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JSONObject parse dictionary objects

JSON values that I get from server:
{
"Status":0,
"Message":"",
"Result":{"0B":"S.C. Blue Air","0Y":"FlyYeti","1X":"Branson Air"}
}
Getting the result as 'response' after connection and I am able to show my JSON string results on the screen.
JSONObject json = new JSONObject(response);
String status = json.getString("Status");
String message = json.getString("Message");
String result = json.getString("Result");
responseView.setText("Status" + status+ "Message" + message" + Result" + result);
I am okay the results of "Status" and "Message" but not with "Result" because want to separate "Result" objects as and able use each of them as objects.
For example:
When I type OB in my app, I will get the result S.C. Blue Air

Instead of :
String result = json.getString("Result");
use
if(json.get("Result") instanceof JSONObject){
JSONObject object = (JSONObject) json.get("Result");
//do what you want with JSONObject
String ob = object.get("0B");
}
If you want to store it some way you can put it to Map or create object if always it is same data

You can use some libraries such as Gson (Google) or Moshi (Square)
Those libraries allows you to declare your model as a plain java class (commonly called POJOS) annotated in some way that this libraries bind your properties in the JSON to your java properties.
In your case:
JSON:
{
"Status":0,
"Message":"",
"Result":{"0B":"S.C. Blue Air","0Y":"FlyYeti","1X":"Branson Air"}
}
MODEL:
public class MyCallResponse {
#SerializedName("Status")
int status;
#SerializedName("Message")
String message;
#SerializedName("Result")
Result result;
}
public class Result {
#SerializedName("0B")
String b;
#SerializedName("0Y")
String y;
#SerializedName("0X")
String x;
}
In this case, with Gson you can do:
MyCallResponse response = new Gson().fromJson(json, MyCallResponse.class);
Log.i("Response b", response.result.b);
Look at the documentation for more information about both libraries.

try this :
JSONObject json = new JSONObject(response);
JSONObject resultObj = json.getJSONObject("Result");
String OB = resultObj.getString("OB");

Try this
String base = ""; //Your json string;
JSONObject json = new JSONObject(base);
JSONOBject resultJson = json.getJSONObject("Result");
// Get all json keys "OB", "OY", "1X" etc in Result, so that we can get values against each key.
Set<Map.Entry<String, JsonElement>> entrySet = resultJson.entrySet();
Iterator iterator = entrySet.iterator();
for (int j = 0; j < entrySet.size(); j++) {
String key = null; //key = "OB", "OY", "1X" etc
try {
Map.Entry entry = (Map.Entry) iterator.next ();
key = entry.getKey ().toString ();
//key = "OB", "OY", "1X" etc
}
catch (NoSuchElementException e) {
e.printStackTrace ();
}
if (!TextUtils.isEmpty (key)) {
Log.d ("JSON_KEY", key);
String value = resultJson.getString(key);
//for key = "0B", value = "S.C. Blue Air"
//for key = "0Y", value = "FlyYeti"
//for key = "1X", value = "Branson Air"
}
}
It works with any array with dynamic json key.
Don't forget to accept the answer & upvote if it works.

How to modify the JSON data and return the updated JSON data

We have a requirement to update the JSON data in middle and need to return the updated JSON data using java. Also it should support any type of JSON data.
ex:
Assume {object:{"color":"red","shape":"Triangle"}} is the JSON data and in this we need to update the shape value to Rectangle and we need to return the updated JSON data as below:
{object:{"color":"red","shape":"Rectangle"}}
For this we need to pass the element path ( which element we need to update) and updateText and JSON Data to the JAVA code.
here is the methodCall:
updateValue("object/shape", "Rectangle", "{object:{"color":"red","shape":"Triangle"}}")
We tried below code using Gson library. But with this code we are able to update the targeted Json element, but the requirement is to return the entire JSON data with the updated value.
So please suggest how do we re-build the JSON data with the updated text.
Below is the code we tried to update the Json Data.
public String updateValue(String keyPath, String updateText, String jsonText) {
String[] keys = keyPath.split("/");
JsonParser jsonParser = new JsonParser();
JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonText);
String result = "";
for(String key : keys)
{
if (jsonObject.get(key) instanceof JsonObject)
{
jsonObject = (JsonObject)jsonObject.get(key);
}
else if(jsonObject.get(key) instanceof JsonArray)
{
JsonArray jsonArray = (JsonArray)jsonObject.get(key);
result = jsonArray.toString();
}
else
{
result = jsonObject.get(key).toString();
}
}
result = result.replace(result, updateText);
return result;
}

