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Android - How to correctly write a JSONObject string

I'm trying to read/write a json file. But after the first write the json is escaped and reading it again doesn't work. I have the following json structure but with a lot more value :
{
"events": {
"XdQKixgtraz17eDHb6OW": {
"department": "Côte-d'Or",
"objectName": "Dijon",
"uid": "PMhzfzWlm6vN2yL1kY2i"
}
}
}
Here is how i build my json string :
JSONObject eventsJsonObject = new JSONObject();
JSONObject eventsData = new JSONObject();
for(Event event: eventsList){
String eventString = gson.toJson(event);
eventsData.put(event.getUid(), eventString);
}
eventsJsonObject.put("events", eventsData);
writeFile(filename, eventsJsonObject.toString());
I end up with a string looking like this and i can't read it again .. :
{"events":{"XdQKixgtraz17eDHb6OW":"{\"department\":\"Côte-d'Or\",\"objectName\":\"Dijon\",\"uid\":\"PMhzfzWlm6vN2yL1kY2i\"}"}}
As you can see there is a quote before the third semi colon that shouldn't be there. How can i correctly build my json string ?
Thanks for your time.
Edit : The error came from where i build my json string to write in file so i have rewrite my question.

Try this code
public static JSONObject readJSONFile (String path, Context context) {
String jsonStr = null;
try {
InputStream is = getActivity().getAssets().open(path);
int size = is.available();
byte[] buffer = new byte[size];
is.read(buffer);
is.close();
jsonStr = new String(buffer, "UTF-8");
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
JSONObject jsonObj = new JSONObject((jsonStr ));
return jsonObj;
}

ObjectOutputStream.writeUTF writes corrupt characters at the start

this is my .json file:
{"Usuarios":[{"password":"admin","apellido":"Admin","correo":"Adminadmin.com","direccion":"Admin","telefono":"Admin","nombre":"Admin","username":"admin"}]}
(I tried to translate my code from Spanish to English in the comments as best I could <3)
The function that writes in the JSON is this one:
public void agregarUsuario(String nombre, String apellido, String direccion, String telefono, String correo, String username, String password) {
try {
//String jsonString = JsonObject.toString();
JSONObject usuarios = getJSONObjectFromFile("/usuarios.json");
JSONArray listaUsuario = usuarios.getJSONArray("Usuarios");
JSONObject newObject = new JSONObject();
newObject.put("nombre", nombre);
newObject.put("apellido", apellido);
newObject.put("direccion", direccion);
newObject.put("telefono", telefono);
newObject.put("correo", correo);
newObject.put("username",username);
newObject.put("password", password);
listaUsuario.put(newObject);
usuarios.put("Usuarios",listaUsuario);
ObjectOutputStream outputStream = null;
outputStream = new ObjectOutputStream(new FileOutputStream("C:\\Users\\Victor\\eclipse-workspace\\Iplane\\assets\\usuarios.json"));
outputStream.writeUTF(usuarios.toString());
outputStream.flush();
outputStream.close();
}catch(JSONException e) {
e.printStackTrace();
}catch(Exception e) {
System.err.println("Error writting json: " + e);
}
So, if in my "create user" JFrame window ,I create a new user with "asdf" as info within all the user's details, I should get the following JSON file:
{"Usuarios":[{"password":"admin","apellido":"Admin","correo":"Adminadmin.com","direccion":"Admin","telefono":"Admin","nombre":"Admin","username":"admin"},{"password":"asdf","apellido":"asdf","correo":"asdf","direccion":"asdf","telefono":"asdf","nombre":"asdf","username":"asdf"}]}
And yes! that happens! but I got also, some weird ascii/Unicode symbols in front if my JSON main object. I cant copy the output here, so this is my output on imgur: link.
Why this problem happens? how could I fix it?
If someone need my json file reader (maybe the problem is there) here you go:
public static InputStream inputStreamFromFile(String path) {
try {
InputStream inputStream = FileHandle.class.getResourceAsStream(path); //charge json in "InputStream"
return inputStream;
}catch(Exception e) {
e.printStackTrace(); //tracer for json exceptions
}
return null;
}
public static String getJsonStringFromFile(String path) {
Scanner scanner;
InputStream in = inputStreamFromFile(path); //obtains the content of the .JSON and saves it in: "in" variable
scanner = new Scanner(in); //new scanner with inputStream "in" info
String json= scanner.useDelimiter("\\Z").next(); //reads .JSON and saves it in string "json"
scanner.close(); //close the scanner
return json; //return json String
}
public static boolean objectExists (JSONObject jsonObject, String key) { //verifies whether an object exist in the json
Object o;
try {
o=jsonObject.get(key);
}catch(Exception e) {
return false;
}
return o!=null;
}
public static JSONObject getJSONObjectFromFile(String path) { //creates a jsonObject from a path
return new JSONObject(getJsonStringFromFile(path));
}
So, after writing in JSON file, I cant do anything with it, because with this weird symbols, I got errors in my json: "extraneus input: (here are the symbols) expecting [STRING, NUMBER, TRUE, FALSE, {..."

