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How to create multi level JSON data using JSONObject in servlet

I need to create JSON data like below,
{
"min": {
"week": "1",
"year": "2014"
},
"max": {
"week": "14",
"year": "2017"
}
}
But JSONObject accepts only "id","value" format.
So how can I create JSON data using JSONObject like mentioned above.

That is very easy, here is an example:
JSONObject min = new JSONObject();
min.put("week", "1");
min.put("year", "2014");
JSONObject max = new JSONObject();
max.put("week", "14");
max.put("year", "2017");
JSONObject json= new JSONObject();
stats.put("min", min);
stats.put("max", max);
System.out.println(json.toString());

Tested this in eclipse already for you.
`
String s = "{ \"min\": { \"week\": \"1\", \"year\": \"2014\" }, \"max\": { \"week\": \"14\", \"year\": \"2017\" } }";
JSONParser parser = new JSONParser();
try {
JSONObject json = (JSONObject) parser.parse(s);
System.out.println(json.get("min"));
// this will output
//{"week":"1","year":"2014"}
} catch (Exception e){
e.printStackTrace();
}
`

2D JSON Array Not Generated in Correctly Java

I'm trying to generate 2d JSON Array in Java using Json Object, JSON Array. The 2d array being generated is valid but the ordering of elements is wrong.
Java Code...
JSONObject root1 = new JSONObject();
JSONObject c01 = new JSONObject();
JSONObject c11 = new JSONObject();
JSONObject attachment = new JSONObject();
JSONObject payload = new JSONObject();
JSONArray arrayButton= new JSONArray();
JSONArray arrayelements= new JSONArray();
JSONObject elementsObj = new JSONObject();
JSONObject defaultAction = new JSONObject();
root1.put("recipient", c01);
root1.put("message", c11);
c01.put("id", userId);
c11.put("attachment", attachment);
attachment.put("type", "template");
attachment.put("payload", payload);
payload.put("template_type", "generic");
payload.put("elements", arrayelements);
arrayelements.put(elementsObj);
elementsObj.put("title", "Sample Title");
elementsObj.put("image_url", "https://google.com/");
elementsObj.put("subtitle", "Sample Sub Title");
elementsObj.put("default_action", defaultAction);
defaultAction.put("type", "web_url");
defaultAction.put("url", "https://www.google.com/");
defaultAction.put("messenger_extensions", "true");
defaultAction.put("webview_height_ratio", "tall");
defaultAction.put("fallback_url", "https://www.google.com/");
elementsObj.put("buttons", arrayButton);
JSONObject buttons1 = new JSONObject();
buttons1.put("type", "web_url");
buttons1.put("url", "https://google.com");
buttons1.put("title", "show website");
arrayButton.put(buttons1);
JSONObject buttons2 = new JSONObject();
buttons2.put("type", "postback");
buttons2.put("title", "Hi There");
buttons2.put("payload", "sample payload");
arrayButton.put(buttons2);
Expected Output
{
"recipient":{
"id":"USER_ID"
},
"message":{
"attachment":{
"type":"template",
"payload":{
"template_type":"generic",
"elements":[
{
"title":"Sample title",
"image_url":"https://google.com/company_image.png",
"subtitle":"We\'ve got the right hat for everyone.",
"default_action": {
"type": "web_url",
"url": "https://google.com/",
"messenger_extensions": true,
"webview_height_ratio": "tall",
"fallback_url": "https://google.com/"
},
"buttons":[
{
"type":"web_url",
"url":"https://google.com",
"title":"View Website"
},{
"type":"postback",
"title":"Start Chatting",
"payload":"Sample payload"
}
]
}
]
}
}
}
}
Current Output
{
"recipient":{
"id":"988459377921053"
},
"message":{
"attachment":{
"payload":{
"elements":[
{
"buttons":[
{
"type":"web_url",
"title":"show website",
"url":"https://google.com"
},
{
"payload":"sample payload",
"type":"postback",
"title":"Hi There"
}
],
"image_url":"https://s3-ap-southeast-1.amazonaws.com/fls-items-dev/sample-item-4-95/post/sample-item-4-95-primary-4495.png",
"subtitle":"Sample Sub Title",
"title":"Sample Title",
"default_action":{
"fallback_url":"https://www.frrndlease.com/",
"webview_height_ratio":"tall",
"messenger_extensions":"true",
"type":"web_url",
"url":"https://www.frrndlease.com/ItemDetails?uid=wilson-kid-235"
}
}
],
"template_type":"generic"
},
"type":"template"
}
}
}
The order of buttons array, objects template_type & type are inverse. I'm creating nested Json objects and adding them from the outer level to the inner level still the output JSON is not as expected. Can't understand where I'm going wrong.

