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Can we convert a string to JSON Array using the json-simple-1.1.1.jar library?

I want to convert a string into a JSON Array using the json-simple-1.1.1.jar library and came up with the following code,
import org.json.simple.*;
public class RESTclient {
public static void main(String[] args) {
String output = "[{\"Symbol\":\"AMZN\",\"Name\":\"Amazon.com Inc\",\"Exchange\":\"NASDAQ\"},{\"Symbol\":\"VXAZN\",\"Name\":\"CBOE Amazon VIX Index\",\"Exchange\":\"Market Data Express\"}]";
JSONObject jsonObject = new JSONObject(output);
String[] names = JSONObject.getNames(jsonObject);
JSONArray jsonArray = jsonObject.toJSONArray(new JSONArray(names));
System.out.println(jsonArray);
}
}
I want the output to be a JSON Array. What am I doing wrong here?

What am I doing wrong here?
You're trying to convert a String that contains a JSON array into a JSONObject
JSONObject jsonObject = new JSONObject(output);
Your content represents a JSON array so parse it as such
JSONParser parser = new JSONParser();
JSONArray jsonArray = (JSONArray) parser.parse(output);
Note that other libraries, like Gson and Jackson, have much better abstractions for JSON arrays and objects (JsonArray, ArrayNode). Consider using those instead.

SimpleJson: String to JSONArray

I get the following JSON:
[
{
"user_id": "someValue"
}
]
It's saved inside a String.
I would like to convert it to a JSONObject which fails (as the constructor assumes a JSON to start with {). As this doesn't seem to be possible I'd like to convert it to a JSONArray. How can I do that with SimpleJson?

JSONParser parser = new JSONParser();
JSONArray array = (JSONArray)parser.parse("[{\"user_id\": 1}]");
System.out.println(((JSONObject)array.get(0)).get("user_id"));
You need to cast to a JSONArray as that is what the string contains.

For your task you could use code as bellow:
String t = "[{\"user_id\": \"someValue\"}]";
JSONParser parser = new JSONParser();
JSONArray obj = (JSONArray) parser.parse(t);
System.out.println(obj.get(0));
And result would be JSONObject.

String actualJsonObject = // assuming that this variable contains actual object what ever u want to pass as per your question says
JSONParser parser = new JSONParser();
JSONArray userdataArray= (JSONArray) parser.parse(actualJsonObject );
if(userdataArray.size()>0){
for (Object user : userdataArray) {
JSONObject jsonrow=(JSONObject)parser.parse(String.valueOf(user));
String User_Id= (String)jsonrow.get("user_Id"); \\ Each User_Id will be displayed.
} else{
System.out.println("Empty Array....");
}

It works for me.
String jsonString = "[{\"user_id\": \"someValue\"}]";
JSONArray jsonArray = new JSONArray();
JSONParser parser = new JSONParser();
try {
jsonArray = (JSONArray) parser.parse(js);
} catch (ParseException e) {
e.printStackTrace();
}

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){
}

Convert String to JSON Array from Web Request

i wanted to know how I can convert this string here to an array:
[{"title":"test","birth":"20.05"},{"title":"test","birth":"13.05"},{"title":"test","birth":"13.06"},{"title":"test","birth":"23.06"},{"title":"test","birth":"01.12"},{"title":"test","birth":"01.06"}]
I already found this here:
JSONObject jsnobject = new JSONObject(readlocationFeed);
JSONArray jsonArray = jsnobject.getJSONArray("locations");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject explrObject = jsonArray.getJSONObject(i);
But if I try to make the object I always get null. And here:
JSONArray jsonArray = jsnobject.getJSONArray("locations");
I don't know what I should enter as "locations". Should I enter "[]" ?
Thanks really much for help!
Daniel

I don't know what I should enter as "locations". Should I enter "[]" ?
Nothing readlocationFeed is already a JSONArray. You just need
JSONArray jsonArray = new JSONArray(readlocationFeed);
without
JSONObject jsnobject = new JSONObject(readlocationFeed);
JSONArray jsonArray = jsnobject.getJSONArray("locations");

