationTime":11111111111,"Donation":10}}}}}

I want to convert it to new map with each keys

int i = 0;
for (Iterator<String> keysItr = object.keySet().iterator(); keysItr.`hasNext(); i++) {
            String key = keysItr.next();
            Object value = object.get(key);

            if(value instanceof JSONObject) {
                value = toMap((JSONObject) value);

                map.put(key, value);
            }

        }

        SOP(map);   //but here i want to get 4 maps
    }

I want to get 4 maps like

hourMap[19] = "{"DonationTime":11111111111,"Donation":10}";
dayMap[20] = "{"19":{"DonationTime":11111111111,"Donation":10}}";
monthMap[12] = "{"12":{"20":{"19":{"DonationTime":11111111111,"Donation":10}}}";
yearMap[2016] = "{"12":{"20":{"19":{"DonationTime":11111111111,"Donation":10}}}";

I am using for loop yet i am unable to get incremented value for i.

score 8 · Accepted Answer · edited May 23 '17 at 12:33

Well u can simply convert the JSON object into a map and then from there u can easily take out the four maps u interested in

here is a simple example

(watch out the code below on a big JSON graph can cause u some problems since it is a recursion based conversion)

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

import java.util.*;

public class JsonMapConverter {

public static void main(String... x) throws Exception {

    String jsonString = "{\"2016\":{\"12\":{\"20\":{\"19\":{\"DonationTime\":11111111111,\"Donation\":10}}}}}";
    JSONObject json  = new JSONObject(jsonString);
    Map<String,Object> yearMap = toMap(json);

    String year =  yearMap.keySet().iterator().next();
    Map<String,Object> monthMap = ((Map<String, Object>) yearMap.get(year));

    String month = monthMap.keySet().iterator().next();
    Map<String,Object> dayMap = (Map<String, Object>) monthMap.get(month);

    String day = dayMap.keySet().iterator().next();
    Map<String,Object> hourMap = (Map<String, Object>) dayMap.get(day);

    System.out.println(yearMap);
    System.out.println(monthMap);
    System.out.println(dayMap);
    System.out.println(hourMap);
}

public static Map<String, Object> toMap(JSONObject object) throws JSONException {
    Map<String, Object> map = new HashMap<String, Object>();

    Iterator<String> keysItr = object.keys();
    while(keysItr.hasNext()) {
        String key = keysItr.next();
        Object value = object.get(key);

        if(value instanceof JSONArray) {
            value = toList((JSONArray) value);
        }

        else if(value instanceof JSONObject) {
            value = toMap((JSONObject) value);
        }
        map.put(key, value);
    }
    return map;
}

public static List<Object> toList(JSONArray array) throws JSONException {
    List<Object> list = new ArrayList<Object>();
    for(int i = 0; i < array.length(); i++) {
        Object value = array.get(i);
        if(value instanceof JSONArray) {
            value = toList((JSONArray) value);
        }

        else if(value instanceof JSONObject) {
            value = toMap((JSONObject) value);
        }
        list.add(value);
    }
    return list;
  }
}

for JSON to map conversion i use the code from this answer (Convert a JSON String to a HashMap)

the code was written based on the json string, u may adjust the code according to your needs in case of multiple years,month and days presents in the json

How to convert JSONObject to new Map for all its keys using iterator java

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