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Loop all data from json in java

I have a problem with Java when I try to display all of content from cmd's elements. So here is my code:
public static void main(String[] args) throws Exception {
// Json Stream Reader
String jsonS = "";
// Connect to web api
URL url = new URL("http://b50172e8.ngrok.io/api/plugin/521100d075c1284b944841394e157744");
// Make Connection
URLConnection conn = url.openConnection();
conn.setRequestProperty("Accept","*/*");
conn.connect();
// Stream reader
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String inputLine;
while((inputLine = in.readLine()) != null) {
jsonS+=inputLine;
}
// Read json response
Gson gson = new Gson();
// Json Object
JsonObject jsonObject= gson.fromJson(jsonS, JsonObject.class);
JsonElement data = jsonObject.get("data");
System.out.println(data);
// Close connection
in.close();
}
Output:
[{"cmd":"cmd-1"},{"cmd":"cmd-2"},{"cmd":"cmd-3"}]
I want to use foreach of cmd to display the following:
cmd-1
cmd-2
cmd-3

Try this code. I hope it helps.
public static void main(String[] args) throws Exception {
// Json Stream Reader
String jsonS = "";
// Connect to web api
URL url = new URL("http://b50172e8.ngrok.io/api/plugin/521100d075c1284b944841394e157744");
// Make Connection
URLConnection conn = url.openConnection();
conn.setRequestProperty("Accept","*/*");
conn.connect();
// Stream reader
BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String inputLine;
while((inputLine = in.readLine()) != null) {
jsonS+=inputLine;
}
// Read json response
Gson gson = new Gson();
// Json Object
JsonObject jsonObject= gson.fromJson(jsonS, JsonObject.class);
JsonArray data = jsonObject.getAsJsonArray("data");
//here data is JsonArray and it contains everithing: [{"cmd":"cmd-1"},{"cmd":"cmd-1"},{"cmd":"cmd-1"}]
data.forEach(el -> {
//Get Json object which has key and value -> {"cmd":"cmd-1"}
JsonObject jo = el.getAsJsonObject();
//get the value as Json element -> "cmd-1"
JsonElement je = jo.get("cmd");
//Then make the json element string
String value = je.getAsString();
System.out.println(value);
});
//System.out.println(data);
// Close connection
in.close();
}

Receive data from a webservice using REST API

I need to get specific data from this API http://countryapi.gear.host/v1/Country/getCountries?pName=Australia, convert it to String and write out on the console. I want to get data only for Australia. How can I get data in String format only for Name and Alpha2Code like this:
Australia, AU? I was trying to use EntityUtils.toString(response) but it doesn't work.
This is my code:
public class Client {
public static void main(String[] args) throws ClientProtocolException, IOException {
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet("http://countryapi.gear.host/v1/Country/getCountries?pName=Australia");
request.addHeader("accept", "application/json");
HttpResponse response = client.execute(request);
HttpEntity entity = response.getEntity();
InputStream stream = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
String line = reader.readLine();
System.out.println(line);
}
}
The code actually return JSON for Australia, like this:
enter image description here

Try something like this:
Gson gson = new Gson();
JsonObject result = gson.fromJson(line, JsonObject.class);
JsonArray response = result.getAsJsonArray("Response");
Country country = gson.fromJson(response, Country.class);

You can use java api for json parsing. I am just writing a sample code. YOu can explore json parsing api more on below URL:
http://www.oracle.com/technetwork/articles/java/json-1973242.html
JsonObject obj = rdr.readObject();
JsonArray results = obj.getJsonArray("data");
for (JsonObject result : results.getValuesAs(JsonObject.class)) {
System.out.print(result.getJsonObject("name").getString("name"));
System.out.print(": ");
System.out.println(result.getString("message", ""));
System.out.println("-----------");
}

Parsing JSON Object from a JSON array

I am currently developing an app and need to parse JSON objects from inside an unnamed array.
I can only manage to parse JSON arrays with a name such as this one: http://jsonparsing.parseapp.com/jsonData/moviesDemoItem.txt.
The code that I used for the one above is
protected String doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
String asd = buffer.toString();
JSONObject parentObject = new JSONObject(asd);
JSONArray parentArray = parentObject.getJSONArray("movies");
JSONObject fObject = parentArray.getJSONObject(0);
String movie = fObject.getString("movie");
int year = fObject.getInt("year");
return movie + year;
The code includes "movies" which is the array name .
What should I change to parse only the objects from within a JSON array such as https://restcountries.eu/rest/v1/all?

