Instead of using JSONObject you may use JSONArray. If you really need to convert it to a List you may do something like:

List<JSONObject> list = new ArrayList<JSONObject>();
try {
    int i;
    JSONArray array = new JSONArray(string);
    for (i = 0; i < array.length(); i++)
        list.add(array.getJSONObject(i);
} catch (JSONException e) {
    System.out.println(e.getMessage());
}

You should convert your list to a JSON Array, and just use its toString() function:

JSONArray myArray = new JSONArray(jsonObjlist);

// ...
String arrayToJson = myArray.toString(2);

The int parameter specifies the indent factor to use for formatting.

Instead of getting a List<String> from the JSON Object, you can access the array of fields in the same way you are accessing the array of errors:

public static String getField(JSONObject json, String errorsIndex, String fieldIndex) {
    JSONObject errorJson = json.getJSONArray("errors").getJSONObject(errorIndex);
    String value = errorJson.getJSONArray("fields").getString(fieldIndex);
    return value;
}

Note that get(fieldIndex) has changed to getString(fieldIndex). That way you don't have to cast an Object to a String.

You are asking Jackson to parse a StudentList. Tell it to parse a List (of students) instead. Since List is generic you will typically use a TypeReference

List<Student> participantJsonList = mapper.readValue(jsonString, new TypeReference<List<Student>>(){});

You can use json2csharp.com to Convert your json to object model

• Go to json2csharp.com
• Past your JSON in the Box.
• Clik on Generate.
• You will get C# Code for your object model
• Deserialize by var model = JsonConvert.DeserializeObject<RootObject>(json); using NewtonJson

Here, It will generate something like this:

public class MatrixModel
{
    public class Option
    {
        public string text { get; set; }
        public string selectedMarks { get; set; }
    }

    public class Model
    {
        public List<Option> options { get; set; }
        public int maxOptions { get; set; }
        public int minOptions { get; set; }
        public bool isAnswerRequired { get; set; }
        public string selectedOption { get; set; }
        public string answerText { get; set; }
        public bool isRangeType { get; set; }
        public string from { get; set; }
        public string to { get; set; }
        public string mins { get; set; }
        public string secs { get; set; }
    }

    public class Question
    {
        public int QuestionId { get; set; }
        public string QuestionText { get; set; }
        public int TypeId { get; set; }
        public string TypeName { get; set; }
        public Model Model { get; set; }
    }

    public class RootObject
    {
        public Question Question { get; set; }
        public string CheckType { get; set; }
        public string S1 { get; set; }
        public string S2 { get; set; }
        public string S3 { get; set; }
        public string S4 { get; set; }
        public string S5 { get; set; }
        public string S6 { get; set; }
        public string S7 { get; set; }
        public string S8 { get; set; }
        public string S9 { get; set; }
        public string S10 { get; set; }
        public string ScoreIfNoMatch { get; set; }
    }
}

Then you can deserialize as:

var model = JsonConvert.DeserializeObject<List<MatrixModel.RootObject>>(json);

Using gson it is much simpler. Use following code snippet:

 // create a new Gson instance
 Gson gson = new Gson();
 // convert your list to json
 String jsonCartList = gson.toJson(cartList);
 // print your generated json
 System.out.println("jsonCartList: " + jsonCartList);

Converting back from JSON string to your Java object

 // Converts JSON string into a List of Product object
 Type type = new TypeToken<List<Product>>(){}.getType();
 List<Product> prodList = gson.fromJson(jsonCartList, type);

 // print your List<Product>
 System.out.println("prodList: " + prodList);

How about this ?? Sorry to my bad format... first writting..

Public void convert(Object jsonData){
    Wrapper convertedData = (Wrapper)JSON.deserialize(JSON.serialize(jsonData),Wrapper.Class);

 String objectName   = convertedData.getObjectName();
  (do something....)
}

Class Wrapper{
    String objectName;
    String fieldName;
    ( some else...)

    String getObjectName(){
        return objectName;
    }
}

The original "list" is not well-formed JSON. Perhaps you meant the following:

[{"a":1, "b":2}, {"c":3, "d":4}, {"e":5, "f":6}]

If it is in a file called testFile.json, you can import it as JSON:

jsonLst = Import[FileNameJoin[{"path", "to", "testFile.json"}], "JSON"];

If the snippet is a string called str, you can import it as follows:

jsonLst = ImportString[str, "JSON"];

In either case, you will have a list of lists of rules:

(* jsonLst = {{"a" -> 1, "b" -> 2}, {"c" -> 3, "d" -> 4}, {"e" -> 5, "f" -> 6}} *)

You can now convert this into the structure you desire. One of the several ways to do it is the following:

res = jsonLst // Nest[Map, Apply[List], 2];
(* {{{"a", 1}, {"b", 2}}, {{"c", 3}, {"d", 4}}, {{"e", 5}, {"f", 6}}} *)

EDIT

Following the suggestion by Mr. Wizard, this is indeed more general:

res = jsonLst // ReplaceAll[Rule -> List]

My intention was to actually give a more restricted solution so as to avoid unintended side-effects.

EDIT 2

And following the suggestion by b3m2a1, here is his recommended solution:

res = jsonLst // Replace[#, Rule -> List, {3}, Heads -> True] &

you can get this data as a JsonArray

There is a built-in method to convert a JSONObject to a String. Why don't you use that:

JSONObject json = new JSONObject();

json.toString();