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how I can get data from JSONObject with Java?

I have an String called inputJson that contains
{"listPruebas": [
{
"nombrePrueba" : "pruebaA",
"id" : 1,
"tipoPrueba" : "PRUEBABASE1",
"elementoBase" : "tipoA",
"listaMarca": [
{
"elemento": "elemento1 ",
"tipo": "ABC",
"cadena": "SFSG34235WF32"
},
{
"elemento":"elemento2",
"tipo":"DEF",
"cadena":"DJRT64353GSDG"
},
{
"elemento" : "elemento3",
"formato ":"JPG"
}
]},
{
"nombrePrueba" : "pruebaB",
"id" : 2,
"tipoPrueba" : "PRUEBABASE2",
"elementoBase" : "imagenPrueba",
"listaMarca2": [
{
"elemento" : "imagen",
"tipo": "tipo5",
"cadena": "iVBORw0KGgoAAAANSUhEUgAAAgAAAA"
}
]
}
],
"listaBuscar":
[
{
"tipoBusqueda":"busqueda1",
"id" : 1,
"operacion" : "operacion1",
"valor" : "12"
},
{
"tipoBusqueda":"binario",
"id" : 2,
"operacion" : "operacion2",
"valor" : "13"
},
{
"tipoFiltro":"numerico",
"id" : 31,
"operacion" : "MENOR_QUE",
"valor" : "1980",
"intervalo" : 1
}
]
}
and I converted the String to JSONObject of this way
JSONObject object = new JSONObject(inputJson);
and I got this
jsonObject::{"listaBuscar":[{"valor":"12","id":1,"operacion":"operacion1","tipoBusqueda":"busqueda1"},{"valor":"13","id":2,"operacion":"operacion2","tipoBusqueda":"binario"},{"tipoFiltro":"numerico","intervalo":1,"valor":"1980","id":31,"operacion":"MENOR_QUE"}],"listPruebas":[{"listaMarca":[{"tipo":"ABC","elemento":"elemento1","cadena":"SFSG34235WF32"},{"tipo":"DEF","elemento":"elemento2","cadena":"DJRT64353GSDG"},{"elemento":"elemento3","formato":"JPG"}],"elementoBase":"tipoA","tipoPrueba":"PRUEBABASE1","nombrePrueba":"pruebaA","id":1},{"elementoBase":"imagenPrueba","tipoPrueba":"PRUEBABASE2","listaMarca2":[{"tipo":"tipo5","elemento":"imagen","cadena":"iVBORw0KGgoAAAANSUhEUgAAAgAAAA"}],"nombrePrueba":"pruebaB","id":2}]}
and now I need to extract information but I dont know how to do, for example I try this
object.getString("elemento1");
but I got this error
Caused by: org.json.JONException: JSONObject["elemento1"] not found
help me please

You can't get a nest JSON object from the top level. It's like a treemap. You need to convert it into a java object or get it level by level.
check this post, a lot of ways.

You json contains two json arrays, fetch them as -
JSONArray listaBuscArray = jsonObj.getJSONArray("listaBuscar");
JSONArray listPruebasArray = jsonObj.getJSONArray("listPruebas");
Now you can process and use them as -
for(int i=0; i<listaBuscArray.length; i++){
JSONObject obj = listaBuscArray.getJSONObject(i);
.... your logic
}