Your countries list is simply an array. Doesn't need a name.
Simply replace
JSONObject parentObject = new JSONObject(asd);
with
JSONArray parentObject = new JSONArray(asd);
See this post for how to iterate over that array to parse the remainder of the objects.
How to parse JSON in Android
Starting something like
for (int i=0; i < parentObject.length(); i++) {
Alternatively, Volley's JsonArrayRequest would be useful, or learning about Retrofit+Gson would be even better if you don't feel like manually parsing the JSON data yourself.

How to get values from mixed type json?

I have string in JSON format. For example:
{
"blockedStatus":true,
"cars":[
"RAW:123",
"TVU:123"
],
"phones":[
"370665566",
"3706324231"
]
}
This is output from server. I need to get seperate values but I don't know how to do it.
Tried this:
BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
StringBuilder builder = new StringBuilder();
for (String line = null; (line = reader.readLine()) != null;) {
builder.append(line).append("\n");
}
JSONTokener tokener = new JSONTokener(builder.toString());
JSONArray finalResult = new JSONArray(tokener);
Log.e("IO-OUTPUT", builder.toString()); //prints json output
Log.e("finalResult (1)", finalResult.getString(1));
But I get ant exception:
W/System.err(31249): org.json.JSONException: Value {"blockedStatus":true,"cars":["RAW"],"phones":["65431"]} of type org.json.JSONObject cannot be converted to JSONArray
Is there another way to get values? Because calculating symbols and getting values from it will be too hard

change
JSONTokener tokener = new JSONTokener(builder.toString());
JSONArray finalResult = new JSONArray(tokener);
to
JSONObject jsonObject = new JSONObject(builder.toString());
JSONArray carsResult = jsonObject.getJSONArray("cars");
JSONArray phoneResult = jsonObject.getJSONArray("phones");
your string rapresent a JSONObject which contains two JSONArray's, cars and phones, and a pair key/value blockedStatus .
Also, if you read the logcat, it says:
type org.json.JSONObject cannot be converted to JSONArray
You can not convert a JSONObject to a JSONArray, which means the you have a JSONObject

Try this
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet();
request.setURI(new URI(url));
HttpResponse response = client.execute(request);
InputStream ips = response.getEntity().getContent();
responseString = response.toString();
responseString = intputStreamToStringConvertor(ips);
JSONObject object = new JSONObject(responseString);
Boolean status = object.getBoolean("blockedStatus");
JsonArray cars = object.getJSONArray("cars");
JsonArray phones = object.getJSONArray("phones");

How to read resulting JSON data into Java ?

I am trying to read results of a JSON request into java, yet
The partial output of my JSON request looks like this :
"route_summary": {
"total_distance": 740,
"total_time": 86,
"start_point": "Marienstraße",
"end_point": "Feldbergstraße"
}
I would like to use the standard json library to extract the values in total_distance.
However I only seem to be able to get the 'route_summary' by doing this :
JSONObject json = null;
json = readJsonFromUrl(request);
json.get("route_summary");
Where
public static JSONObject readJsonFromUrl(String url) throws IOException, JSONException {
InputStream is = new URL(url).openStream();
try {
BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8")));
String jsonText = readAll(rd);
JSONObject json = new JSONObject(jsonText);
return json;
} finally {
is.close();
}
}
What I want is get 'into' route_summary, any clue / tip would be great !

You need to get route_summary, as you already did, and from that object you need to get the total_distance. This will give you back the route_summary.total_distance.
Code sample:
JSONObject object = new JSONObject(s);
int totalDistance = object.getJSONObject("route_summary").getInt("total_distance");

I would recommend you to use GSON library. You can create class which will represent the message and then automatically map JSON to object by invoking function: gson.fromJson(message, YourMessageClass.class).getRoute_summary().
Here is the example of such approach: https://sites.google.com/site/gson/gson-user-guide/#TOC-Object-Examples