writeUTF does not write standard unicode but prepends the output with two bytes of length information
If you use writeUTF intentionally, you have to use readUTF to read the data again. Otherwise I would suggest using an OutputStreamWriter.
writeUTF()
Writes two bytes of length information to the output stream, followed
by the modified UTF-8 representation of every character in the string
s. If s is null, a NullPointerException is thrown. Each character in
the string s is converted to a group of one, two, or three bytes,
depending on the value of the character.
** Edit to clarify OutputStreamWriter:
To use the OutputStreamWriter just replace the ObjectOutputStream with OutputStreamWriter and use write instead of writeUTF.
You might find this small tutorial helpfull: Java IO: OutputStreamWriter on jenkov.com

Parsing Representation in Restlet

I am getting JSONException when I try to put in JSONObject.
#Post
public String someCode(Representation rep) throws ResourceException{
try {
rep.getText();
} catch (IOException e) {
LOGGER.error("Error in receiving data from Social", e);
}
try {
JSONObject json = new JSONObject(rep);
String username = json.getString("username");
String password = json.getString("password");
String firstname = json.getString("firstname");
String lastname = json.getString("lastname");
String phone = json.getString("phone");
String email = json.getString("email");
LOGGER.info("username: "+username); //JsonException
LOGGER.info("password: "+password);
LOGGER.info("firstname: "+firstname);
LOGGER.info("lastname: "+lastname);
LOGGER.info("phone: "+phone);
LOGGER.info("email: "+email);
} catch (JSONException e) {
e.printStackTrace();
}
return "200";
}
ERROR LOG:
org.json.JSONException: JSONObject["username"] not found.
at org.json.JSONObject.get(JSONObject.java:516)
at org.json.JSONObject.getString(JSONObject.java:687)
NOTE:
When I try to print rep.getText(), I get the following data:
username=user1&password=222222&firstname=Kevin&lastname=Tak&phone=444444444&email=tka%40gmail.com

Your rep object isn't a JSON object. I actually think that when you pass it to JSONObject(), it only captures a weird string. I suggest to parse it into an array :
Map<String, String> query_pairs = new LinkedHashMap<String, String>();
String query = rep.getText();
String[] pairs = query.split("&");
for (String pair : pairs) {
int idx = pair.indexOf("=");
query_pairs.put(URLDecoder.decode(pair.substring(0, idx), "UTF-8"), URLDecoder.decode(pair.substring(idx + 1), "UTF-8"));
}

What you are Receiving in the POST is HTTP Form encoded data not JSON.
Restlet can and does handle these objects natively providing the Form object to interact with them. rather than new JSONObject(String) try new Form(String), for example:
String data = rep.getText();
Form form = new Form(data);
String username = form.getFirstValue("username");
I leave the remainder as an exercise to the reader.
Alternatively you will need to adjust the client submitting the data to encode it in JSON see http://www.json.org/ for the description of this syntax.
For reference the Form class is org.restlet.data.Form in the core Restlet library.

