简单Android HttpURLConnection---Get方式

Android 使用Http 链接获取数据的方式有两种 一个是HttpURLConnection 另一个是HttpClient。

每一种都有两种传输方式：GET 和 POST；（另外还有专门的HttpGet 和HttpPost 方式）

其二者区别：

1. GET请求请提交的数据放置在HTTP请求协议头中(http://www.xxx.com/xxx?action="xxx"&action2="xxx");而POST提交的数据则放在实体数据中(使用NameValuePair来保存要传递的Post参数)；
2. GET方式提交的数据最多只能有1024字节，而POST则没有此限制；

这里主要介绍 HttpConnection 的子类 HttpURLConnection；

核心代码：

URL url = new URL(urlString);  
        HttpURLConnection urlConn=(HttpURLConnection)url.openConnection();
        //设置超时时间
        urlConn.setConnectTimeout(1000);
        //链接状态
        int code = urlConn.getResponseCode();
        if(code == HttpURLConnection.HTTP_OK){
             //得到读取的内容(流)  
            InputStreamReader in = new InputStreamReader(urlConn.getInputStream());  
            // 为输出创建BufferedReader  
            BufferedReader buffer = new BufferedReader(in);  
            String inputLine = null;  
            //使用循环来读取获得的数据  
            while (((inputLine = buffer.readLine()) != null))  
            {  
                //我们在每一行后面加上一个"\n"来换行  
                resultData += inputLine + "\n";  
            }    
            //关闭InputStreamReader  
            in.close(); 
        }
        //关闭http连接  
        urlConn.disconnect();                

这个是HttpURLConnection 的Get的方式，无需设置，默认为Get方式，如要Post方式则 setDoOutput(ture) ,其他方式(OPTIONS, HEAD, PUT, DELETEand TRACE) 则使用setRequestMethod(String).

全部代码：

public class HttpConnActivity extends Activity {
    
      String googleWeatherUrl2 = "http://m.weather.com.cn/data/101010100.html";
    private String resultData = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_json);
        Thread mThread = new Thread(GetWeatherDataThread);
        mThread.start();
    }
    
    private Runnable  GetWeatherDataThread = new Runnable() {
        
        @Override
        public void run() {
            // TODO Auto-generated method stub
            try {
                getWeatherData();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            mHandler.sendEmptyMessage(0);
        }
    };
    
    Handler mHandler = new Handler(){

        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            super.handleMessage(msg);
            if(msg.what == 0){
                System.out.println(resultData);
                System.out.println("线程结束");
            }
        }
        
    };
    
    public void getWeatherData() throws IOException {
        URL url = new URL(googleWeatherUrl2);  
        HttpURLConnection urlConn=(HttpURLConnection)url.openConnection();
        urlConn.setConnectTimeout(1000);
        int code = urlConn.getResponseCode();
        if(code == HttpURLConnection.HTTP_OK){
             //得到读取的内容(流)  
            InputStreamReader in = new InputStreamReader(urlConn.getInputStream());  
            // 为输出创建BufferedReader  
            BufferedReader buffer = new BufferedReader(in);  
            String inputLine = null;  
            //使用循环来读取获得的数据  
            while (((inputLine = buffer.readLine()) != null))  
            {  
                //我们在每一行后面加上一个"\n"来换行  
                resultData += inputLine + "\n";  
            }    
            //关闭InputStreamReader  
            in.close(); 
        }
        //关闭http连接  
        urlConn.disconnect();
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_json, menu);
        return true;
    }
}