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How parse json object and json array together

i have two situation of Json output .
one is data that found and i have a json array and a json object like this:
{"data":"yes"}[{"id":"10","number":"7","text":"text7","desc":"text7_again","user_code":"0"},{"id":"11","number":"8","text":"text8","desc":"text8_again","user_code":"1"}]
other situation is that data not found :
{"data":"no"}
just one json object.
how parse this data in android client for support two situtaion?

First, you should validate your json in http://jsonlint.com/ if you test it you will look that is a wrong json. So, for make it right, in your server your response should look something like this:
{"data":"yes","response":[{"id":"10","number":"7","text":"text7","desc":"text7_again","user_code":"0"},{"id":"11","number":"8","text":"text8","desc":"text8_again","user_code":"1"}]}
And in that case, in android
JSONObject jsonObj = new JSONObject(response);
if (jsonObj.getString("data").compareTo("yes") == 0) {
JSONArray jsonArray = jsonObj.getJSONArray("response");
//To-Do another code
}
and that's all

Here is a possible case: (you need to fix your json format)
Success -
string resultJSON =
{"success":true,
"data":[
{"id":"10","number":"7","text":"text7","desc":"text7_again","user_code":"0"},
{"id":"11","number":"8","text":"text8","desc":"text8_again","user_code":"1"}]}
Failed -
string resultJSON =
{"success":false}
Then
JSONObject jsonRoot = new JSONObject(resultJSON);
bool isSuccess = jsonRoot.getBoolean("success");
if (isSuccess) {
// do the array parser
for(int i=0; i<jsonData.lenght;i++) {
JSONObject jsonObj = jsonData.getJSONObject(i);
String id = jsonObj.getString("id"); // get the value of id
String desc = jsonObj.getString("desc"); // and so on...
}
}

How to get the multiple text from string in Android?

I am developing the Android for Xively. I get the following text data and store into string.
{"id":111111177,"title":"G-sensor","private":"true","feed":"https://api.xively.com/v2/feeds/111111177.json","auto_feed_url":"https://api.xively.com/v2/feeds/111111177.json","status":"frozen","updated":"2014-08-05T07:14:29.783670Z","created":"2014-08-01T08:29:17.156043Z","creator":"https://xively.com/users/x22819","version":"1.0.0","datastreams":[{"id":"GPIO1","current_value":"1","at":"2014-08-05T07:14:18.991421Z","max_value":"1.0","min_value":"0.0","tags":["xyz"],"unit":{"type":"G","label":"watts"}},{"id":"GPIO2","current_value":"0","at":"2014-08-05T07:14:29.783670Z","max_value":"1.0","min_value":"0.0","tags":["xyz"],"unit":{"type":"G","label":"watts"}},{"id":"GPIO3","current_value":"1","at":"2014-08-05T06:51:08.165217Z","max_value":"1.0","min_value":"1.0"},{"id":"GPIO4","current_value":"0","at":"2014-08-05T06:51:13.029452Z","max_value":"0.0","min_value":"0.0"},{"id":"GPIO5","current_value":"1","at":"2014-08-05T06:51:20.679123Z","max_value":"1.0","min_value":"1.0"},{"id":"GPIO6","current_value":"0","at":"2014-08-05T06:51:27.057369Z","max_value":"0.0","min_value":"0.0"}],"location":{"domain":"physical"},"product_id":"w8tuBsYf835kYTjDFz9w","device_serial":"DWJAXD6N7VDZ"}
There has id and the current_value in the above data , and I want to get the data of id and the current_value from the above text like following text.
GPIO1 1
GPIO2 0
GPIO3 1
GPIO4 0
GPIO5 1
GPIO6 0
How do I capture the the data of id and the current_value from the above text ?
Can somebody teach me how to do ?
Thank in advance.

