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Учуcь программировать на Android, IOS и Unity.

Как сформировать HTTP GET запрос, чтобы заполнить главную activity?

Скрипт на сервере формирует JSON строку и отправляет её. Приложение должно получить её, обработать и сформировать Adapter для RecyclerView. Как это лучше сделать? Этот код не работает, с сервера не приходит ответ:

MainActivity.java
spoiler
package /*pkgname*/;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;


import com.google.gson.Gson;



import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import javax.net.ssl.HttpsURLConnection;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {
    ArrayList<News> news;


    String result = new String();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        LinearLayoutManager layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.addItemDecoration(new SpaceItemDecoration(1));
        news = getNews();
        NewsAdapter newsAdapter = new NewsAdapter(news);
        recyclerView.setAdapter(newsAdapter);
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);

    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_camera) {
            // Handle the camera action
        } else if (id == R.id.nav_gallery) {

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }

    public ArrayList<News> getNews() {
        Gson jsoner = new Gson();
        ArrayList<News> newsArrayList = new ArrayList<>();
        News[] news;
        AsyncGet asyncGet = new AsyncGet();
        asyncGet.execute();
        try {
            news = jsoner.fromJson(asyncGet.get(3, TimeUnit.SECONDS), News[].class);
            for (int i = 0; i < news.length; i++) newsArrayList.add(news[i]);
        } catch (Exception e) {
        }
        return newsArrayList;
    }


    class AsyncGet extends AsyncTask<String, Integer, String> {

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            result = s;
        }

        @Override
        protected String doInBackground(String... strings) {
            InputStream stream = null;
            HttpURLConnection connection = null;
            try {
                connection = (HttpURLConnection) new URL("http:// /*sitepath*/ uploaderl.php?action=get").openConnection();
                // Timeout for reading InputStream arbitrarily set to 3000ms.
                connection.setReadTimeout(3000);
                // Timeout for connection.connect() arbitrarily set to 3000ms.
                connection.setConnectTimeout(3000);
                // For this use case, set HTTP method to GET.
                connection.setRequestMethod("GET");
                // Already true by default but setting just in case; needs to be true since this request
                // is carrying an input (response) body.
                connection.setDoInput(true);
                // Open communications link (network traffic occurs here).
                connection.connect();
                int responseCode = connection.getResponseCode();
                if (responseCode != HttpsURLConnection.HTTP_OK) {
                    throw new IOException("HTTP error code: " + responseCode);
                }
                // Retrieve the response body as an InputStream.
                stream = connection.getInputStream();

                if (stream != null) {
                    // Converts Stream to String with max length of 500.
                    result = readStream(stream, Integer.MAX_VALUE);
                }
            } catch (Exception e) {
            } finally {
                // Close Stream and disconnect HTTPS connection.
                if (stream != null) {
                    try {
                        stream.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (connection != null) {
                    connection.disconnect();
                }
            }
            return result;
        }
    }


    public String readStream(InputStream stream, int maxReadSize)
            throws IOException, UnsupportedEncodingException {
        Reader reader = null;
        reader = new InputStreamReader(stream, "UTF-8");
        char[] rawBuffer = new char[maxReadSize];
        int readSize;
        StringBuffer buffer = new StringBuffer();
        while (((readSize = reader.read(rawBuffer)) != -1) && maxReadSize > 0) {
            if (readSize > maxReadSize) {
                readSize = maxReadSize;
            }
            buffer.append(rawBuffer, 0, readSize);
            maxReadSize -= readSize;
        }
        return buffer.toString();
    }
}
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