"Any fool can write code that a computer can understand. Good programmers write code that humans can understand." --- Martin Fowler
Please correct my English.
Is this server the local machine or a remote server? If it's the local machine it's as easy as using java.io.File, as Wouter suggested. If it's a remote server it depends on which protocols are available. You can use SMB (Windows sharing), FTP, NFS, or possibly even something completely custom.