This is my current code. I can compile it but the output is and error. The purpose of this is to download pdb files from PDB's ftp site. Can anyone enlighten me on this please? Your help is much appreciated(:

import java.io.*;
import java.net.URL;
import java.net.URLConnection;
import java.io.FileOutputStream;


public class ftp {

    public static void main(String[] args) {

        try{

    URL url =     new URL("ftp://ftp.ww.pdb.org//pub//pdb//data//structures//all//pdb//pdb100d.ent.gz;type=i");
    URLConnection con = url.openConnection();

    BufferedInputStream in =     new BufferedInputStream(con.getInputStream());
    FileOutputStream out =     new FileOutputStream("C:\\Users\\Royston\\Documents\\FTP downloads\\pdb100d.ent.gz");

    int i = 0;
    byte[] bytesIn = new byte[1024];

    while ((i = in.read(bytesIn)) >= 0)
     {
    out.write(bytesIn, 0, i);
     }
    out.close();
    in.close();
        } catch(Exception e)
        {
            e.printStackTrace();
        }    
    }   
}

The error I'm getting is this :

java.net.UnknownHostException: ftp.ww.pdb.org
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
    at java.net.Socket.connect(Socket.java:525)
    at java.net.Socket.connect(Socket.java:475)
    at sun.net.NetworkClient.doConnect(NetworkClient.java:163)
    at sun.net.NetworkClient.openServer(NetworkClient.java:118)
    at sun.net.ftp.FtpClient.openServer(FtpClient.java:488)
    at sun.net.ftp.FtpClient.openServer(FtpClient.java:475)
    at sun.net.www.protocol.ftp.FtpURLConnection.connect(FtpURLConnection.java:270)
    at sun.net.www.protocol.ftp.FtpURLConnection.getInputStream(FtpURLConnection.java:352)
    at ftp.main(ftp.java:25)

Process completed.