HttpURLConnection基本工作原理

运行截图

MainActivity.java

package csdn.example.com.notification.NetWorkTest;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import csdn.example.com.notification.R;

public class Main6Activity extends AppCompatActivity implements View.OnClickListener {
    TextView request_text;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main6);
        request_text = (TextView) findViewById(R.id.request_text);
        Button send_Request = (Button) findViewById(R.id.send_request);
        send_Request.setOnClickListener(this);

    }


    @Override
    public void onClick(View v) {
        if(v.getId() == R.id.send_request){
            Log.d("T","没毛病,老铁");
            sendRequestWithHttpURLConnection();
        }
    }

    private void sendRequestWithHttpURLConnection() {
        new Thread(new Runnable() {

            @Override
            public void run() {
                HttpURLConnection connection = null;
                BufferedReader reader = null;
                try {
                    URL url = new 
                    connection = (HttpURLConnection) url.openConnection();
                    connection.setRequestMethod("GET");
                    connection.setConnectTimeout(8000);
                    connection.setReadTimeout(8000);
                    InputStream in = connection.getInputStream();
                    reader = new BufferedReader(new InputStreamReader(in));
                    String line;
                    StringBuilder reaponse = new StringBuilder();
                    Log.d("T","没毛病,老铁2");
                    Integer count = 0;
                    while ((line=reader.readLine())!=null){
                        count++;
                        line = "第"+count+"行代码为: "+line+"\n\n";
                        reaponse.append(line);

                    }
                    showResponse(reaponse.toString());
                } catch (Exception e) {
                    e.printStackTrace();
                }finally {
                    if(reader!=null){
                        try {
                            reader.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    if(connection!=null){
                        connection.disconnect();
                    }
                }
            }
        }).start();
    }

    private void showResponse(final String response) {
       runOnUiThread(new Runnable() {
           @Override
           public void run() {
               Log.d("T","没毛病,老铁1"+response);
               request_text.setText(response);
           }
       });
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/send_request"
        android:text="发送请求"
        />
    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <TextView
            android:id="@+id/request_text"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </ScrollView>
</LinearLayout>

清单文件AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="csdn.example.com.notification">

    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <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">
        <provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="csdn.example.com.notification.CameraAlbumTest"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_paths" />
        </provider>
        <activity android:name=".NetWorkTest.Main6Activity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>

</manifest>