Try this:
String resultJSON = "datastreams":[{"id":"GPIO1","current_value":"1","at":"2014-08-05T07:14:18.991421Z","max_value":"1.0","min_value":"0.0","tags":["xyz"],"unit":{"type":"G","label":"watts"}},
{"id":"GPIO2","current_value":"0","at":"2014-08-05T07:14:29.783670Z","max_value":"1.0","min_value":"0.0","tags":["xyz"],"unit":{"type":"G","label":"watts"}},
{"id":"GPIO3","current_value":"1","at":"2014-08-05T06:51:08.165217Z","max_value":"1.0","min_value":"1.0"},
{"id":"GPIO4","current_value":"0","at":"2014-08-05T06:51:13.029452Z","max_value":"0.0","min_value":"0.0"},
{"id":"GPIO5","current_value":"1","at":"2014-08-05T06:51:20.679123Z","max_value":"1.0","min_value":"1.0"},
{"id":"GPIO6","current_value":"0","at":"2014-08-05T06:51:27.057369Z","max_value":"0.0","min_value":"0.0"}],"location":{"domain":"physical"},"product_id":"w8tuBsYf835kYTjDFz9w","device_serial":"DWJAXD6N7VDZ"};
JSONObject jsonRoot = new JSONObject(resultJSON);
JSONArray jsonData = jsonRoot.getJSONArray("Data");
for(int i=0; i<jsonData.lenght;i++) {
JSONObject jsonOBject = jsonData.getJSONObject(i);
Log.d(TAG, "json ("+i+") = "+jsonOBject.toString());
// do what you want with your JSONObject , i.e :add it to an ArrayList of paresed result
String ID = jsonOBject.getString("id");
}
Hope this may help you

dataList = new ArrayList<HashMap<String, String>>();
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
myarray = jsonObj.getJSONArray("datastreams");
// looping through All myarray
for (int i = 0; i < myarray.length(); i++) {
JSONObject c = myarray.getJSONObject(i);
String id = c.getString("id");
String date = c.getString("at");
// tmp hashmap for single data
HashMap<String, String> data = new HashMap<String, String>();
// adding each child node to HashMap key => value
data.put(TAG_ID, id);
data.put(TAG_DATE, date);
// adding data to data list
dataList.add(data);
}

The data you have is actually a JSON so you can simply parse it to java POJO. I would suggest to use one of 2 most popular open source parsers GSON or Jackson.
What you have to do is:
Create java POJOs for chosen parser. To make it easier use this online tool http://www.jsonschema2pojo.org/
Copy generated java classes to your project.
Use JSON parser e.g. GSON
Let's say you named your main class as Example, with GSON you can parse it like this:
Gson gson = new Gson();
String data = ....//your JSON data
Example example = gson.fromJson(data, Example.class);
Data you would like to get will have own Java representation and will be available through getter method, e.g.:
List<Datastream> datastreams = example.getDatastreamList();
for (DataStream data : datastreams) {
String id = data.getId();
String currentValue = data.getCurrentValue();
}
Then you can do whatever you like. Please know that GSON can also read streams, so if you already parse stream to string you can skip it and pass that stream to Gson object directly.
If you don't want redundant POJOs or their parameters, you can remove them. GSON will handle it and simply ignore these values. Just make sure that data you are interested in keep the generated structure.
That's how I would do it.

Which is the best way to parse JSON data in Android?

I have JSON data to parse. The structure is not fixed, and sometimes it comes as a single string and other times as an array.
Currently, we are using the GSON library for parsing JSON, but are facing problems when it comes as an array.
For example:
1. {"msg":"data","c":300,"stat":"k"}
2. {
"msg": [
" {\"id\":2,\"to\":\"83662\",\"from\":\"199878\",\"msg\":\"llll\",\"c\":200,\"ts\":1394536776}"
],
"c": 200,
"stat": "k",
"_ts": 1394536776
}
In the example above, sometimes I get msg as a string and sometimes as an array.
Can anyone help me? If I decide to use JSON parsing, it will be very tedious because I have around 20+ API to parse and each API contains a mininum of 50 fields.

