使用AsyncTask+HttpURLConnection请求数据

/**
* 使用AsyncTask+HttpURLConnection请求数据
* Created by e531 on 2017/10/12.
*/
public class MyTask extends AsyncTask<String,Void,String> {

//申请一个接口类对象
private  Icallbacks icallbacks;

//将无参构造设置成私有的，使之在外部不能够调用
private MyTask(){}

//定义有参构造方法
public MyTask(Icallbacks icallbacks) {
this.icallbacks = icallbacks;
}

@Override
protected String doInBackground(String... params) {
String str="";

try {
//使用HttpUrlConnection
URL url=new URL(params[0]);
HttpURLConnection connection=(HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setReadTimeout(5000);
connection.setConnectTimeout(5000);

if(connection.getResponseCode()==200){
InputStream inputStream=connection.getInputStream();
//调用工具类中的静态方法
str=StreamToString.streamToStr(inputStream,"utf-8");
}

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

return str;
}

@Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
//解析，封装到bean,更新ui组件
icallbacks.updateUiByjson(s);

}
//定义一个接口
public interface Icallbacks{
/**
* 根据回传的json字符串，解析并更新页面组件
* @param jsonstr
*/
void updateUiByjson(String jsonstr);
}
}