How to connect server using FTP

Question

hi all,
i have an exception while running this program.
import java.io.*;
import java.net.*;
class FTPclientConn {
public final String host;
public final String user;
protected final String password;
protected URLConnection urlc;
public FTPclientConn(String host, String user, String _password) {
host= host;  user= user; password= _password;
urlc = null;
protected URL makeURL(String targetfile) throws MalformedURLException {
if (user== null)
return new URL("ftp://"+ host+ "/"+ targetfile+ ";type=i");
else
return new URL("ftp://"+ user+ ":"+ password+ "@"+ host+ "/"+ targetfile+ ";type=i");
protected InputStream openDownloadStream(String targetfile) throws Exception {
URL url= makeURL(targetfile);
urlc = url.openConnection();
InputStream is = urlc.getInputStream();
return is;
protected OutputStream openUploadStream(String targetfile) throws Exception {
URL url= makeURL(targetfile);
urlc = url.openConnection();
OutputStream os = urlc.getOutputStream();
return os;
protected void close() {
urlc= null;
public class FTPupload {
protected FTPclientConn cconn;
public final String localfile;
public final String targetfile;
public FTPupload(String host, String user, String _password,
String localfile, String targetfile) {
cconn= new FTPclientConn(_host, user, password);
localfile= _localfile;
targetfile= _targetfile;
doit();
public FTPupload(String host, String user, String password, String file) {
cconn= new FTPclientConn(_host, user, password);
localfile= _file;
targetfile= _file;
doit();
protected void doit() {
try {
OutputStream os= cconn.openUploadStream(targetfile);
FileInputStream is= new FileInputStream(localfile);
byte[] buf= new byte[16384];
int c;
while (true) {
//System.out.print(".");
c= is.read(buf);
if (c<= 0) break;
//System.out.print("[");
os.write(buf, 0, c);
//System.out.print("]");
os.close();
is.close();
cconn.close(); // section 3.2.5 of RFC1738
} catch (Exception E) {
System.err.println(E.getMessage());
E.printStackTrace();
public static void main(String args[]) {
// Usage: FTPupload host, user, password, file
new FTPupload(args[0], args[1], args[2], args[3]);
i gave the input in command prompt: java FTPupload 172.16.2.1 username password filename and also i am getting exception as
D:\ftp>java FTPupload 172.16.2.1 hariraj raj_123 ftpcheck.java
Connection refused: connect
java.net.ConnectException: Connection refused: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(Unknown Source)
at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
how to resolve this problem.thanks in advance.

Answer 1

Connection refused means that you can't reach the server or that the server isn't listening.
Kaj