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Java JSONObject won't transform arrays into Json?

I'm using this code in Java:
JSONObject jsonObject = new JSONObject(response.body().string());
and it will lead to null when I put strings like
[{...},{...}, ..., {...}]
where {...} is a valid JsonObject.
What should I do? I guess json must begin with { and end with } always. That's because it's null. What should I do? Is there a way to make JSON library deal with this automatically? I can't control the place from where I receive this string of 'json array'.

Because the string you've given isn't an object, but an array.
You'll have to read it like that (using Java EE's JSON libraries):
JsonArray array = jsonReader.readArray();

getJSONObject error: JSONObject["..."] is not a JSONObject

I'm trying to parse a JSON string, but getting an error when trying to get a nested object:
JSONObject jsonObject = new JSONObject(jsonString);
System.out.println(jsonObject);
System.out.println(jsonObject.keySet());
System.out.println(jsonObject.getJSONObject("matches"));
Below is the output in console. As far as I can see, the JSON is valid as jsonObject is created without an error. But when I try to obtain "matches" it throws an error. I've compared my code with tutorials but I can't see what the issue out to be:
{"matches":[{"id":233028,"awayTeam":{...
[matches, count, filters, competition]
Error in client: JSONObject["matches"] is not a JSONObject.
Anything I'm doing wrong? Happy to provide any further info if needed.

matches is an array, not an object. Use getJSONArray:
System.out.println(jsonObject.getJSONArray("matches"));
(Or more usefully:
System.out.println(Arrays.deepToString(jsonObject.getJSONArray("matches")));
since System.out.println on an array doesn't really show useful information on its own.)

Java parsing from escaped json string

There are many threads related to this, but I can't solve my issue.
I get this string from parsing an iterable using GSON.
Iterable<ParametrosProveedores> proveedoresList;
proveedoresList = proveedoresRepository.findAll(); //From spring repository
String jsonString = gson.toJson(proveedoresList);
jsonString value is:
[{\"id\":1,\"proveedor\":\"CALIXTA\",\"unaVia\":true,\"dosVias\":true,\"plazasSi\":\"todas\",\"plazasNo\":\"\",\"turnoUnaVia\":false,\"turnoDosVias\":false},{\"id\":2,\"proveedor\":\"MOVILE\",\"unaVia\":true,\"dosVias\":true,\"plazasSi\":\"51,52\",\"plazasNo\":\"\",\"turnoUnaVia\":false,\"turnoDosVias\":false},{\"id\":3,\"proveedor\":\"TWILIO\",\"unaVia\":true,\"dosVias\":true,\"plazasSi\":\"todas\",\"plazasNo\":\"51\",\"turnoUnaVia\":false,\"turnoDosVias\":false},{\"id\":4,\"proveedor\":\"OTRO\",\"unaVia\":true,\"dosVias\":true,\"plazasSi\":\"todas\",\"plazasNo\":\"\",\"turnoUnaVia\":false,\"turnoDosVias\":false}]
Which is a json array. Is there really no way to parse from that string without removing escapes manually?
All I want to do is:
JSONArray jsonArray = parseFrom(jsonString);
Is it possible?

Since you are using a generic in the form of an Iterable<T>, you may need to use:
String jsonString = gson.toJson(proveedoresList, typeOfSrc);
Where typeOfSrc is the type of your proveedoresList. that way gson knows how to serialize the object properly.

Get list of string from list of Json object

I am trying to extract list of string from following Json
"example":{[
{"#name":"name1"},
{"#name":"name2"},
{"#name":"name3"},
{"#name":"name4"}
]}
I want to get the list of #name values. I am using jayway jsonpath to do this.
I tried the following code,
List<String> response = null;
try{
ReadContext ctx = JsonPath.parse(data);
response = ctx.read(xPath);
}catch(Exception e){
AppLogger.EventLogger.error(e.getMessage());
response = null;
}
return response;
but got an exception saying could not find the specified path. I have used the following jsonPath example.#name
Can someone tell me What went wrong in my code? how to extract list #name values.
Expected output :
[name1,name2,name3,name4]

I have made small changes to your json in order to make it valid.
{"example":[
{"#name":"name1"},
{"#name":"name2"},
{"#name":"name3"},
{"#name":"name4"}
]}
and the code which specified works perfectly fine with the following expression:
$.example[*].#name
There are a lot of online services which can help validate your json.
One of them is jsonlint.com
I would also recommend to look at json.org.

Decode json object to string android

I used json_encode(); to convert string to json in php and then response it to android but I can't use the response, how can I convert the json to string?
when I display the response it shows this :
"{\n'OK': \n[\n{\n'Name': 'MyName',\n'Gender':'Male'\n}\n]\n}"
what shall I do?
thank you

Since you're just converting a string to json, you're not returning a JSONObject or JSONArray, according to: http://php.net/manual/en/function.json-decode.php
If you must return a string, you may have to use some json library or write your own parser.
If that doesn't sound appealing, I recommending returning a JSONObject or JSONArray with one element.
For example:
php
echo json_encode( array('result' => 'the string you are encoding') );
java
JSONObject json = new JSONObject( encodedStringResponseFromPhp );
String theStringYouEncoded = (String) json.get( "result" );
You'll need to add a throws JSONException to the function you add this java code too or put it inside a try catch block.

Have you tried using a JSON-Library like https://code.google.com/p/json-simple/? Looks like you need some help decoding the string.

Edit: You should use the json2.js library from Douglas Crockford. It provides some extra features and better/older browser support.
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