Java Parsing A Json File Line To Return Part Of The Line

I am having some trouble trying to figure out how to parse a line in a json file so that it only returns part of the line as a string. I will illustrate below:
public String GetDistance(String origin, String destination) throws MalformedURLException, IOException {
//URL url = new URL("https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&origins" + origin + ",UK+destination=" + destination + ",UK&key=mykey");
URL url = new URL("https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&origins=Cornwall,UK&destinations=London,UK&key=mykey");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
String line, outputString = "";
BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
while ((line = reader.readLine()) != null) {
if (line.contains("distance")) {
outputString = reader.readLine().trim();
return outputString;
}
}
return outputString;
}
What this function does is create a json file in my browser using Google Maps API:
{
"destination_addresses" : [ "London, UK" ],
"origin_addresses" : [ "Cornwall, UK" ],
"rows" : [
{
"elements" : [
{
"distance" : {
"text" : "284 mi",
"value" : 456443
},
"duration" : {
"text" : "4 hours 52 mins",
"value" : 17530
},
"status" : "OK"
}
]
}
],
"status" : "OK"
}
Currently the "outputString" returns the line: "text" : "284 mi". However, the desired output is to just return the miles, "284".
I know this is most likely a re post, however I have been searching around for a solution to this and have been unsuccessful in implementing something that works.
Any help on this would be greatly appreciated, Cheers.

You can have 2 solutions:
Parse the JSON and treat it as an object and then just return the String you're looking for.
Split the line as follows:
outputString = reader.readLine().trim();
That line above returns "text" : "284 mi"
Then you need to split the line by ::
outputString.split(":")
That should create an array with 2 Strings: "text" and "284 mi"
Then take the second String and split it by a space and take the first String:
outputString.split("\\s")
Now you have: "284
Then just return it from subindex 1 till the end, see docs:
outputString.substring(1)
And then just put it all together:
return outputString.split(":")[1].split("\\s")[0].substring(1)
I haven't tried above code but it should work.
BTW follow Java Naming Conventions
firstWordLowerCaseVariable
firstWordLowerCaseMethod()
FirstWordUpperCaseClass
ALL_WORDS_UPPER_CASE_CONSTANT
And use them consistently

Java JSONObject get children

i want to create gmaps on my website.
I found, how to get coordinates.
{
"results" : [
{
// body
"formatted_address" : "Puławska, Piaseczno, Polska",
"geometry" : {
"bounds" : {
"northeast" : {
"lat" : 52.0979041,
"lng" : 21.0293984
},
"southwest" : {
"lat" : 52.0749265,
"lng" : 21.0145743
}
},
"location" : {
"lat" : 52.0860667,
"lng" : 21.0205308
},
"location_type" : "GEOMETRIC_CENTER",
"viewport" : {
"northeast" : {
"lat" : 52.0979041,
"lng" : 21.0293984
},
"southwest" : {
"lat" : 52.0749265,
"lng" : 21.0145743
}
}
},
"partial_match" : true,
"types" : [ "route" ]
}
],
"status" : "OK"
}
I want to get:
"location" : {
"lat" : 52.0860667,
"lng" : 21.0205308
},
From this Json.
I decided to user json-simple
<dependency>
<groupId>com.googlecode.json-simple</groupId>
<artifactId>json-simple</artifactId>
<version>1.1</version>
</dependency>
My code is:
String coordinates = //JSON from google
JSONObject json = (JSONObject)new JSONParser().parse(coordinates);
And i can get the first children: "results"
String json2 = json.get("results").toString();
json2 display correct body of "results"
But i cannot get "location" children.
How to do it ?
Thanks

I think you need to cast the call to json.get("results") to a JSONArray.
I.e.
String coordinates = //JSON from google
JSONObject json = (JSONObject)new JSONParser().parse(coordinates);
JSONArray results = (JSONArray) json.get("results");
JSONObject resultObject = (JSONObject) results.get(0);
JSONObject location = (JSONObject) resultObject.get("location");
String lat = location.get("lat").toString();
String lng = location.get("lng").toString()
The trick is to look at what type the part of the json you're deserializing is and cast it to the appropriate type.

about this link
com.google.gson.JsonParser#parse(java.lang.String) is now deprecated
so use com.google.gson.JsonParser#parseString, it works pretty well
Kotlin Example:
val mJsonObject = JsonParser.parseString(myStringJsonbject).asJsonObject
Java Example:
JsonObject mJsonObject = JsonParser.parseString(myStringJsonbject).getAsJsonObject();

