Problem when showing a json from my localhost

I am developing a app in which I want to connect said app to a api . But I'm having problems receiving the json to be able to show it within my app . I share the code.

MainActivity

public class MainActivity extends Activity {

    EditText etResponse;
    TextView tvIsConnected;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // get reference to the views
        etResponse = (EditText) findViewById(R.id.etResponse);
        tvIsConnected = (TextView) findViewById(R.id.tvIsConnected);

        // check if you are connected or not
        if(isConnected()){
            tvIsConnected.setBackgroundColor(0xFF00CC00);
            tvIsConnected.setText("You are conncted");
        }
        else{
            tvIsConnected.setText("You are NOT conncted");
        }

        // call AsynTask to perform network operation on separate thread
        new HttpAsyncTask().execute("http://localhost/usuario/");
    }

    public static String GET(String url){
        InputStream inputStream = null;
        String result = "";
        try {

            // create HttpClient
            HttpClient httpclient = new DefaultHttpClient();

            // make GET request to the given URL
            HttpResponse httpResponse = httpclient.execute(new HttpGet(url));

            // receive response as inputStream
            inputStream = httpResponse.getEntity().getContent();

            // convert inputstream to string
            if(inputStream != null)
                result = convertInputStreamToString(inputStream);
            else
                result = "Did not work!";

        } catch (Exception e) {
            Log.d("InputStream", e.getLocalizedMessage());
        }

        return result;
    }

    private static String convertInputStreamToString(InputStream inputStream) throws IOException{
        BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
        String line = "";
        String result = "";
        while((line = bufferedReader.readLine()) != null)
            result += line;

        inputStream.close();
        return result;

    }

    public boolean isConnected(){
        ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected())
            return true;
        else
            return false;
    }
    private class HttpAsyncTask extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... urls) {

            return GET(urls[0]);
        }
        // onPostExecute displays the results of the AsyncTask.
        @Override
        protected void onPostExecute(String result) {
            Toast.makeText(getBaseContext(), "Received!", Toast.LENGTH_LONG).show();
            etResponse.setText(result);

        }
    }
}

Activity_main

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/tvIsConnected"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:background="#FF0000"
        android:textColor="#FFF"
        android:textSize="18dp"
        android:layout_marginBottom="5dp"
        android:text="is connected? " />

    <EditText
        android:id="@+id/etResponse"
        android:layout_width="match_parent"
        android:layout_height="fill_parent"
        android:ems="10"
        android:layout_marginTop="10dp"
        android:inputType="textMultiLine" >\
        <requestFocus />
    </EditText>
</LinearLayout>

The json q I try to show in my app