Format a String in Json style

I extracted a huge String from a webpage and want to style/formatting this in Json style. The extracted String was originally a Json format but now after extracting this is just a long String. I used JsonObj for this and the formatter does curios things, he moved text from the bottom to top changed the generally the line orders etc.
http://pastebin.com/exwwc6SY JsonFile after Formatting
http://pastebin.com/WHXtE36G The extracted String
And here the code
try {
FileWriter fw = new FileWriter("/tmp/1.txt");
String line = ROUtils.getStringFromInputStream(urlConnection.getInputStream());
System.out.println(line);
String jsonObj = new JSONObject(line).toString(2);
fw.write(jsonObj);
} catch (IOException e) {
e.printStackTrace();
}
And the getStringFromInputStream() method
public static String getStringFromInputStream(InputStream is) {
BufferedReader br = null;
StringBuilder sb = new StringBuilder();
String line;
try {
br = new BufferedReader(new InputStreamReader(is));
while ((line = br.readLine()) != null) {
sb.append(line);
}
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
if (br != null) {
try {
br.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
return sb.toString();
}
Update
I found a new issue. The JsonObj File its not equal to the original String.
I compared the number of Characters (no spaces). The original String has 96311 and the JsonObj has 92636. Can anyone give me a hint what should I do?

You cannot and should not rely on the ordering of elements within a JSON object.
From the JSON specification at http://www.json.org/
An object is an unordered set of name/value pairs.

I found it out why i missed 4000 characters after converting.
I forgot to close the FileWriter!
fw.close();
The close() methods calls the flush() method so that the last buffered piece of the String can written down.
Thank u guys.

Unable to split json response?

This is my method
public String buildJsonData(String username , String message)
{
JsonObject jsonObject = Json.createObjectBuilder().add("Username",username+":"+message).build();
StringWriter stringWriter = new StringWriter();
try(JsonWriter jsonWriter = Json.createWriter(stringWriter))
{
jsonWriter.write(jsonObject);
}
catch(Exception e)
{
System.out.print("buildJsonData ="+e);
}
return stringWriter.toString();
}
If i input username as john and message as hello.I get output as
{"Username":"john:hello"}
But I want output without braces and doublequotes I want my output as
John:hello
I tried to split it using array[0] but didn't get the output.Is it possible in json to get my desired output(without braces and quotes).

On the sending end, you would put the Username and Message entities into a JSONObject and send the resulting string over the network.
On the receiving end, you would unmarshal the JSON to extract the entities. You can then format them however you like.
Please read about JSON encoding here.
This is a simple example:
private String getResponse(){
JSONObject json = new JSONObject();
try {
json.put("Username", "John");
json.put("Message", "Hellow");
} catch (JSONException e) {
e.printStackTrace();
}
return json.toString();
}
private void receiver(){
try {
JSONObject response = new JSONObject(getResponse());
String username = response.getString("Username");
String message = response.getString("Message");
System.out.println(String.format("%s : %s", username,message));
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

Your structure is not really JSON.
A json structure would be like
{
Username : "John",
Message : "Hello"
}
Anf if your want to really use JSON, there is not way to remove braces and quotes. This IS Json.
If you want to output only the part you quoted, store the json value in a variable
String myoutput = stringWriter.toString();
And then remove the parts you don't want with replace() or a regexp

Braces are part of the JSON notation - they indicate an object. If you remove them, then it's not JSON any more. Same goes for double quotes.You are creating your JSON object as:
Json.createObjectBuilder().add("Username",username+":"+message)
This creates an object with property named Username and value john:hello. Again, this is the JSON notation. It's not intended to be read directly, but to facilitate data transfer between applications (on the same or different devices).
If all you want to create is john:message, then instead of creating a JSON object, you should simply do:
String result = username + ":" + message;
return result;