Parsing JSON string in Java

user_819916 0
Viewed 429486

I am trying to parse a JSON string in java to have the individual value printed separately. But while making the program run I get the following error-

Exception in thread "main" java.lang.RuntimeException: Stub!
       at org.json.JSONObject.<init>(JSONObject.java:7)
       at ShowActivity.main(ShowActivity.java:29)

My Class looks like- 

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

public class ShowActivity {
   private final static String  jString = "{" 
   + "    \"geodata\": [" 
   + "        {" 
   + "                \"id\": \"1\"," 
   + "                \"name\": \"Julie Sherman\","                  
   + "                \"gender\" : \"female\"," 
   + "                \"latitude\" : \"37.33774833333334\"," 
   + "                \"longitude\" : \"-121.88670166666667\""            
   + "                }" 
   + "        }," 
   + "        {" 
   + "                \"id\": \"2\"," 
   + "                \"name\": \"Johnny Depp\","          
   + "                \"gender\" : \"male\"," 
   + "                \"latitude\" : \"37.336453\"," 
   + "                \"longitude\" : \"-121.884985\""            
   + "                }" 
   + "        }" 
   + "    ]" 
   + "}"; 
   private static JSONObject jObject = null;

   public static void main(String[] args) throws JSONException {
       jObject = new JSONObject(jString);
       JSONObject geoObject = jObject.getJSONObject("geodata");

       String geoId = geoObject.getString("id");
           System.out.println(geoId);

       String name = geoObject.getString("name");
       System.out.println(name);

       String gender=geoObject.getString("gender");
       System.out.println(gender);

       String lat=geoObject.getString("latitude");
       System.out.println(lat);

       String longit =geoObject.getString("longitude");
       System.out.println(longit);                   
   }
}

Let me know what is it I am missing, or the reason why I do get that error everytime I run the application. Any comments would be appreciated.

parsing json java
7 Answers

To convert your JSON string to hashmap you can make use of this : 

HashMap<String, Object> hashMap = new HashMap<>(Utility.jsonToMap(response)) ;

Use this class :) (handles even lists , nested lists and json)

public class Utility {

    public static Map<String, Object> jsonToMap(Object json) throws JSONException {

        if(json instanceof JSONObject)
            return _jsonToMap_((JSONObject)json) ;

        else if (json instanceof String)
        {
            JSONObject jsonObject = new JSONObject((String)json) ;
            return _jsonToMap_(jsonObject) ;
        }
        return null ;
    }


   private static Map<String, Object> _jsonToMap_(JSONObject json) throws JSONException {
        Map<String, Object> retMap = new HashMap<String, Object>();

        if(json != JSONObject.NULL) {
            retMap = toMap(json);
        }
        return retMap;
    }


    private 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;
    }
}
user_66655680

credit to this blog This answer may help someone whose requirements are different.

This is your Json string

 {
"pageNumber":20,
"pageTitle":"example page title",
"pageInfo": {
        "pageName": "Homepage",
        "logo": "https://www.example.com/logo.jpg"
},
"posts": [
        {
            "post_id": "0123456789",
            "actor_id": "1001",
            "author_name": "Jane Doe",
            "post_title": "How to parse JSON in Java",
            "comments": [],
            "time_of_post": "1234567890"
        }
]

}

and this is how to read it

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

 public class ParseJSON {
 static String json = "...";
 public static void main(String[] args) {

    JSONObject obj = new JSONObject(json);
    String pageTitle = obj.getString("pageTitle");
    String pageNumber= obj.getInt("pageNumber");
    String pageName =      obj.getJSONObject("pageInfo").getString("pageName");

    System.out.println(pageNumber);
    System.out.println(pageTitle );
    System.out.println(pageName);

    JSONArray arr = obj.getJSONArray("posts");
    for (int i = 0; i < arr.length(); i++) {
        String post_id = arr.getJSONObject(i).getString("post_id");
        System.out.println(post_id);
    }
}

}

user_65556980
Related