Develop Reference

JSON Parsing of single array and name of Array

I need to show response on Sign Up, below is my JSON Response.
I should show password is too short(minimum is 5 characters) into one string
{ errors: { password: [ "is too short (minimum is 5 characters)" ] } }
And also I need to parse the response from the following JSON data
as Signature has already been taken
{ errors: { signature: [ "has already been taken" ] } }
Please tell me how to parse the particular data from the JSON data.
Thanks in advance!!!!

You can use below method to parse your data.
private String parseJsonData(String jsonResponse) {
try {
JSONObject jsonObject = new JSONObject(jsonResponse);
JSONObject errorJsonObject = jsonObject.getJSONObject("errors");
JSONArray jsonArray = null;
//has method
if (errorJsonObject.has("password")) {
jsonArray = errorJsonObject.optJSONArray("password");
} else if (errorJsonObject.has(" signature")) {
jsonArray = errorJsonObject.optJSONArray("signature");
}
String errorMessage = jsonArray.getString(0);
return errorMessage;
} catch (JSONException e) {
e.printStackTrace();
return null;
}
}
You can replace unwanted symbols like below code:
errorMessage.repalce("[","");
errorMessage.repalce("]","");
errorMessage.repalce("/"","");

You can use Google's Gson library to do that using the following steps:
Add dependency in your build.gradle(Module:app) file.
dependencies {
implementation 'com.google.code.gson:gson:2.8.5'
}
For latest version of gson library, click here
To parse JSON string to an object use the code below:
Gson gson = new Gson();
// I'm fetching my session stored JSON string
// You can fetch as per your requirement
String jsonStr = session.getJsonStr();
MyObject myObject = (MyObject) gson.fromJson(jsonStr, MyObject.class);
And if you need to convert an object to a JSON string, you can use the below code:
// I'm fetching my session stored Object here
// You can fetch as per your requirement
MyObject myObject = session.getMyObject();
String jsonStr = gson.toJson(myObject);
Make sure you design your object appropriate for the JSON string to match the data types. If you are not sure of the data types in the JSON, you can use this site or any parse and view website to view them.
Hope it helps!

Just try this,
try {
String tost = null;
JSONObject object = new JSONObject(json);
JSONObject errorObject = object.getJSONObject("errors");
if (errorObject.has("password")){
tost = "password "+errorObject.getJSONArray("password").get(0).toString();
} else if (errorObject.has("signature")){
tost = "signature "+errorObject.getJSONArray("signature").get(0).toString();
}
Toast.makeText(MainActivity.this, tost, Toast.LENGTH_SHORT).show();
}catch (Exception e){
e.printStackTrace();
}

How to extract info from String in android studio? [duplicate]

This question already has answers here:
How do I parse JSON in Android? [duplicate]
(3 answers)
Closed 5 years ago.
I am trying to display information retrieved from server using php in an android app,I have retrieved the information in a String with json formatting here is the retrieve code and php code.
PHP code
<?php
if($_SERVER['REQUEST_METHOD']=='POST')
{
//Getting values
$username = $_POST['username'];
require_once('dbConnect.php');
$sql = "SELECT * FROM `employee` WHERE username='$username'";
$result=mysqli_query($con,$sql);
$row = mysqli_fetch_array($result,MYSQLI_ASSOC);
echo json_encode($row);
}
Android Retrieve code
#Override
protected String doInBackground(Void... params) {
// TODO: attempt authentication against a network service.
HashMap<String,String> params1= new HashMap<>();
params1.put(Config.KEY_EMP_UN,mUsername);
RequestHandler rh = new RequestHandler();
String res = rh.sendPostRequest(Config.URl_RET, params1);
return res;
// TODO: register the new account here.
}
#Override
protected void onPostExecute(final String success) {
Toast.makeText(Main2Activity.this,success,Toast.LENGTH_LONG).show();
final TextView Textview1 = (TextView)findViewById(R.id.textView);
Textview1.setText(success);
}
This retrieves info in format shown in below image
What is want to do is extract Name,Designation,Salary,Password and display them in separate TextView.How can I do that?

Take your server response and parse it like this
try {
JSONObject jsonObject = new JSONObject(response);
if (jsonObject.has("name")) {
String name=jsonObject.getString("name");
}
if (jsonObject.has("designation")) {
String designation=jsonObject.getString("designation");
}
if (jsonObject.has("salary")) {
int salary=jsonObject.getInt("salary");
}
if(jsonObject.has("password")){
String password=jsonObject.getString("password");
}
}catch (Exception e) {
}

you have to parse the json :
JSONObject jsonObject=new JSONObject(success);
//key value for eg : name,salary etc
// now do whatever you want to do
jsonObject.getString("your key value");

There are lots of possible duplicates to this question, so I recommend closing this question after reading this answer.
What you have in here is a JSON response and in order to parse information in JSON, you have to use a JSON parser. Libraries like Gson, Jackson, Moshi will be able to do this.
If you're using Gson, you have to generate model classes of the response which can be written manually or auto-generated using jsonschema2pojo. Once Gson parses your JSON, you can use your model classes getters to access data.
Links to tutorials
https://kylewbanks.com/blog/Tutorial-Android-Parsing-JSON-with-GSON
Youtube video
https://www.youtube.com/watch?v=y96VcLgOJqA

Convert JSON String to Dictionary in Android

I have the following json formatted string that is returned from the web service:
{"Success":false,"Message":"This version is not supported"}
I am using the following code to invoke the web service:
AsyncHttpClient client = new AsyncHttpClient();
client.get("http://mywebsite/check/getcompatibilityinfo", new AsyncHttpResponseHandler() {
#Override
public void onSuccess(String response) {
System.out.println(response);
}
});
The response contains the json string now I need to access the Success and the Message property. Is there any simple way to do it without using complicated third party libraries?

The JSONObject class is already available in your Android codebase (no 3rd party dependencies). Since your example uses normal (simple) JSON, you can use:
try {
JSONObject responseJSON = new JSONObject(response);
} catch (JSONException e) {
e.printStackTrace();
}
boolean success = responseJSON.getBoolean("Success");
String message = responseJSON.getString("Message");

Convert Twitter4j Status to JSON Object

Android 2.3.3
I am integrating Twitter API into my android application. I am using Twitter4j.
I could get the tweets for a particular user, using the below code.
Paging paging = new Paging(1, 40);
List<twitter4j.Status> statuses = twitter.getUserTimeline("xxx", paging);
Log.d(Const.TAG,"Showing Timeline.");
for (twitter4j.Status status : statuses) {
String rawJSON = DataObjectFactory.getRawJSON(status);
}
My requirement is that I need to parse the JSON String (rawJSON), to get some other values like, published date and so on.
I am pretty new to JSON parsing esp., with converting things to JSON. All i know in the above code is that, String rawJSON = DataObjectFactory.getRawJSON(status); converts the Status Object to a String and I can view it by logging it.
How do I convert this String to a JSONObject or a JSONArray? Can someone provide me with a sample code?
I tried the below code, but it gives an exception
try {
JSONObject tweet = new JSONObject(rawJSON);
JSONArray textArray = tweet.getJSONArray("text");
String text = textArray.getString(0);
Log.d(Const.TAG, "Text = "+text);
} catch (JSONException e) {
// TODO Auto-generated catch block
Log.d(Const.TAG, "Error while converting string to json");
e.printStackTrace();
}

Here's my code to parse a Twitter4j Status. This example get the language of the tweet.
//Status To JSON String
String statusJson = DataObjectFactory.getRawJSON(status);
//JSON String to JSONObject
JSONObject JSON_complete = new JSONObject(statusJson);
//We get another JSONObject
JSONObject JSON_user = JSON_complete.getJSONObject("user");
//We get a field in the second JSONObject
String languageTweet = JSON_user.getString("lang");

I got a way to get values from Status object without the need to convert it into JSON. Of course this is very basic, by I overlooked it.People who have trouble getting values from Status object, can look at this.
You can get all the values by using the object of Status.
For example, if "status" is an object of Status, we can get the text of the tweet, by using, status.getText() and the user value by using status.user() and so on. Just work on the status object a bit and you will find all the values you need.

Sending and Parsing JSON Objects in Android [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 5 years ago.
Improve this question
I would like to send messages in the form of JSON objects to a server and parse the JSON response from the server.
Example of JSON object
{
"post": {
"username": "John Doe",
"message": "test message",
"image": "image url",
"time": "current time"
}
}
I am trying to parse the JSON manually by going attribute by attribute. Is there any library/utility I can use to make this process easier?

I am surprised these have not been mentioned: but instead of using bare-bones rather manual process with json.org's little package, GSon and Jackson are much more convenient to use. So:
GSON
Jackson
So you can actually bind to your own POJOs, not some half-assed tree nodes or Lists and Maps.
(and at least Jackson allows binding to such things too (perhaps GSON as well, not sure), JsonNode, Map, List, if you really want these instead of 'real' objects)
EDIT 19-MAR-2014:
Another new contender is Jackson jr library: it uses same fast Streaming parser/generator as Jackson (jackson-core), but data-binding part is tiny (50kB). Functionality is more limited (no annotations, just regular Java Beans), but performance-wise should be fast, and initialization (first-call) overhead very low as well.
So it just might be good choice, especially for smaller apps.

You can use org.json.JSONObject and org.json.JSONTokener. you don't need any external libraries since these classes come with Android SDK

GSON is easiest to use and the way to go if the data have a definite structure.
Download gson.
Add it to the referenced libraries.
package com.tut.JSON;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
public class SimpleJson extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String jString = "{\"username\": \"tom\", \"message\": \"roger that\"} ";
GsonBuilder gsonb = new GsonBuilder();
Gson gson = gsonb.create();
Post pst;
try {
pst = gson.fromJson(jString, Post.class);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Code for Post class
package com.tut.JSON;
public class Post {
String message;
String time;
String username;
Bitmap icon;
}

This is the JsonParser class
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
Note: DefaultHttpClient is no longer supported by sdk 23, so it is advisable to use target sdk 21 with this code.

There's not really anything to JSON. Curly brackets are for "objects" (associative arrays) and square brackets are for arrays without keys (numerically indexed). As far as working with it in Android, there are ready made classes for that included in the sdk (no download required).
Check out these classes:
http://developer.android.com/reference/org/json/package-summary.html

Other answers have noted Jackson and GSON - the popular add-on JSON libraries for Android, and json.org, the bare-bones JSON package that is included in Android.
But I think it is also worth noting that Android now has its own full featured JSON API.
This was added in Honeycomb: API level 11.
This comprises
- android.util.JsonReader: docs, and source
- android.util.JsonWriter: docs, and source
I will also add one additional consideration that pushes me back towards Jackson and GSON: I have found it useful to use 3rd party libraries rather then android.* packages because then the code I write can be shared between client and server. This is particularly relevant for something like JSON, where you might want to serialize data to JSON on one end for sending to the other end. For use cases like that, if you use Java on both ends it helps to avoid introducing android.* dependencies.
Or I guess one could grab the relevant android.* source code and add it to your server project, but I haven't tried that...

You can download a library from http://json.org (Json-lib or org.json) and use it to parse/generate the JSON

you just need to import this
import org.json.JSONObject;
constructing the String that you want to send
JSONObject param=new JSONObject();
JSONObject post=new JSONObject();
im using two object because you can have an jsonObject within another
post.put("username(here i write the key)","someusername"(here i put the value);
post.put("message","this is a sweet message");
post.put("image","http://localhost/someimage.jpg");
post.put("time": "present time");
then i put the post json inside another like this
param.put("post",post);
this is the method that i use to make a request
makeRequest(param.toString());
public JSONObject makeRequest(String param)
{
try
{
setting the connection
urlConnection = new URL("your url");
connection = (HttpURLConnection) urlConnection.openConnection();
connection.setDoOutput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-type", "application/json;charset=UTF-8");
connection.setReadTimeout(60000);
connection.setConnectTimeout(60000);
connection.connect();
setting the outputstream
dataOutputStream = new DataOutputStream(connection.getOutputStream());
i use this to see in the logcat what i am sending
Log.d("OUTPUT STREAM " ,param);
dataOutputStream.writeBytes(param);
dataOutputStream.flush();
dataOutputStream.close();
InputStream in = new BufferedInputStream(connection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
result = new StringBuilder();
String line;
here the string is constructed
while ((line = reader.readLine()) != null)
{
result.append(line);
}
i use this log to see what its comming in the response
Log.d("INPUTSTREAM: ",result.toString());
instancing a json with the String that contains the server response
jResponse=new JSONObject(result.toString());
}
catch (IOException e) {
e.printStackTrace();
return jResponse=null;
} catch (JSONException e)
{
e.printStackTrace();
return jResponse=null;
}
connection.disconnect();
return jResponse;
}

if your are looking for fast json parsing in android than i suggest you a tool which is freely available.
JSON Class Creator tool
It's free to use and it's create your all json parsing class within a one-two seconds.. :D

Although there are already excellent answers are provided by users such as encouraging use of GSON etc. I would like to suggest use of org.json. It includes most of GSON functionalities. It also allows you to pass json string as an argument to it's JSONObject and it will take care of rest e.g:
JSONObject json = new JSONObject("some random json string");
This functionality make it my personal favorite.

There are different open source libraries, which you can use for parsing json.
org.json :- If you want to read or write json then you can use this library.
First create JsonObject :-
JSONObject jsonObj = new JSONObject(<jsonStr>);
Now, use this object to get your values :-
String id = jsonObj.getString("id");
You can see complete example here
Jackson databind :- If you want to bind and parse your json to particular POJO class, then you can use jackson-databind library, this will bind your json to POJO class :-
ObjectMapper mapper = new ObjectMapper();
post= mapper.readValue(json, Post.class);
You can see complete example here