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JSON Parsing on error body (JSON Exception) org . json.JSONException: End of input at character 0

I am getting an error org . json.JSONException: End of input at character 0
This is my Code :-
JSONObject jObjError = new JSONObject(response.errorBody().string());
Log.e("Error","::"+jObjError.getString("error_codes"));
and this is my JSON
{
"errors":{
"provider":["already has an appointment scheduled at this time."]
},
"error_codes":["provider_unavailable"]
}
Can anyone help me with this

The key point here is that you're trying to get a string from an array, not directly from an object. The correct way of parsing this would be:
JSONObject jObjError = new JSONObject(response.errorBody().string());
JSONArray errorArray = jObjError.optJSONArray("error_codes");
for(int i = 0;i<errorArray.size;i++) {
Log.e("Error","::"+errorArray.get(i));
}

If response is your returned JSON, you should pass it directly as parameter is it's of type String
JSONObject jo=new JSONObject(response);
and then do whatever else. because your error messages are customized and returned as json string so this is interpreted as successful request with customized messages.

Android jsonobject to listview socketio

I made a chat app using socket.io and node.js and I got data like as in JSON object.
Here is my code
db.query('select email from users ', function(err, rows , field) {
if (err) throw err;
let getuser={"get":rows};
socket.emit('getuser',getuser);
});
In android I get the data and show the email data using Toast.makeText
JSONObject data = (JSONObject) args[0];
try {
String get =data.getString("get");
Toast.makeText(getApplicationContext(), get, Toast.LENGTH_SHORT).show();
} catch (JSONException e) {}
But I wanna show email list (userlist) by using a simple ListView.
How can I get a string array from a JSON object?
Please help me.

You need to get JSON Array from JSONObject then convert it to List of model class by loop and parse it or by GSON Library then show result list on ListView
JSONObject data = (JSONObject) args[0];
try {
JSONArray userlist = data.getJSONArray("get");
} catch (JSONException e) {}

How should I parse JSON?

I am trying to parse this json.
However, it is not working ...
I want to parse expected_departure_time of all the buses such as 4 , 15, C1, 4A in departure
this is my code which is not working.
try{
String str = response.getString("departures");
JSONArray jsonArray = response.getJSONArray(str);
JSONObject bus = jsonArray.getJSONObject(0);
String four = bus.getString("expected_departure_time");
textView.append(four);
}catch (JSONException e){
e.printStackTrace();
}
JSON
https://transportapi.com/v3/uk/bus/stop/6090282/live.json?app_id=d7180b02&app_key=47b460aac35e55efa666a99f713cff28&group=route&nextbuses=yes

The error you're making is that you're considering "departures" as a JsonArray, which is not the case in your JSON example, it is a JsonObject (Which in my opinion is a poor way of constructing this Json).
Anyway, you will have to get all the JsonObjects inside the "departure" JsonObject by doing this:
try
{
String jsonString=response.toString();
JSONObject jObject= new JSONObject(jsonString).getJSONObject("departures");
Iterator<String> keys = jObject.keys();
while( keys.hasNext() )
{
String key = keys.next();
JSONArray innerJArray = jObject.getJSONArray(key);
//This is your example, you can add a loop here
innerJArray(0).getString("expected_departure_time");
}
}
catch (JSONException e)
{ e.printStackTrace(); }

If you need to use the transport API for other features, to convert JSON strings to Java objects, you can map automatically by using GSON.
Follow the instructions from Leveraging the gson library and map any response you want from this API.

Retrieve specific value inside array from json response in android

I need to get the value of idinside studentarray. The response I get is,
{
"response": {
"student": [
{
"id": "125745",
"module": 3,
"status": 1
}
]
}
}
I tried using following code,
String userId = null;
try {
JSONObject object = (JSONObject) new JSONTokener(response).nextValue();
userId= object.getString("id");
} catch (JSONException e) {
e.printStackTrace();
}
But it doesn't work. How do I retrieve id?

You are almost there, just you need to do this:
JSONArray students = object.getJSONArray("student");
JSONObject student = students.getJSONObject(0);
userId= student.getString("id");
Because the id value is placed in a JSONObject, then inside a JSONArray at index 0, then it is again placed inside a JSONObject.
Also don't forget to handle exceptions, the code above, is just for your understanding.
Hope that helps!!

Your value is placed in json array. So, you need to retrieve response object using getJSONObject and then get student json array via getJSONArray. Then you will be able to iterate through student objects. There is no way to magically get id from json.
Alternatively, you can map your json to Java objects using Gson, for example.

Try this :
Let all of the json is called
String serverResponse = "Response from the server";
try {
JSONObject object = new JSONObject(serverResponse);
String userId = object.getJSONObject("response").getJSONArray("student").getJSONObject(0).getString("id");
}
catch (JSONException e) {
e.printStackTrace();
}
Hope this helps.

Assuming jsonObject is a reference to your root json, you can get id of the first student:
JSONObject response = (JSONObject) jsonObject.get("response");
JSONArray students = (JSONArray) response.get("student");
int id = (int) ((JSONObject)students.get(0)).get("id");

Creating a JSON response from Google Application Engine

Purely as an academic exercise I wanted to convert one of my existing GAE applets to return the response back to Android in JSON and parse it accordingly.
The original XML response containing a series of booleans was returned thus:
StringBuilder response = new StringBuilder();
response.append("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
response.append("<friend-response><added>");
response.append(friendAdded);
response.append("</added><removed>");
response.append(friendRemoved);
response.append("</removed><found>");
response.append(friendFound);
response.append("</found></friend-response>");
I want to replace this with a JSON response that looks something like this:
{ "friendResponse" : [ { "added":true, "removed":false, "found":true } ]}
I think I can generate the array contents as follows (I haven't tested it yet) but I don't know how to create the top-level friendResponse array itself. I can't seem to find any good examples of creating JSON responses in Java using the com.google.appengine.repackaged.org.json library. Can anyone help put me on the right path?
boolean friendAdded, friendRemoved, friendFound;
/* Omitted the code that sets the above for clarity */
HttpServletResponse resp;
resp.setContentType("application/json");
resp.setHeader("Cache-Control", "no-cache");
JSONObject json = new JSONObject();
try {
//How do I create this as part of a friendResponse array?
json.put("added", friendAdded);
json.put("removed", friendRemoved);
json.put("found", friendFound);
json.write(resp.getWriter());
} catch (JSONException e) {
System.err
.println("Failed to create JSON response: " + e.getMessage());
}

You need to use JSONArray to create the (single-element) array that will store your object:
try {
JSONObject friendResponse = new JSONObject();
friendResponse.put("added", friendAdded);
friendResponse.put("removed", friendRemoved);
friendResponse.put("found", friendFound);
JSONArray friendResponseArray = new JSONArray();
friendResponseArray.put(friendResponse);
JSONObject json = new JSONObject();
json.put("friendResponse", friendResponseArray);
json.write(resp.getWriter());
} catch (JSONException e) {
System.err
.println("Failed to create JSON response: " + e.getMessage());
}

You can use GSON: https://sites.google.com/site/gson/gson-user-guide#TOC-Object-Examples
With this framework, you can serialize an object to json, and vice versa.