The problem lies in the way you do the replacements. When you translate the JsonObject to String, you lose the object, and after replacement, you just have the replaced String. To fix it, you need to operate directly on the object, instead of the String counterpart. Because JsonObject is mutable, holding a reference to the input will reflect the changes. One drawback is you can't replace a value in a JsonArray this way, partly because you don't know which element to replace. To accomplish that, you will need a little more in the input(either the value to replace or the element position).
public String updateValue(String keyPath, String updateText, String jsonText) {
String[] keys = keyPath.split("/");
JsonParser jsonParser = new JsonParser();
JsonObject jsonObject = (JsonObject) jsonParser.parse(jsonText);
JsonObject returnVal = jsonObject; // This holds the ref to target json object
JsonPrimitive jp = new JsonPrimitive(updateText);
String finalKey = keys[keys.length - 1];
for(String key : keys)
{
if (jsonObject.get(key).isJsonObject())
{
jsonObject = (JsonObject)jsonObject.get(key);
}
}
jsonObject.remove(finalKey);
jsonObject.add(finalKey, jp);
return returnVal.toString();
}

You can use JsonPath lib for that and try using the following code.
private static final Configuration configuration = Configuration.builder()
.jsonProvider(new JacksonJsonNodeJsonProvider())
.mappingProvider(new JacksonMappingProvider())
.build();
JsonNode updatedJson = JsonPath.using(configuration).parse(originaljson)
.set("use the path to go for value", "new value").json();
json = updatedJson.toString();

How to get specific JSON data?

Hi I am trying to read JSON from an ReST API but Im getting a nullpointer exception because mycode is not correct.
I have a JSON that I am reading from looking like this :
processJSON({
"LocationList":{
"noNamespaceSchemaLocation":"http://api.vasttrafik.se/v1/hafasRestLocation.xsd",
"servertime":"16:13",
"serverdate":"2013-03-22",
"StopLocation":[{
"name":"Brunnsparken, Göteborg",
"lon":"11.967824",
"lat":"57.706944",
"id":"9021014001760000",
"idx":"1"
},{
"name":"Brunnsgatan, Göteborg",
"lon":"11.959455",
"lat":"57.693766",
"id":"9021014001745000",
"idx":"4"
},{
"name":"Brunnslyckan, Lerum",
"lon":"12.410219",
"lat":"57.812073",
"id":"9021014017260000",
"idx":"5"
},
Now I want the name from the JSON document depending on what the user inputs.
how do I do this with code?
My code that is wrong is like this :
import org.json.simple.JSONObject;
import org.json.simple.JSONValue;
public class JSONReader {
private String jsonData = "";
public String getJsonData(String location){
try {
URL url = new URL("http://api.vasttrafik.se/bin/rest.exe/v1/location.name?authKey=secret&format=json&jsonpCallback=processJSON&input=" + URLEncoder.encode(location, "UTF-8"));
URLConnection connection = url.openConnection();
BufferedReader readJsonFile = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
String temp = "";
while((temp = readJsonFile.readLine()) != null){
jsonData += temp;
}
readJsonFile.close();
System.out.println(jsonData);
return jsonData;
}
catch (IOException e) {
}
return null;
}
public void JSONParsing(){
String location = Planner.getPlanner().getStartingLocation();
JSONObject obj =(JSONObject)JSONValue.parse(getJsonData(location));
//Set the text into the JList
if (obj.containsValue(location));
obj.get("name");
}
}
I want get the same name of the location out from the JSON as the user inputs.
How do I do this with code?

I think that you are asking how to parse your JSONObject and get the corresponding values out of it that the user is interested in. Below is an example of how you can pull apart the JSONObject to create a Map whose key is the String id (since the name does not seem to be unique) and whose value is the whole JSONObject. You can use this map to lookup the input from the user and find the appropriate LLA if that's what you are interested in.
public Map<String, JSONObject> createLocationMap(JSONObject jsonObj){
Map<String, JSONObject> nameToLocationMap = new HashMap<String, JSONObject>();
JSONObject locationList = (JSONObject) jsonObj.get("LocationList");
JSONArray array = (JSONArray) locationList.get("StopLocation");
for (int i = 0; i < array.length(); i++) {
String name = (String) ((JSONObject) array.get(i)).get("id");
nameToLocationMap.put(name, ((JSONObject)array.get(i)));
}
return nameToLocationMap;
}
You can tailor this method as you see fit. For example if you are interested in the relationship between the id and the name then you can create a similar method that uses those values instead of id and the entire JSONObject'. I hope that this helps~

