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How to get values from JSONObject in Java?

I am trying to parse a JsonArray and get its values but I am gettign error when I use
jitem.getString("firstitem");
or
jitem.getJSONObject("firstitem");
or
jitem.get("firstitem");
Following is the code snippet.
JSONArray arr_items = new JSONArray(str);
if(arr_items!=null && arr_items.size()>0){
for(int i=0;i<arr_items.size();i++){
JSONObject jitem = arr_items.getJSONObject(i);//works fine till here
jitem.getString("firstitem"); //throws exception here
}
This is the JSONArray that I am parsing
[{"firstitem":"dgfd","secondtitem":"dfgfdgfdg","thirditem":"fdgfdgdf#sjhasjkdsha.com","fourthitem":"jkksdjklsfjskj"}]
what I am doing wrong? How to get these values by using keys?
Update:Note This array and its parameters are not null at all. They all have valid values.

First check arr_items is not empty.
Then, try surrounding your snippet with try/catch :
try {
your snippet
} catch (JSONException e) {
e.printStackTrace();
}

Check below
String json ="{'array':" + "[{'firstitem':'dgfd','secondtitem':'dfgfdgfdg','thirditem':'fdgfdgdf#sjhasjkdsha.com','fourthitem':'jkksdjklsfjskj'}]"+ "}";
JSONObject myjson = new JSONObject(json);
JSONArray the_json_array = myjson.getJSONArray("array");
int size = the_json_array.length();
// ArrayList<JSONObject> arrays = new ArrayList<JSONObject>();
for (int i = 0; i < size; i++) {
JSONObject another_json_object = the_json_array.getJSONObject(i);
// arrays.add(another_json_object);
System.out.println(another_json_object.get("firstitem"));
}
it require some array name so appended array name to it , if you want without it you have to add GSON.

How to Read Json array values from file

JSONArray jsonArray = (JSONArray) obj;
When I use the above code, it shows the error message:
java.lang.ClassCastException: org.json.simple.JSONObject cannot be cast to org.json.simple.JSONArray
Please anyone suggest any method to overcome this error or any other way to read json value form a file in Java (Desktop application).

Use this for get json value in string format from file
public String loadJSONFromFile() {
String json = null;
try {
InputStream is = getActivity().getAssets().open("yourfilename.json");
int size = is.available();
byte[] buffer = new byte[size];
is.read(buffer);
is.close();
json = new String(buffer, "UTF-8");
} catch (IOException ex) {
ex.printStackTrace();
return null;
}
return json;
}
JsonObject is a child of a JsonArray, so as per my suggestion use like this
final JSONArray jsonArray = new JSONArray();
jsonArray.put(obj); //obj is your JsonObject
and you can get JsonObject from array like
jsonArray.getJSONObject(0); //0 is index of your JsonObject in JsonArray
Hope this help you.

Check the content of the file.
It seems that the content is not an array, but a json object.
Open the file with a text editor. If the content is something like:
{ // First character
... content here
} // Last character
it is an object, if it is similar to
[ // First character
... content here
] // Last character
it is an array.
If you need to read an object you need to change your code as follow:
JSONObject jsonObject = (JSONObject) obj;

JSONArray jsonArray = (JSONArray) obj;
This obj is of JsonObject type, so change that line to
JSONObject jsonObject = (JSONObject)obj;

getString not working for JSON key

I'm learning how to work with JSON's in java and I'm having a problem using getString for one of my keys. My code is here:
public static void getJSON(String matchID){
String s = "";
String test = "{\"employees\":[{\"firstName\":\"John\", \"lastName\":\"Doe\"}]}";
try {
JSONObject hi = new JSONObject(test);
JSONArray stuff = hi.getJSONArray("employees");
String[] items = new String[stuff.length()];
items[0] = stuff.getString("firstName");
} catch (JSONException e) {
e.printStackTrace();
}
}
The "getString" is underlined in red, and the "The method getString(int) in the type JSONArray is not applicable for the arguments (String)" I was following an answer to another question word for word almost, and this happens, any advice? Thanks!
EDIT:
I need to get the specifics by name ie. "firstName" because I will be working with thousands of JSONs that each have hundreds of lines.

You need to get the JSOnObject first from the JSONArray(stuff) before you can call getString().
if you want to get the first element in the jsonarray and get its string this is how you would do it
JsonObject obj = stuff.getJsonObject(0);
String name = obj.getString("firstname");

So I figured out my problem, I didn't realize I had an JSONObject first, my apologies. Fixed like this:
JSONObject hi = new JSONObject(test);
JSONArray stuff = hi.getJSONArray("employees");
JSONObject name = stuff.getJSONObject(0);
String[] items = new String[hi.length()];
items[0]=name.getString("firstName");
System.out.println(items[0]);

you can try the simplest way to Parse in JSON
JSONParser parser=new JSONParser();
String s = "{\"employees\":[{\"firstName\":\"John\", \"lastName\":\"Doe\"}]}";
try{
Object obj = parser.parse(s);
JSONArray array = (JSONArray)obj;
System.out.println(array.get(1));
}catch(ParseException pe){
}

android java.lang.string cannot be converted to jsonarray

I've been searching through the Internet for a while, still have no idea what should I do... here's my code:
String res = "...";
JSONArray jArr = new JSONArray(res);
res contains following:
[["000000000001","club1","www.example.com","some adress"],["000000000002","club2","www.example.com","some adress2"]]
I just keep getting this error and don't know how to fix it, please help :C

I tried your code and its working fine. Here is the code I tried :
String res = "[[\"000000000001\",\"club1\",\"www.example.com\",\"some adress\"],[\"000000000002\",\"club2\",\"www.example.com\",\"some adress2\"]]";
try {
jArr = new JSONArray(res);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Log.e("Array", "" + jArr.toString());
and here is the output :
[["000000000001","club1","www.example.com","some adress"],["000000000002","club2","www.example.com","some adress2"]]

Android application to web server with JSON lib

i have a problem which i cant solve for days.
the String line input is "{"name":"John", "Hobby":"Cycle"}" sent from a JSON from PHP server
The code at android application
public void testFn()
{
try {
while ((line = reader.readLine()) != null) {
String tmp = gson.toJson(line.toString());
JSONObject jobj = (JSONObject)new JSONParser().parse(tmp);
sb.append(jobj.get(1).toString() + "\n");
}
}catch ....
}
i wanted to convert the string received and convert it to a JSONObject / JSONArray which i can retrieve it or display to TextView as a String format. but i keep getting the error of CastException from java.String to JSON.simple.JSONObject..
Hope someone could enlighten me on this

class MyJsonObject{
private String name;
private String Hobby;
MyJsonObject() {
}
}
MyJsonObject obj = new MyJsonObject();
Gson gson = new Gson();
String json = gson.toJson(obj);
(Deserialization)
MyJsonObject obj2 = gson.fromJson(json, MyJsonObject.class);

Try
String str = "{\"name\":\"John\", \"Hobby\":\"Cycle\"}";
//i wrote preceded "\" to very " because it is code format string,
//not came from internet. You can pass direct response from PHP server
try {
JSONObject json = new JSONObject(str);
Log.d("Home",json.getString("name"));
Log.d("Home",json.getString("Hobby"));
} catch (JSONException e1) {
e1.printStackTrace();
}

Basically now i edited my code here
String line = "{"name":"John","Hobby":"Cycle"}";
Object obj=parser.parse(line);
JSONArray array=(JSONArray)obj;
JSONObject obj2 = (JSONObject)array.get(0);
System.out.println(obj2.get("name").toString());
sorry i figured out a way.
Output:
John