How to access JSON data with multiple array objects : android

I am stuck in getting the data from the JSON file with multiple data sets.
{
"status": "ok",
"count": 3,
"count_total": 661,
"pages": 133,
"posts": [
{
"id": 20038,
"type": "post",
"slug": "xperia-launcher-download",
"url": "http:\/\/missingtricks.net\/xperia-launcher-download\/",
"status": "publish",
"title": "Download Xperia Launcher app for Android (Latest Version)"
},
{
"id": 94,
"type": "post",
"slug": "top-free-calling-apps-of-2014-year",
"url": "http:\/\/missingtricks.net\/top-free-calling-apps-of-2014-year\/",
"status": "publish",
"title": "Best Free Calling Apps for Android November 2014"
},
{
"id": 98,
"type": "post",
"slug": "top-free-calling-apps-of-2016-year",
"url": "http:\/\/missingtricks.net\/top-free-calling-apps-of-2016-year\/",
"status": "publish",
"title": "Best Free Calling Apps for Android December 2016"
}
]
}
I need to access the title, url and status from the above JSON file.
#Override
protected void onPostExecute(String result) {
//this method will be running on UI thread
pdLoading.dismiss();
List<DataFish> data = new ArrayList<>();
pdLoading.dismiss();
try {
JSONArray jArray = new JSONArray(result);
// Extract data from json and store into ArrayList as class objects
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
DataFish fishData = new DataFish();
fishData.status = json_data.getString("status");
fishData.title = json_data.getString("url");
fishData.sizeName = json_data.getString("title");
data.add(fishData);
}
} catch (JSONException e) {
Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
Log.d("Json","Exception = "+e.toString());
}
}
I am getting a JSONException with the above code.
What should I do to access the title,status and url from the JSON File?

You have to fetch your JSONArray which is inside a JSONObject , so create a JSONObject and fetch your array with index "posts"
1.) result is a JSONObject so create a JSONObject
2.) Fetch your JSONArray with index value as "posts"
3.) Now simply traverse array objects by fetching it through index
JSONObject jObj = new JSONObject(result);
JSONArray jArray = jObj.getJSONArray("posts");
// Extract data from json and store into ArrayList as class objects
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
DataFish fishData = new DataFish();
fishData.status = json_data.getString("status");
fishData.title = json_data.getString("url");
fishData.sizeName = json_data.getString("title");
data.add(fishData);
}
Note : i don't know weather it is a sample response with shorter version though your json object should ends with } not with , .
[{"id":20038,"type":"post","slug":"xperia-launcher-download","url":"http://missingtricks.net/xperia-launcher-download/","status":"publish","title":"Download
Xperia Launcher app for Android (Latest Version)",
// ^^^ there should be a } not a , to end json
// so make sure to do the correction so it will look like => ...st Version)"},
{"id":94,"type":"post","slug":"top-free-calling-apps-of-2014-year","url":"http://missingtricks.net/top-free-calling-apps-of-2014-year/","status":"publish","title":"Best
Free Calling Apps for Android November 2014", ]
Improvements :
you can use optString to avoid null or non-string value if there is no mapping key
This has two variations
Get an optional string associated with a key. It returns the
defaultValue if there is no such key.
public String optString(String key, String defaultValue) {
fishData.status = json_data.optString("status","N/A");
// will return "N/A" if no key found
or To get empty string if no key found then simply use
fishData.status = json_data.optString("status");
// will return "" if no key found where "" is an empty string

You can validate your JSON here.
If entire JSON getJsonObject() is not working, then you should parse JSON objects & array in multiple arrays then use them.

