获取远程文件大小

import java.net.HttpURLConnection;import java.net.URL;        URL url = new URL("http://www.baidu.com/1.jpg");        HttpURLConnection con = (HttpURLConnection) url.openConnection();        long bytesum = 0;        long byteread = 0;        byte[] buffer = new byte[1024];        InputStream inputStream = con.getInputStream();        while ((byteread = inputStream.read(buffer)) != -1) {            bytesum += byteread;        }

//bytesum得到的是byte,除以1024得到KB