File Empty When Attempt To Transfer Between Computers Using Sockets

I am working on a project with client/server relationship and I want the client to be able to transfer their personal music files over the socket. Every time I attempt to do it the file is created but it is empty.

Server code:

Java Code:

public class Server extends JFrame {
//===============================
// FIELDS
//===============================
// connection essentials
private ServerSocket server;
private Socket connection;

[Code] ....