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When I convert my java class into jsonobject it reshuffles the order of class members

I am using objectmapper to convert the class into json.
Following is the code:
JSONParser parser = new JSONParser();
ObjectMapper mapper = new ObjectMapper();
String obj = mapper.writeValueAsString(myClass);
JSONObject jsonObject = (JSONObject)parser.perse(obj);
now line number 4 where I get the jsobObject reshuffles the order of class member.
See the attached image, before it converting to jsonobject "authorisation" was first element then signatries.
But at line 4 it becomes 2nd ..... why ?
I want order to be preserved, that is the requirement of my project.
Please help !

You can configure the ordering this way :
#JsonPropertyOrder({ "authorisation", "signatoryDetails", "requestedLimits" })
public class MyClass { ... }

Java read Json array in Json object

I have a String like this:
{"api_authentication":{"api_response":{"token":"XXXXXXXXXXXXXXXXXXXXXXXXX","firstname":"John","disabled":false,"attempts":0,"id":123,"lastname":"Malkovitch","expire":false,"status":0}}}
I can turn this string into an object:
JSONObject jobj = new JSONObject(response);
But I don't find how to get the token value, I tried creating JSONArrays but i get a not found exception.

You can do it like this ;
final JSONObject api_authentication = jobj.getJSONObject("api_authentication");
final JSONObject api_response = api_authentication.getJSONObject("api_response");
System.out.println(api_response.getString("token"));
if JSON any value in curlybrackets { ... } , this is jsonObject . If values are in [ ... ], this is JsonArray. Also you can get which one is object or array, and get it relevant fields from this. So all of json elements are with curly bracket in your problem. Get it as JsonObject.

this might work by the look of what you have posted. The posted code snippet shows that it is a single JSON object and not a JSONArray.
Hence try the following:
JSONObject jobj = new JSONObject(response);
String newtoken = jobj.getJSONObject("api_authentication").getJSONObject("api_response").getString("token"); //declare the variable `newtoken` somhwere before of a desired type

You could try something like:
Object tokenValue = jobj.getJSONObject("api_authentication").getJSONObject("api_response").get("token");
After that you can cast the object to the desired type or use something like getString(.) straightaway.

JSON traversing in java

i want traverse and get particular value from the json i am giving below .
json={"resultMessage":["{\"retain24ErrorMessage\":\"No result data found!\"}","TemplateId or instanceId is empty!"],"isSuccessful":true}
The value i want to get is retain24ErrorMessage value. I have tried the following.
Object JSONArrayCheck = json.get("resultMessage");
String errMsg1 = (String)json.getJSONArray("resultMessage").get(0);
Gson gson = new Gson();
// JsonElement jsonObject = gson.toJsonTree(json.getJSONArray("resultMessage").get(0));
JsonElement jelement = new JsonParser().parse(gson.toJson(errMsg1));
JsonObject jobject = jelement.getAsJsonObject();
But is not working and following error comes
12-11 17:17:16.300: W/System.err(1780): java.lang.IllegalStateException: Not a JSON Object: "{\"retain24ErrorMessage\":\"No result data found!\"}"
. Can you give me demo for retrieving the same retain24ErrorMessage ?

gson.toJson(errMsg1) expects an Object but the passed errMsg1 is a string.
Don't you need to do something like this instead?
JsonElement jelement = new JsonParser().parse(errMsg1);

Insert node in a JSON String

Using Google Gson library how can I inject a element in the root node of a JSON string?
With JSON.Simple it very easy:
String json = ...
JSONObject jsonObj = (JSONObject) JSONValue.parse(json);
jsonObj.put("hey", "yow!");
json = jsonObj.toJSONString(); // Now we have injected a node element
I've been figuring out how can do this with Gson. You might ask why I need Gson when I can do this with JSON.Simple library; the answer is that, there's a handy object serialization/deserialization function that the library have.

The code is strikingly similar:
String json = ...;
JsonObject jsonObj = (JsonObject) new JsonParser().parse(json);
jsonObj.addProperty("hey", "yow!");
json = jsonObj.toString();

How to deserialize a jsonarray into a List<Map> in java using flexjson.deserializer?

In the client side, I have constructed a JSOnARRAY like this:
{"filterEntries":[{"dataName":"mainContact","filterValue":"BILLGATES"}]}.
On the server side (java), I can retireve the values using :
jfilter = JSONValue.parse(jsonFilterStr); //jsonFilterStr={"filterEntries":[{"dataName":"mainContact","filterValue":"BILLGATES"}]}.
JSONArray jFilterEntries = (JSONArray) jfilter.get("filterEntries");
for (int i=0;i<jFilterEntries.size();i++){
JSONObject jFilterEntry = (JSONObject) jFilterEntries.get(i);
String dataName = (String) jFilterEntry.get("dataName");
String filterValue = (String) jFilterEntry.get("filterValue");
}
But the existing app is using flex.json.deserializer and I am unable to achieve the same using flex.json.deserializer. How should I proceed?
I wish to do something like this:
JSONDeserializer jsonDeserializer = new JSONDeserializer();
jsonDeserializer.use(null, List.class);
List<Map<String,String>> lMap= (List<Map<String,String>>)jsonDeserializer.deserialize(params);

Remember the top object that wraps the array. You have to handle that as well. You have to tell it to expect a Map inside the List. To do that you have to specify the type contained in the list by using the path expression "values".
Map<String,List<Map<String,String>>> result = new JSONDeserializer<Map<String,List<Map<String,String>>>>()
.use("values",List.class)
.use("values.values", Map.class)
.deserialize( json);
List<Map<String,String>> filterEntries = result.get("filterEntries");
Updated: Add the new keyword, and made the generic types on the right match the left.