HttpUtil

public class Util {
//接口
public interface CallBackString{
void getData(String s);
}
public static void httpAsyn(String strUrl,final CallBackString backString){
new AsyncTask<String,Integer,String>(){
@Override
protected String doInBackground(String… strings) {
return httpGet(strings[0]);
}

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            backString.getData(s);
        }
    }.execute(strUrl);
}
public static boolean isNet(Context context){
    if (context!=null){
        ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
        if (mNetworkInfo!=null){
            return mNetworkInfo.isAvailable();
        }
    }
    return false;
}
public static String httpGet(String strUrl){
    try {
        URL url = new URL(strUrl);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        //设置GET请求
        connection.setRequestMethod("GET");
        connection.setConnectTimeout(5000);
        connection.setReadTimeout(5000);
        //得到数据
        InputStream stream = connection.getInputStream();
        BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
        //拼接数据
        StringBuilder builder = new StringBuilder();
        String str="";
        while((str=reader.readLine())!=null){
             builder.append(str);
        }
        //关闭连接
        connection.disconnect();
        //返回数据
        return builder.toString();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}

}