Using Json to access a specific attribute

Hello guys i'm reading a page that contain JSON objects with JAVA (Android)
Here is what the page contains :
{
"destination_addresses" : [ "Safi, Maroc" ],
"origin_addresses" : [ "Avenue Hassan II, Safi, Maroc" ],
"rows" : [
{
"elements" : [
{
"distance" : {
"text" : "1,0 km",
"value" : 966
},
"duration" : {
"text" : "2 minutes",
"value" : 129
},
"status" : "OK"
}
]
}
],
"status" : "OK"
}
I know how to read from the page doing this
JSONObject jArray = new JSONObject(result);
String elements = jArray.getString("rows");
the elements string contain that :
[{"elements" : [{"distance" : {"text" : "1,0 km","value" : 966},"duration" : {"text" : "2 minutes","value" : 129},"status" : "OK"}]}]
But im trying to get the distance value which is "966"
Thx guys

So you are trying to access an entry from the array. See Tutorials or examples. This is basic stuff:
http://www.mkyong.com/java/json-simple-example-read-and-write-json/
You need to actually use a JSONArray (which subclasses JSONObject)

You might want to take a look at this link:
How to parse JSON in Android
But for your particular problem you want to call something like:
int value = jArray.getJSONObject("rows").getJSONObject("elements").getJSONArray("distance").getInteger("value");

Try this..
JSONObject jObj = new JSONObject(result);
JSONArray rows = jObj.getJSONArray("rows");
for(int i = 0; i < rows.length; i++){
JSONObject obj = rows.getJSONObject(i);
JSONArray elements = jObj.getJSONArray("elements");
for(int j = 0; j < elements.length; j++){
JSONObject Jobj = elements.getJSONObject(j);
JSONObject distance = Jobj.getJSONObject("distance");
int distance_value = distance.getInteger("value");
JSONObject duration = Jobj.getJSONObject("duration");
int duration_value = duration.getInteger("value");
}
}

Trying to parse JSON to String in Java

I'm trying to parse this stock info at:
http://www.google.com/finance/info?client=ig&q=csco
that's in JSON format to a map, essentially following this tutorial I saw using the quick-json jar but it keeps giving me an exception and I can't figure out why. Here's the code, any help is greatly appreciated
Tutorial link: https://code.google.com/p/quick-json/
public static void main(String args[]) throws IOException
{
String value="";
URL uri = new URL("http://www.google.com/finance/info?client=ig&q=csco");
BufferedReader input = new BufferedReader(new InputStreamReader(uri.openStream(), "UTF-8"));
while(input.readLine()!=null)
{
value+=input.readLine();
}
JsonParserFactory factory = JsonParserFactory.getInstance();
JSONParser parse = factory.newJsonParser();
Map jsonData =parse.parseJson(value);
System.out.println((String)jsonData.get("e"));
}
Here's the exception I get:
Exception in thread "main" com.json.exceptions.JSONParsingException: #Key-Heirarchy::root[0]/ #Key:: COMMA or ] is expected. but found :...#Position::5
at com.json.utils.JSONUtility.handleFailure(JSONUtility.java:124)
at com.json.parsers.JSONParser.stringLiteralTemplate(JSONParser.java:574)
at com.json.parsers.JSONParser.nonValidatingValueTemplate(JSONParser.java:698)
at com.json.parsers.JSONParser.jsonArrayTemplate(JSONParser.java:454)
at com.json.parsers.JSONParser.parseJson(JSONParser.java:170)
at parser.Scratch.main(Scratch.java:27)
EDIT: I also tried Map jsonData =parse.parseJson(value.substring(3) to start at [ but it still gives me an error