JSON Object is null while parsing

The format of my json object is:
String jsonObjRecv = {
"response":{
"respobj":{
"id":<int>,
"number":<string>,
"validated":<boolean>
}
},
"status":"ok",
"errors":null
}
It works when code is:
JSONObject jsonObjCont = new JSONObject(jsonObjRecv);
String getString= jsonObjCont.toString(2);
In this case getString != null and I can receive data, but when I try to get nested data of JSON object as like:
JSONObject jsonObjCont = new JSONObject(jsonObjRecv);
JSONObject regNumber = jsonObjCont.getJSONObject("respobj");
String number= regNumber.getString("number");
it dont work.
I tried to use GSON library, but it works when:
public String parse(String jsonObjRecv) {
JsonElement jelement = new JsonParser().parse(jsonObjRecv);
String result = jelement.toString();
return result;
and don't work :
public String parse(String jsonObjRecv) {
JsonElement jelement = new JsonParser().parse(jsonObjRecv);
JsonObject jobject = jelement.getAsJsonObject();
jobject = jobject.getAsJsonObject("respobj");
String result = jobject.get("number").toString();
return result;
Where is my mistake?

The problem is you're not accessing your JSON object correctly - it's an object that contains a response object which contains a respobj object.
Gson example follows. Note the comment in the code - you need to get the response object then get the respobj from it.
public static void main( String[] args )
{
String jsonObjRecv = "{\"response\":{\"respobj\":{\"id\":1,\"number\":\"22\",\"validated\":true}},\"status\":\"ok\",\"errors\":null}";
JsonElement jelement = new JsonParser().parse(jsonObjRecv);
JsonObject jobject = jelement.getAsJsonObject();
// Here is where you're making an error. You need to get the outer
// 'response' object first, then get 'respobj' from that.
jobject = jobject.getAsJsonObject("response").getAsJsonObject("respobj");
String result = jobject.get("number").getAsString();
System.out.println(result);
}
Output:
22
Edit to add: Note I used getAsString() vs. toString() - if you use the latter you get the raw JSON which will incluse the quotes around the value (e.g. the output would be "22")

Json conversion

i want to create a Json like this
[{"sID":"221","mID":"0"},
{"sID":"222","mID":"11"},
{"sID":"223","mID":"11"}]
i have tried below code but that create Json just only for one line
JSONObject json = new JSONObject();
JSONObject manJson = new JSONObject();
manJson.put("sID", "23");
manJson.put("mID", "111");
json.put("",manJson);
this above code create Json like this
{"":{"sID":"23","mID":"111"}}
Please let me know about the changes required in that Java code thanks.

Change your code as:
JSONArray jsonArray = new JSONArray();
//Add 1st JSONObject to JSONArray
JSONObject jsonObjone = new JSONObject();
jsonObjone.put("sID", "221");
jsonObjone.put("mID","0");
jsonArray.put(jsonObjone.toString();
//Add 2nd JSONObject to JSONArray
JSONObject jsonObjtwo = new JSONObject();
jsonObjtwo.put("sID", "222");
jsonObjtwo.put("mID","11");
jsonArray.put(jsonObjtwo.toString());
//Add 3rd JSONObject to JSONArray
JSONObject jsonObjthrd = new JSONObject();
jsonObjthrd.put("sID", "223");
jsonObjthrd.put("mID","11");
jsonArray.put(jsonObjthrd.toString());

Use toJSONArray() method on manjson.

I recommend the jackson library it makes things very easy. To use it you would have an object like this...
class Ids {
private int Sid;
private int Mid;
public setSid(int Sid) {
this.Sid = Sid;
}
public setMid(int Mid) {
this.Mid = Mid;
}
public getSid() {
return Sid;
}
public getMid() {
return Mid;
}
}
Then you can use the objectMapper from the library to go from an array that you have in memory to a json String like so
Ids[] idsArray = new Ids[2];
//add ids object to array
String jsonString = objectMapper.writeValueAsString(idsArray);
Of course doing it this way depends on how your ids are stored but for me it generally makes my code a lot cleaner and the Jackson Library is pretty good performance wise.