Shouldn't it be the other way around?
JSONArray jsnArray = new JSONArray(readlocationFeed);
Anyway I suggest you should use GSON for this kind of problem:
Gson gson = new Gson();
MyClass[] arr = gson.fromJson(str, MyClass[].class);
class MyClass{
double birth;
String title;
}

org.json.simple.JSONArray cannot be cast to org.json.simple.JSONObject

I'm trying to parse below json file:
{"units":[{"id":42,
"title":"Hello World",
"position":1,
"v_id":9,
"sites":[[{"id":316,
"article":42,
"clip":133904
}],
{"length":5}]
}, ..]}
This is what I have tried:
Object obj = null;
JSONParser parser = new JSONParser();
Object unitsObj = parser.parse(new FileReader("file.json");
JSONObject unitsJson = (JSONObject) unitsObj;
JSONArray units = (JSONArray) unitsJson.get("units");
Iterator<String> unitsIterator = units.iterator();
while(unitsIterator.hasNext()){
Object uJson = unitsIterator.next();
JSONObject uj = (JSONObject) uJson;
obj = parser.parse(uj.get("sites").toString());
JSONArray jsonSites = (JSONArray) obj;
for(int i=0;i<jsonSites.size();i++){
JSONObject site = (JSONObject)jsonSites.get(i); // Exception happens here.
System.out.println(site.get("article");
}
}
The code is not working when I try to parse the inner json array, so I get:
Exception in thread "main" java.lang.ClassCastException: org.json.simple.JSONArray cannot be cast to org.json.simple.JSONObject
The exception is pointing to this line:
JSONObject site = (JSONObject)jsonSites.get(i);
Any help? tnx.

I've found a working code:
JSONParser parser = new JSONParser();
Object obj = parser.parse(content);
JSONArray array = new JSONArray();
array.add(obj);
If you don't need the array (like the author), you can simply use
JSONParser parser = new JSONParser();
Object obj = parser.parse(content);

The first element of the sites array is an array, as you can see indenting the JSON:
{"units":[{"id":42,
...
"sites":
[
[
{
"id":316,
"article":42,
"clip":133904
}
],
{"length":5}
]
...
}
Therefore you need to treat its value accordingly; probably you could do something like:
JSONObject site = (JSONObject)(((JSONArray)jsonSites.get(i)).get(0));

this worked:
System.out.println("resultList.toString() " + resultList);
org.json.JSONObject obj = new JSONObject(resultList);
org.json.JSONArray jsonArray = obj.getJSONArray(someField);
for(int i=0;i<jsonArray.length();i++){
System.out.println("array is " + jsonArray.get(i));
}

JSONObject site=jsonSites.getJSONObject(i) should work out

JSONObject obj=(JSONObject)JSONValue.parse(content);
JSONArray arr=(JSONArray)obj.get("units");
System.out.println(arr.get(1)); //this will print {"id":42,...sities ..}
#cyberz is right but explain it reverse

You can first read the whole content of file into a String.
FileInputStream fileInputStream = null;
String data="";
StringBuffer stringBuffer = new StringBuffer("");
try{
fileInputStream=new FileInputStream(filename);
int i;
while((i=fileInputStream.read())!=-1)
{
stringBuffer.append((char)i);
}
data = stringBuffer.toString();
}
catch(Exception e){
LoggerUtil.printStackTrace(e);
}
finally{
if(fileInputStream!=null){
fileInputStream.close();
}
}
Now You will have the whole content into String ( data variable ).
JSONParser parser = new JSONParser();
org.json.simple.JSONArray jsonArray= (org.json.simple.JSONArray) parser.parse(data);
After that you can use jsonArray as you want.

If you want to re-filter the json data you can use following method. Given example is getting all document data from couchdb.
{
Gson gson = new Gson();
String resultJson = restTemplate.getForObject(url+"_all_docs?include_docs=true", String.class);
JSONObject object = (JSONObject) new JSONParser().parse(resultJson);
JSONArray rowdata = (JSONArray) object.get("rows");
List<Object>list=new ArrayList<Object>();
for(int i=0;i<rowdata.size();i++) {
JSONObject index = (JSONObject) rowdata.get(i);
JSONObject data = (JSONObject) index.get("doc");
list.add(data);
}
// convert your list to json
String devicelist = gson.toJson(list);
return devicelist;
}

JSONObject site = (JSONObject)jsonSites.get(i); // Exception happens here.
The return type of jsonSites.get(i) is JSONArray not JSONObject.
Because sites have two '[', two means there are two arrays here.

use your jsonsimpleobject direclty like below
JSONObject unitsObj = parser.parse(new FileReader("file.json");

JSONObject baseReq
LinkedHashMap insert = (LinkedHashMap) baseReq.get("insert");
LinkedHashMap delete = (LinkedHashMap) baseReq.get("delete");