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Get the count of entries from a json file

I am trying to get json data from a fake api call and need to get the count of the items in it(so that in future I can call the actual restful service). I am not able to get the number of departments in the json. I am expecting the result as 4(int) here.
I am not able to get the string value(json) for the code below:
String json = client.target("file:///C:/Program%20Files%20(x86)/apache-tomcat-8.0.35/webapps/GetProducts.json").request(MediaType.TEXT_PLAIN).get(String.class);
Please find below the entire code:
String json = client.target("file:///C:/Program%20Files%20(x86)/apache-tomcat-8.0.35/webapps/GetProducts.json").request(MediaType.TEXT_PLAIN).get(String.class);
JSONObject jsnobject = new JSONObject(json);
JSONArray jsonArray = jsnobject.getJSONArray("locations");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject explrObject = jsonArray.getJSONObject(i);
}
JSON Sample:
{
"Department":
[
{"SectionId":"1","SectionName":"Childrens Wear"},
{"SectionId":"2","SectionName":"Womens Wear"},
{"SectionId":"3","SectionName":"F&A"},
{"SectionId":"1","SectionName":"Mens Wear"}
]
}
I am new to java as well as api's.
Thanks,

You are either using incorrect key in code or you posted incorrect JSON example. You used locations as the key incode however there is no value against that key in sample JSON. You need to use Department as the key.
JSONArray jsonArray = jsnobject.getJSONArray("Department");

Getting Json object inside a Json object in Java

So I have some code that is able to send this out:
{"id":1,
"method":"addWaypoint",
"jsonrpc":"2.0",
"params":[
{
"lon":2,
"name":"name",
"lat":1,
"ele":3
}
]
}
The server receives this JSON object as a string named "clientstring":
JSONObject obj = new JSONObject(clientstring); //Make string a JSONObject
String method = obj.getString("method"); //Pulls out the corresponding method
Now, I want to be able to get the "params" value of {"lon":2,"name":"name","lat":1,"ele":3} just like how I got the "method".
however both of these have given me exceptions:
String params = obj.getString("params");
and
JSONObject params = obj.getJSONObject("params");
I'm really at a loss how I can store and use {"lon":2,"name":"name","lat":1,"ele":3} without getting an exception, it's legal JSON yet it can't be stored as an JSONObject? I dont understand.
Any help is VERY appreciated, thanks!

params in your case is not a JSONObject, but it is a JSONArray.
So all you need to do is first fetch the JSONArray and then fetch the first element of that array as the JSONObject.
JSONObject obj = new JSONObject(clientstring);
JSONArray params = obj.getJsonArray("params");
JSONObject param1 = params.getJsonObject(0);

How try like that
JSONObject obj = new JSONObject(clientstring);
JSONArray paramsArr = obj.getJSONArray("params");
JSONObject param1 = paramsArr.getJSONObject(0);
//now get required values by key
System.out.println(param1.getInt("lon"));
System.out.println(param1.getString("name"));
System.out.println(param1.getInt("lat"));
System.out.println(param1.getInt("ele"));

Here "params" is not an object but an array. So you have to parse using:
JSONArray jsondata = obj.getJSONArray("params");
for (int j = 0; j < jsondata.length(); j++) {
JSONObject obj1 = jsondata.getJSONObject(j);
String longitude = obj1.getString("lon");
String name = obj1.getString("name");
String latitude = obj1.getString("lat");
String element = obj1.getString("ele");
}

Extracting JSON fields using java

I am trying to extract a person's details who liked a facebook page by passing the page id as parameter. I extracted the JSON content of that page and now from that I want to extract name and id of users.
How do I achieve that ?
Code:
JSONObject json = readurl("https://graph.facebook.com/pageid");
System.out.println(json.toString());
System.out.println("Page id is:"+json.get("id"));
JSON:
"likes":{
"data":[
{
"id":"*******",
"name":"vv"
},
{
"id":"********",
"name":"abc"
},

Code like this would do the trick.
JSONObject json = readurl("https://graph.facebook.com/pageid");
JSONArray dataJsonArray = json.getJSONArray("data");
for(int i=0; i<dataJsonArray.length; i++) {
JSONObject dataObj = dataJsonArray.get(i);
String id = dataObj.getString("id");
//Similarly you can extract for other fields.
}
Basically data is a JSONArray since it starts with [. So simply get would not work, you must use JSONArray.
Note: I haven't compiled this code, but I think I gave you idea to proceed. Also refer this link to get hold of basics of parsing JSON in java.

This snippet is not tested, but I'm pretty sure it works:
JSONArray data = json.getJSONArray("data");
for (int i=0; i < data.length(); i++) {
JSONObject o = data.getJSONObject(i);
sysout(o.getString("id");
sysout(o.getString("name");
}

I use google's Gson library from: https://code.google.com/p/google-gson/

simpleJson parsing in Java

I'm very new to parsing JSON. I have looked all over and cannot seem to grasp the idea to my particular problem. I'm having a hard time understanding how to get a JSON object from a JSON array. My example is below
[{"styleId":94,
"status":"verified",
"abv":"4.2",
"name":"Bud Light"}]
Here is my current code
JSONParser parser = new JSONParser();
Object obj = parser.parse(inputLine);
JSONObject jsonObject = (JSONObject) obj;
Long currPage = (Long)jsonObject.get("currentPage");
System.out.println(currPage);
JSONArray jArray = (JSONArray)jsonObject.get("data");
System.out.println(jArray);
inputLine is my orignal JSON. I have pulled a JSONArray out of the original JSONObject that has the "data" tag. Now this is where I'm stuck and given the JSONArray at the top. Not sure how to iterate through the Array to grab JUST the "name" tag.
Thanks for the help in advanced!

To iterate in a JSONArray you need to go through each element in a loop.
int resultSize = jArray.length();
JSONObject result;
for (int i = 0; i < resultSize; i++) {
result = resultsArray.getJSONObject(i);
String name = result.getString("name");
// do whatever you want to do now...
}

just use Gson . it works well out of the box with any object type you supply.
This is an example from the user's guide:
int[] ints2 = gson.fromJson("[1,2,3,4,5]", int[].class);

how to use json in java for 10 datas

hello
i have an some 10 datas from db with attribute same attribute name
JSONObject json = new JSONObject();
json.put("text",value1);
json.put("title",value2);
json.put("url",value3);
i use this above code i am getting similar to this
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"}
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"}
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"}
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"}
while i parse it in php i am getting an null value i dont know y .. can you tell me where i am wrong...

your output should be something like this to be parsable
[{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"},
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"},
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"},
{"text":"texting is not bad","title":"tesing","url":"http:\/\/www.example.com\/"}]
and for this you should be using JSONArray.

Basically you will have to create a JSON Array to hold your 10 datas, like so:
JSONArray jsonArray = new JSONArray();
for (int i = 0; i < 10; i++) {
JSONObject json = new JSONObject();
json.put("text",value1);
json.put("title",value2);
json.put("url",value3);
jsonArray.put(json);
}
Output, See Bala R's response.