HTTP通信（HttpURLConnection）

Android发送HTTP请求有两种，HttpURLConnection和HttpClient

用法：

1.获取HttpURLConnection实例

new一个URL对象，传入一个网络地址；然后调用openConnection方法

 

2.设置HTTP请求的方法

常用的方法有两种：GET和POST方法，GET：从服务器获取数据；POST：发送数据给服务器

 

3.设置一些东西

比如设置连接超时，读取超时，服务器希望得到的消息头等

 

4.getInputStream获取服务器返回的输入流

 

5.对输入流进行读取

 

6.disconnect关闭HTTP连接

---

private void sendResquestWithURLConnection(){
new Thread(new Runnable() {
@Override
public void run() {
            HttpURLConnection connection = null;
try{
                URL url = new URL("http://www.baidu.com");
                connection = (HttpURLConnection) url.openConnection();

                connection.setRequestMethod("GET");

                connection.setConnectTimeout(8000);
                connection.setReadTimeout(8000);

                InputStream in = connection.getInputStream();

                BufferedReader reader = new BufferedReader(new InputStreamReader(in));
                StringBuilder response = new StringBuilder();
                String line;
while((line = reader.readLine()) != null){
                    response.append(line);
                }
                Message message = new Message();
                message.what = SHOW_RESPONSE;

                message.obj = response.toString();
handler.sendMessage(message);
            }catch(Exception e){
                e.printStackTrace();
            }finally{
if (connection != null){
                    connection.disconnect();
                }
            }
        }
    }).start();

---

private Handler handler = new Handler(){
@Override
public void handleMessage(Message msg) {
switch (msg.what){
case SHOW_RESPONSE:
                String response = (String)msg.obj;
              responseText.setText(response);
        }

    }
};

---

@Override

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    sendRequest = (Button) findViewById(R.id.send_request);
    responseText = (TextView) findViewById(R.id.response_text);
    sendRequest.setOnClickListener(this);
}

@Override
public void onClick(View v) {
if (v.getId() == R.id.send_request){
        sendResquestWithURLConnection();
    }
}