HttpUrlConnection的get用法

第一个项目关于HttpUrlConnection的get方法。

HttpUrlConnection是java.net包下的。是java自带的。

<pre name="code" class="java">package com.example.dugaolong.httpurlconnectiondemo;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
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.MalformedURLException;
import java.net.URL;

/**
 * 标准Java接口(java.net) ----HttpURLConnection，可以实现简单的基于URL请求、响应功能；
 * <p>
 * HttpUrlConnection
 * get
 * <p>
 */
public class MainActivity extends Activity {
    private final String TAG = this.getClass().getSimpleName();

    private TextView textView;
    private Handler mHandler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //在ui线程中定义handler
        mHandler = new Handler(){
            @Override
            public void handleMessage(Message msg) {
                if (msg.what == 1){
                    textView.setText(msg.obj.toString());
                }
            }

        };

        Button button = (Button) findViewById(R.id.bt_get);
        textView = (TextView) findViewById(R.id.tv_message);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                getHttpUrlConnection();
            }
        });
    }

    /**
     * get方式请求网络
     */
    private void getHttpUrlConnection() {
        final String getUrl = "http://172.16.150.71:8080/http/servlet/Http?sex=girl";
        //请求网络必须要开新的子线程
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    URL url = new URL(getUrl);//URL对象
                    HttpURLConnection conn = (HttpURLConnection) url.openConnection();//使用URL打开一个链接
                    conn.setDoInput(true);
                    //接收返回结果
                    if (conn.getResponseCode() == 200) {
                        //读取返回的流信息
                        InputStream is = conn.getInputStream();
                        BufferedReader br = new BufferedReader(new InputStreamReader(is));
                        StringBuffer sb = new StringBuffer();
                        String readLine = "";
                        while ((readLine = br.readLine()) != null) {//一行一行读取
                            sb.append(readLine);
                        }
                        //另外一种读取流内容的方法
//                        InputStream in = conn.getInputStream();
//                        byte[] b = new byte[4096];
//                        StringBuffer out = new StringBuffer();
//                        for (int n; (n = in.read(b)) != -1; ) {
//                            out.append(new String(b, 0, n));
//                        }
//                        textView.setText(sb.toString());
                        //关闭流
                        is.close();
                        br.close();
                        conn.disconnect();
                        Message msg = new Message();
                        msg.what=1;
                        msg.obj=sb.toString();
                        mHandler.sendMessage(msg);
                        Log.i(TAG, "reaponse:" + sb.toString());

                    }


                } catch (MalformedURLException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }


            }
        }).start();
    }

    //另外一种写法
    class MyHandler extends Handler {

        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            if (msg.what == 1){
                textView.setText(msg.obj.toString());
            }
        }
    }


}

activity_main.xml文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <Button
        android:id="@+id/bt_get"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="doGet"/>


    <TextView
        android:id="@+id/tv_message"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

记得在manifest文件中添加权限。

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

HttpUrlConnection的get方式简单只要在url中拼接参数就ok。