Android - How to parse specific values from JSON Array and display Toast

New to Android and Java in general and I'm learning how to make a JSON call. To do so, I'm following this guide: http://mobiforge.com/design-development/consuming-json-services-android-apps
Here's where things get confusing for me. The author of that tutorial wants the reader to call this API: http://ws.geonames.org/findNearByWeatherJSON?lat=37lng=122
Which returns a JSON object in this format:
{
"weatherObservation": {
"clouds":"scattered clouds",
"weatherCondition":"n/a",
"observation":"KCFV 090852Z AUTO 06005KT
10SM SCT090 SCT110 24/20 A3000 RMK AO2
SLP148 T02390200 53002",
"windDirection":60,
"ICAO":"KCFV",
"seaLevelPressure":1014.8,
"elevation":225,
"countryCode":"US",
"lng":-95.56666666666666,
"temperature":"23.9",
"dewPoint":"20",
"windSpeed":"05",
"humidity":78,
"stationName":"Coffeyville, Coffeyville
Municipal Airport",
"datetime":"2012-07-09 08:52:00",
"lat":37.083333333333336
}
}
Pretty straight forward, except that the API is no longer valid/has limits. In order to finish the project I've instead opted to call this API: http://api.openweathermap.org/data/2.5/weather?lat=37.77&lon=-122.419
Which returns the JSON in this format
{
"coord": {
"lon": 139,
"lat": 35
},
"sys": {
"country": "JP",
"sunrise": 1369769524,
"sunset": 1369821049
},
"weather": [
{
"id": 804,
"main": "clouds",
"description": "overcast clouds",
"icon": "04n"
}
],
"main": {
"temp": 289.5,
"humidity": 89,
"pressure": 1013,
"temp_min": 287.04,
"temp_max": 292.04
},
"wind": {
"speed": 7.31,
"deg": 187.002
},
"rain": {
"3h": 0
},
"clouds": {
"all": 92
},
"dt": 1369824698,
"id": 1851632,
"name": "Shuzenji",
"cod": 200
}
I can make the call just fine, but how do I display the "main" and "description" strings in the "weather" array? More specifically, how do I display this information as a Toast?
Here's what I have:
protected void onPostExecute(String result){
try {
JSONArray weatherArray = new JSONArray(result);
JSONArray wArray = new JSONArray("weather");
String mainWeather = wArray.getString(1);
String mainDescription = wArray.getString(2);
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Log.d("ReadWeatherJSONFeedTask", e.getLocalizedMessage());
}
BecauseI am following the mobiforge Tutorial, I have not deviated anywhere else except for this particular block of code.
Thanks for the help!
Edit:
There are several solutions here that work see #swats and #user3515851. I have chosen #remees-m-syde due to it's simplicity. Primarily because his solution did not require that I go through the for loop.

I have used optJSONArray or optString, instead of getJSONArray or getString as "opt" will return "" if there is no value for that key.. it will not throw any exception like in case of getString()
Try below code
JSONObject rootJsonObj = new JSONObject(result);
JSONArray wArray = rootJsonObj.optJSONArray("weather");
for (int i = 0; i < wArray.length(); i++) {
JSONObject weatherJsonObj = wArray.optJSONObject(i);
String mainWeather = weatherJsonObj.optString("main");
String mainDescription = weatherJsonObj.optString("description");
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();
}
Parsing issue was there, You should have taken object from response result.
EDIT: No need of try catch block while using optJSONArray or optString.

You are unable to get the data because there is one json object inside the "weather" JSONArray.
JSONArray starts with - [
JSONObject starts with - {,
So first get the JSONArray and then the JSONObject inside it.
"weather": [ ----Array
{ ----Object
"id": 804,
"main": "clouds",
"description": "overcast clouds",
"icon": "04n"
}
]
You have to get this JSONObject and then get the String from it like the below code showing.
JSONObject weatherArray = new JSONObject(result);
JSONArray wArray = weatherArray.getJSONArray("weather");
JSONObject jobj = wArray.getJSONObject(0);
String mainWeather = jobj.getString("main");
String mainDescription = jobj.getString("description");
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();
When there is multiple object in Array, Get it as below.
JSONObject rootJsonObj = new JSONObject(result);
JSONArray wArray = rootJsonObj.optJSONArray("weather");
for (int i = 0; i < wArray.length(); i++) {
JSONObject weatherJsonObj = wArray.getJSONObject(i);
String mainWeather = weatherJsonObj.getString("main");
String mainDescription = weatherJsonObj.getString("description");
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();
}

protected void onPostExecute(String result){
try {
JSONObject weatherArray = new JSONObject(result);
JSONArray wArray = weatherArray.getJSONArray("weather");
for(int i=0;i<wArray.length,i++){
JSONObject object=wArray.getJSONObject(i);
String mainWeather=object.getString("main");
String mainDescription=object.getString("description");
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();
}
} catch (Exception e) {
Log.d("ReadWeatherJSONFeedTask", e.getLocalizedMessage());
}
I hope this one will help to you :)

I assume you obtained the weather array from parsing this JSON now to retrieve the values from it
JSONObject object=null;
try {
JSONObject object=array.getJSONObject(0);
String main=object.getString("main");
String description=object.getString("description");
} catch (JSONException e) {
e.printStackTrace();
}
and now use the strings in your toast

Assuming result contains the JSON, here is how to get main, and description form weather :
JSONObject resJSON = new JSONObject(result);
JSONArray weatherArray = resJSON.getJSONArray("weather");
for(int i = 0; i < weatherArray.length(); i++) {
JSONObject weatherJSON = weatherArray.getJSONObject(i);
System.out.println(weatherJSON.getString("main"));
System.out.println(weatherJSON.getString("description"));
}

Recently, I found out json2pojo useful tool for json parsing, works with anything Jackson,Gson,Java etc.
Hope this will help you.