You can use JSONObject and JSONArray classes instead of GSON to work with JSON data
for the first example
String jsonStr = "{\"msg\":\"data\",\"c\":300,\"stat\":\"k\"}";
JSONObject jsonObj = new JSONObject(jsonStr);
String msg = jsonObj.getString("msg");
Integer c = jsonObj.getInteger("c");
String stat = jsonObj.getString("stat");
For the second example
String jsonStr = ... // "your JSON data";
JSONObject jsonObj = new JSONObject(jsonStr);
JSONArray jsonArr = jsonObj.getJSONArray("msg");
JSONObject arrItem = jsonArr.getJSONObject(0);
//and so on
Also JSONObject class have method opString, opArray which does not throw exception if data you trying to get is not exist or have a wrong type
For example
JSONArray arr = jsonObj.optJSONArray("msg");
JSONObject msg = null;
if (arr != null) {
msg = arr.getJSONObject(0)
} else {
msg = jsonObj.getJSONObject("msg");
}

You can use Google GSON lib for directly parse the json to class object. This is easy and accurate.Okay do one thing both time code is different, if the code is 300 directly parse the json object without GSON. if the code is 200 the use the GSON (Define the similar java class)
String c= json.getString("c");
if(c.equals("300")
String message = status.getString("msg");

There are two ways to parce JSON.
Manually using Android OS JSON Parser Android JSON Parsing And Conversion
Using GSON Library [Library] (https://code.google.com/p/google-gson/downloads/list). This easy to handle if you know all the parameters and models of json response.

Refer the code snippet below to deserialize your json using Google's Gson library without exceptions.
String jsonStr = "your json string ";
Gson gson = new Gson();
JsonObject jsonObj = gson.fromJson (jsonStr, JsonElement.class).getAsJsonObject();
JsonElement elem = jsonObj.get("msg");
if(elem.isJsonArray()) { //**Array**
ArrayList<MyMessage> msgList = gson.fromJson(elem.toString(), new TypeToken<List<MyMessage>>(){}.getType());
} else if(elem.isJsonObject()) { //**Object**
Note note = gson.fromJson(elem.toString(), MyMessage.class);
} else { //**String**
String note = elem.toString();
}
MyMessage class
public class MyMessage {
String to;
String from;
String msg;
int id;
int c;
long ts;
// Setters and Getters
}

Parse a JSON object value (an Array), not the object

I'm developing an Android application that connects with Facebook using Springframework Android rest client.
With this URL:
https://graph.facebook.com/me/friends?access_token=AUTH_TOKEN
Facebook API returns:
{
"data": [
{
"name": "Friend1",
"id": "123456"
}
]
}
I want to parse the data[] values, as an array:
[
{
"name": "Friend1",
"id": "123456"
}
]
And get a FacebookFriend[].
How can I do it with GSON?

First, you'd need a FacebookFriend class (using public fields and no getters for simplicity):
public class FacebookFriend {
public String name;
public String id;
}
If you created a wrapper class such as:
public class JsonResponse {
public List<FacebookFriend> data;
}
Life becomes far simpler as you can simply do:
JsonResponse resp = new Gson().fromJson(myJsonString, JsonResponse.class);
And be done with it.
If you don't want to create an enclosing class with a data field, you'd use Gson to parse the JSON, then extract the array:
JsonParser p = new JsonParser();
JsonElement e = p.parse(myJsonString);
JsonObject obj = e.getAsJsonObject();
JsonArray ja = obj.get("data").getAsJsonArray();
(You can obviously chain all those methods, but I left them explicit for this demonstration)
Now you can use Gson to map directly to your class.
FacebookFriend[] friendArray = new Gson().fromJson(ja, FacebookFriend[].class);
That said, honestly it's better to use a Collection instead:
Type type = new TypeToken<Collection<FacebookFriend>>(){}.getType();
Collection<FacebookFriend> friendCollection = new Gson().fromJson(ja, type);

