來源：我的學習筆記

/*先將自己的電腦聯網*/

1.page1

<uses-permission android:name="android.permission.INTERNET" />

2.page2

package com.example.自己的包名;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.widget.Toast;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class MainActivity extends AppCompatActivity {

? ?@Override
? ?protected void onCreate(Bundle savedInstanceState) {
? ? ? ?super.onCreate(savedInstanceState);
? ? ? ?setContentView(R.layout.activity_main);
? ? ? ?NetThread netThread=new NetThread();
? ? ? ?netThread.start();
? ??

? ?}
}

3.page3

package com.example.自己的包名;

import android.util.Log;
import android.widget.Toast;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;



public class NetThread {
? ?public void start(){
? ?try {
? ? ? ?URL url=new URL("https://baidu.com");
? ? ? ?HttpURLConnection conn=(HttpURLConnection) url.openConnection();
? ? ? ?//Toast.makeText(this,"網絡成功",Toast.LENGTH_SHORT).show();
? ? ? ?conn.setRequestMethod("GET");
? ? ? ?conn.setConnectTimeout(10000);
? ? ? ?InputStream is =conn.getInputStream();
? ? ? ?conn.disconnect();

? ?}catch (Exception ex){
? ? ? ?//Toast.makeText(this,"網絡失敗",Toast.LENGTH_SHORT).show();
? ? ? /* 調試工具*/
? ? ? ?Log.i("abcd","網絡錯誤");



? ?}


? ?}

}