The ftp4j library implements a Java full-featured FTP client. With ftp4j embedded in your application you can: transfer files (upload and download), browse the FTP site (directory listing), create, delete, rename and move directories and files.
Programmatically controllable FTP client written in the Java language that targets any network oriented standalone application, and even applet, that needs to rely on FTP to exchange files over a network. Should replace the cryptic sun.net.ftp.* classes.