It seems, your array contain object.
you can parse it in following way.
JsonArray array = jsonObj.get("data").getAsJsonArray();
String[] friendList = new String[array.size()];
// or if you want JsonArray then
JsonArray friendArray = new JsonArray();
for(int i=0 ; i<array.size(); i++){
JsonObject obj = array.get(i).getAsJsonObject();
String name = obj.get("name").getAsString();
friendList[i] = name;
// or if you want JSONArray use it.
friendArray.add(new JsonPrimitive(name));
}

JSON Array of strings (no objects), extracting data

I have a long JSON string representing a string[] array being returned from a WCF service. The array elements are simply strings, they are not objects. This is an example of the return data
["1|ArrayElement1","2|ArrayElement2","3|ArrayElement3"..."n|ArrayElementn"]
I don't mind the index being included in the string, but I need to parse the strings into an ArrayList in Android so that I can adapt it to a ListView.
Since these technically aren't JSONObjects, how can I iterate over them and extract the string from each array element?

this is a valid JSON array of strings, you can parse it normally like this
JSONArray jsonStrings = json.getJSONArray("items");
String strings[] = new String[jsonStrings.length()];
for(int i=0;i<strings.length;i++) {
strings[i] = jsonStrings.getString(i);
}

Maybe this post can help you out:
JSON Array iteration in Android/Java
HashMap<String, String> applicationSettings = new HashMap<String,String>();
for(int i = 0; i < settings.length(); i++){
String value = settings.getJSONObject(i).getString("value");
String name = settings.getJSONObject(i).getString("name");
applicationSettings.put(name, value);
}
JSONArray names= json.names();
JSONArray values = json.toJSONArray(names);
for(int i = 0 ; i < values.length(); i++){
if(names.getString(i).equals("description")){
setDescription(values.getString(i));
}
else if(names.getString(i).equals("expiryDate")){
String dateString = values.getString(i);
setExpiryDate(stringToDateHelper(dateString));
}
else if(names.getString(i).equals("id")){
setId(values.getLong(i));
}
else if(names.getString(i).equals("offerCode")){
setOfferCode(values.getString(i));
}
else if(names.getString(i).equals("startDate")){
String dateString = values.getString(i);
setStartDate(stringToDateHelper(dateString));
}
else if(names.getString(i).equals("title")){
setTitle(values.getString(i));
}
}

Just to clarify, as I understand it you are receiving a JSON array of strings which are strings of valid JSON prefixed with the array index and a pipe character?
First, I would suggest contacting the creator of this abomination and lecturing them on violating standards. If they won't listen, talk to their bosses. This kind of thing is unacceptable in my opinion and needs to stop.
Second, I'd suggest doing something like this:
string[] element_strings = JSON.deserialize(WCF_string_result);
object[] elements = new object[element_strings.length];
for(int x = 0; x < elements.length; x++)
{
int pipeIndex = element_strings.indexOf("|");
elements[x] = JSON.deserialize(element_strings[x].substr(pipeIndex + 1));
}
Of course this assumes you have some kind of method for deserializing strings of JSON objects. If you don't I'd recommend using the built in library available in Android:
http://developer.android.com/reference/org/json/package-summary.html

If you want to extract specific value from it using Java8 stream on JSONArray. Then this code will help.
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import org.json.JSONArray;
public class JsonArrayTest {
public static void main(String[] args) {
System.out.println("Output - "+ getValue("[{\"id\":\"11\",\"username\":\"ABC\"},{\"id\":\"12\",\"username\":\"ABC\"}]\""));
System.out.println("Output - "+ getValue("[{\"id\":\"13\",\"username\":\"XYZ\"}]\""));
}
private static String getValue(String input) {
JSONArray jsonArray = new JSONArray(input);
return IntStream
.range(0, jsonArray.length()).mapToObj(obj -> jsonArray.getJSONObject(obj))
.filter(filterObj -> filterObj.getString("id") != null && "12".equals(filterObj.getString("id")))
.map(finalObj -> finalObj.getString("username")).collect(Collectors.joining(""));
}
}
Note: This is just an example how can you extract a specific value from JSONArry using stream APIs. You can change the filter condition or drop it according to your requirement.