Android Studio, http request error(?)

I am a newbie to Android Studio and have been under this problem for a few days. My code is simple, which requests the information of the website that I specify when I push a button and get the response from that website. The problem is that my android app can not connect to the website by using 'httpurlconnection' class.

Here are the things that I tried to fix this problem. 1. Recreate AVD (it didn't work). 2. Remove some of image files because my error message was "skipped frames the application may be doing too much work on its main thread".

Here is my code below. I think it does not seem to have any problems in the below code because I coded the below code, following the lectures on youtube. So I guess this issue might be on configure / setting mode. Anyone know how to fix this..?

Thanks in advance.

• Manifest

  <?xml version="1.0" encoding="utf-8"?>
  <manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.lhc.test_1">
  
      <uses-permission android:name="android.permission.INTERNET"/>
  
      <application
          android:allowBackup="true"
          android:icon="@mipmap/ic_launcher"
          android:label="@string/app_name"
          android:roundIcon="@mipmap/ic_launcher_round"
          android:supportsRtl="true"
          android:theme="@style/AppTheme">
          <activity android:name=".MainActivity">
              <intent-filter>
                  <action android:name="android.intent.action.MAIN" />
  
                  <category android:name="android.intent.category.LAUNCHER" />
              </intent-filter>
          </activity>
      </application>
  
  </manifest>
  
  

• MainActivity.java

  package com.example.lhc.test_1;
  
  import android.os.Handler;
  import android.support.v7.app.AppCompatActivity;
  import android.os.Bundle;
  import android.view.View;
  import android.widget.Button;
  import android.widget.TextView;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.net.HttpURLConnection;
  import java.net.URL;
  
  public class MainActivity extends AppCompatActivity {
  
      public static final String TAG = "MainActivity";
      Handler handler;
      TextView text01;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          text01 = (TextView)findViewById(R.id.text01);
  
          final Button requestButton = (Button)findViewById(R.id.requestButton);
          requestButton.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View view) {
                  request();
              }
          });
  
          handler = new Handler();
      }
  
      private void request() {
  
          try {
              URL url = new URL("http://m.google..com"); // 페이지 정보 저장
              HttpURLConnection conn = (HttpURLConnection) url.openConnection(); // 연결
  
              if(conn != null) {
                  conn.setRequestMethod("GET");
                  conn.setDoInput(true);
                  conn.setDoOutput(true);
                  conn.setConnectTimeout(10000);
  
                  int resCode = conn.getResponseCode(); // 연결 요청 및 정보 요청
                  if(resCode == HttpURLConnection.HTTP_OK) {
                      BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
  
                      while(true) {
                          String aLine = reader.readLine();
                          if(aLine == null) {
                              break;
                          }
  
                          appendText(aLine);
                      }
                      reader.close();
                  }
                  conn.disconnect();
              }
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  
      private void appendText(String msg) {
          final String inMsg = msg;
          handler.post(new Runnable() {
              @Override
              public void run() {
                  text01.append(inMsg + "\n");
              }
          });
      }
  }
  
  

• activity.xml

  <?xml version="1.0" encoding="utf-8"?>
  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      tools:context=".MainActivity">
  
      <Button
          android:id="@+id/requestButton"
          android:layout_margin="20dp"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_gravity="center_horizontal"
          android:text="요청"
          />
  
      <TextView
          android:id="@+id/text01"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="ttt"
          android:background="#ffffff"
          android:textSize="16dp"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintLeft_toLeftOf="parent"
          app:layout_constraintRight_toRightOf="parent"
          app:layout_constraintTop_toTopOf="parent"/>
  
  </LinearLayout>