In addition to removing the leading // fix your loop as well. Change
while(input.readLine()!=null) // skipping odd lines
{
value+=input.readLine(); // reading even lines
}
to
String line = null;
while((line = input.readLine()) !=null)
{
value +=line;
}
or, better use a StringBuilder like
String line = null;
StringBuilder json = new StringBuilder();
while((line = input.readLine()) !=null)
{
json.append(line);
}
value = json.substring(3); // removes the leading "// "
EDIT:
I'm not familiar with your JSON parser. With the org.json. Java parser you could do it this way.
JSONArray jsonRoot = new JSONArray(value);
JSONObject quote = jsonRoot.get(0);
System.out.println ("e = " + quote.getString("e"));
But, as a workaround you could strip the [] from StringBuilder as
// removes the leading "// [" and trailing "]"
value = json.substring(4, json.length() - 1);

This json is not a valid, have two "//".
Use http://jsonlint.com/ to validate this

The response from that URL starts with //, which isn't valid JSON:
// [ { "id": "99624" ,"t" : "CSCO" ,"e" : "NASDAQ" ,"l" : "24.00" ,"l_cur" : "24.00" ,"s": "2" ,"ltt":"4:00PM EDT" ,"lt" : "Jun 25, 4:00PM EDT" ,"c" : "-0.05" ,"cp" : "-0.21" ,"ccol" : "chr" ,"el": "24.00" ,"el_cur": "24.00" ,"elt" : "Jun 25, 5:54PM EDT" ,"ec" : "0.00" ,"ecp" : "0.00" ,"eccol" : "chb" ,"div" : "0.17" ,"yld" : "2.83" } ]
According to this and this, the Google Finance API is deprecated anyway, so you may want to find something else.

Following blog has enough number of very good examples on quick-json parser
It has got other competitive parsers examples as well
http://codesnippets4all.com/html/parsers/json/quick-json.htm

Add this to your code:
String line = null;
while((line = input.readLine()) !=null)
{
value += line;
}
value = value.replace("// ", "");
You need to replace the // at the beginning to "clean" the JSON before you can parse it.

It seems you are using old quick-json parser version. Use the latest version for parsing
quick-json-1.0.2.3.jar
I could see that the json is coming as follows,
// [
{
"id": "99624"
,"t" : "CSCO"
,"e" : "NASDAQ"
,"l" : "25.41"
,"l_cur" : "25.41"
,"s": "2"
,"ltt":"3:59PM EDT"
,"lt" : "Jul 10, 3:59PM EDT"
,"c" : "+0.25"
,"cp" : "1.01"
,"ccol" : "chg"
,"el": "25.55"
,"el_cur": "25.55"
,"elt" : "Jul 10, 7:07PM EDT"
,"ec" : "+0.14"
,"ecp" : "0.55"
,"eccol" : "chg"
,"div" : "0.17"
,"yld" : "2.68"
}
]
This is not valid JSON, it should not be preceded by //
// [
remove // and just use from [ till end of the json string
i was able to parse successfully the below json string without //
[
{
"id": "99624"
,"t" : "CSCO"
,"e" : "NASDAQ"
,"l" : "25.41"
,"l_cur" : "25.41"
,"s": "2"
,"ltt":"3:59PM EDT"
,"lt" : "Jul 10, 3:59PM EDT"
,"c" : "+0.25"
,"cp" : "1.01"
,"ccol" : "chg"
,"el": "25.55"
,"el_cur": "25.55"
,"elt" : "Jul 10, 7:07PM EDT"
,"ec" : "+0.14"
,"ecp" : "0.55"
,"eccol" : "chg"
,"div" : "0.17"
,"yld" : "2.68"
}
]
Below is the output i've got with version quick-json-1.0.2.3.jar
{root=[{e=NASDAQ, c=+0.25, div=0.17, l=25.41, lt=Jul 10, 3:59PM EDT, ec=+0.14, ltt=3:59PM EDT, elt=Jul 10, 7:07PM EDT, id=99624, yld=2.68, el_cur=25.55, t=CSCO, cp=1.01, s=2, el=25.55, l_cur=25.41, eccol=chg, ccol=chg, ecp=0.55}]}