To get the size of file from server first you need to connect to the server using URL and HttpURLConnection Class. To get the size of file we use getContentLength() method. As the size of file can be too large we use BigInteger class. You cannot use integer datatype as it can generate an error in case the size of file is greater than 2Gb.
To know more about BigInteger class refer link: BigInteger class in Java
For HttpURLConnection refer link: Java.net.HttpURLConnection Class in Java
Java
// Java Program to calculate Size// of a file on the Internet.import java.math.BigInteger;import java.net.URL;import java.net.HttpURLConnection;  public class SizeFile {          public static void main(String args[]) throws Exception    {        BigInteger size = new BigInteger("1");          // get the url of web page        URL url = new URL(              // create a connection        HttpURLConnection conn;        try        {                              // open stream to get size of page            conn = (HttpURLConnection)url.openConnection();                          // set request method.            conn.setRequestMethod("HEAD");                          // get the input stream of process            conn.getInputStream();                          // store size of file            size = BigInteger.valueOf(conn.getContentLength());                          // print the size of downloaded file            System.out.println("The Size of file is:" +                                       size + " bytes");            conn.getInputStream().close();        }        catch (Exception e)        {            System.out.println("Connection failed");        }    }} |