Try this
JSONObject weatherObject = new JSONObject(result);
JSONArray wArray = weatherObject.getJSONArray("weather");
for (int i = 0; i < wArray.length(); i++) {
JSONObject wObject = wArray.getJSONObject(i);
if(wObject.has("description")) {
Log.d("TAG", wObject.getString("description"));
}
if(wObject.has("main")) {
Log.d("TAG", wObject.getString("main"));
}
}

Use this
JSONObject weatherArray = new JSONObject(result);
JSONArray wArray = new JSONArray("weather");
String mainWeather = ((JSONObject)wArray.getJSONObject(0)).getString("main");
String mainDescription = ((JSONObject)wArray.getJSONObject(0)).getString("description");
Toast.makeText(getBaseContext(), mainWeather + " - "
+ mainDescription,Toast.LENGTH_SHORT).show();

How to read a JSON file using JSON.simple library?

I'm trying to parse a json file using json simple library but I'm having some trouble getting the code to parse the json file. I've done some searching but every example's json file is formatted differently from the one I'm using. I'm able to query the full json file, but I can't get a specific piece of information from my json file and add it to a list (the list turns up empty).
The json file in question (this is a snippet of the original file for simplicity's sake):
{
"status": "ok",
"count": "2",
"data":{
"1":{
"country": "U.S.A.",
"name": "Jeremy",
"id": 1
},
"3":{
"country": "U.K.",
"name": "Dell",
"id": 3
}
}
}
The code I've tried using:
List<String> list = new ArrayList<String>();
String json = myJSONFile; // myJSONFile is a place holder for the location of the file.
JSONObject jsonObject = (JSONObject) JSONValue.parse(json);
JSONObject data = (JSONObject) jsonObject.get("data");
for (int x = 0; y > data.size(); y++)
{
JSONObject id = (JSONObject) data.get(y + "");
list.add((String) id.get("name");
}
// Used to show if the list is empty or not.
JOptionPane.showMessageDialog(null, list);

As pointed out in the comments, you JSON isn't a valid one. You can try parsing it here.
The correct JSON appears to be:
{
"status": "ok",
"count": "2",
"data": {
"1": {
"country": "U.S.A.",
"name": "Jeremy",
"id": 1
},
"3": {
"country": "U.K.",
"name": "Jeremy",
"id": 3
}
}
}
A couple of errors in your code:
1) You are trying to parse the JSON file location without reading it. You need to first read the file containing JSON string
List<String> list = new ArrayList<String>();
String json = "..\\json.txt";
JSONParser parser = new JSONParser();
Object parsed = parser.parse(new FileReader(json));
JSONObject jsonObject = (JSONObject) parsed;
2) Your loop doesn't make much sense. Here you want to try and iterate over the keys returned by your JSONObject represented by data
JSONObject data = (JSONObject) jsonObject.get("data");
Iterator<?> keys = data.keySet().iterator();
while (keys.hasNext()) {
if (data.get(keys.next()) instanceof JSONObject) {
JSONObject id = (JSONObject) data.get(keys.next());
list.add((String) id.get("name"));
System.out.println("Yo => " + (String) id.get("name"));
}
}
Here is the full working sample, modify per your need to make it more generic and best practices:
public static void main(String... args) {
try {
List<String> list = new ArrayList<String>();
String json = "..\\json.txt"; //Location of your json file
JSONParser parser = new JSONParser();
Object parsed = parser.parse(new FileReader(json));
JSONObject jsonObject = (JSONObject) parsed;
JSONObject data = (JSONObject) jsonObject.get("data");
Iterator<?> keys = data.keySet().iterator();
while (keys.hasNext()) {
if (data.get(keys.next()) instanceof JSONObject) {
JSONObject id = (JSONObject) data.get(keys.next());
list.add((String) id.get("name"));
System.out.println("Yo => " + (String) id.get("name"));
}
}
// Used to show if the list is empty or not.
JOptionPane.showMessageDialog(null, list);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Output: