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MainActivity.java

package in.apptonic.lalit.newsarticlesample;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.TextView;

import net.minidev.json.JSONArray;
import net.minidev.json.JSONObject;
import net.minidev.json.JSONValue;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;

import javax.net.ssl.HttpsURLConnection;

public class MainActivity extends AppCompatActivity {

    private TextView resultTextView;
    private ArrayList<NewsArticleHolder.ArticleItem> articleItems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        resultTextView = (TextView) this.findViewById(R.id.result);

        NewsAPIAsyncTask getNewsUpdate = new NewsAPIAsyncTask();
        getNewsUpdate.execute();

        resultTextView.setText((CharSequence) articleItems);

    }


    public class NewsAPIAsyncTask extends AsyncTask<Void, Void, ArrayList<NewsArticleHolder.ArticleItem>> {

        InputStream inputStream = null;

        @Override
        protected ArrayList<NewsArticleHolder.ArticleItem> doInBackground(Void... params) {
            String result = "";

            //connection to url

            URL url = null;
            try {
                url = new URL("https://newsapi.org/v1/articles?source=mashable&sortBy=top&apiKey=eff7c7c5b2b7470e9f785483a9d9520b");
            } catch (MalformedURLException e) {
                e.printStackTrace();
            }

            HttpsURLConnection urlConnection = null;
            try {
                urlConnection = (HttpsURLConnection) url.openConnection();
            } catch (IOException e) {
                e.printStackTrace();
            }

            //pulling data from link

            try {
                inputStream = new BufferedInputStream(urlConnection.getInputStream());
            } catch (IOException e) {
                e.printStackTrace();
            }

                BufferedReader bufferReader = new BufferedReader(new InputStreamReader(inputStream));

            String line;

            try {
                while ((line = bufferReader.readLine()) != null) {

                    result += line;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }

            Log.e("", "result" + result);

            JSONObject jsonObject = null;

            if (JSONValue.isValidJson(result)) {

                jsonObject = (JSONObject) JSONValue.parse(result);
            }

            JSONArray stories = (JSONArray) jsonObject.get("articles");

            String[] JSONKey = MainActivity.this.getResources().getStringArray(R.array.NewsAPIJSONKey);


            ArrayList<NewsArticleHolder.ArticleItem> articleItems = new ArrayList<>();

            for (int i = 0; i < stories.size(); i++) {

                JSONObject entry = (JSONObject) stories.get(i);

                NewsArticleHolder.ArticleItem temp = new NewsArticleHolder.ArticleItem(

                        (String) entry.get(JSONKey[0]),
                        (String) entry.get(JSONKey[1]),
                        (String) entry.get(JSONKey[2]),
                        (String) entry.get(JSONKey[3]),
                        (String) entry.get(JSONKey[4]),
                        (String) entry.get(JSONKey[5])
                );

                articleItems.add(temp);
                urlConnection.disconnect();

            }


            return articleItems;
        }

        @Override
        protected void onPostExecute(ArrayList<NewsArticleHolder.ArticleItem> result) {

            MainActivity.this.articleItems = result;

            resultTextView.setText("");
            for (int i =0; i < articleItems.size(); i++){

                resultTextView.append(articleItems + "");
            }

        }
    }

}