ftpclient.java

ftp server and ftp client

import java.net.*;
import java.io.*;
import java.util.*;


class FTPClient
{
	public static void main(String args[]) throws Exception
	{
		Socket soc=new Socket("127.0.0.1",5217);
		transferfileClient t=new transferfileClient(soc);
		t.displayMenu();
		
	}
}
class transferfileClient
{
	Socket ClientSoc;

	DataInputStream din;
	DataOutputStream dout;
	BufferedReader br;
	transferfileClient(Socket soc)
	{
		try
		{
			ClientSoc=soc;
			din=new DataInputStream(ClientSoc.getInputStream());
			dout=new DataOutputStream(ClientSoc.getOutputStream());
			br=new BufferedReader(new InputStreamReader(System.in));
		}
		catch(Exception ex)
		{
		}		
	}
	void SendFile() throws Exception
	{		
		
		String filename;
		System.out.print("Enter File Name :");
		filename=br.readLine();
			
		File f=new File(filename);
		if(!f.exists())
		{
			System.out.println("File not Exists...");
			dout.writeUTF("File not found");
			return;
		}
		
		dout.writeUTF(filename);
		
		String msgFromServer=din.readUTF();
		if(msgFromServer.compareTo("File Already Exists")==0)
		{
			String Option;
			System.out.println("File Already Exists. Want to OverWrite (Y/N) ?");
			Option=br.readLine();			
			if(Option=="Y")	
			{
				dout.writeUTF("Y");
			}
			else
			{
				dout.writeUTF("N");
				return;
			}
		}
		
		System.out.println("Sending File ...");
		FileInputStream fin=new FileInputStream(f);
		int ch;
		do
		{
			ch=fin.read();
			dout.writeUTF(String.valueOf(ch));
		}
		while(ch!=-1);
		fin.close();
		System.out.println(din.readUTF());
		
	}
	
	void ReceiveFile() throws Exception
	{
		String fileName;
		System.out.print("Enter File Name :");
		fileName=br.readLine();
		dout.writeUTF(fileName);
		String msgFromServer=din.readUTF();
		
		if(msgFromServer.compareTo("File Not Found")==0)
		{
			System.out.println("File not found on Server ...");
			return;
		}
		else if(msgFromServer.compareTo("READY")==0)
		{
			System.out.println("Receiving File ...");
			File f=new File(fileName);
			if(f.exists())
			{
				String Option;
				System.out.println("File Already Exists. Want to OverWrite (Y/N) ?");
				Option=br.readLine();			
				if(Option=="N")	
				{
					dout.flush();
					return;	
				}				
			}
			FileOutputStream fout=new FileOutputStream(f);
			int ch;
			String temp;
			do
			{
				temp=din.readUTF();
				ch=Integer.parseInt(temp);
				if(ch!=-1)
				{
					fout.write(ch);					
				}
			}while(ch!=-1);
			fout.close();
			System.out.println(din.readUTF());
				
		}
		
		
	}

	public void displayMenu() throws Exception
	{
		while(true)
		{	
			System.out.println("[ MENU ]");
			System.out.println("1. Send File");
			System.out.println("2. Receive File");
			System.out.println("3. Exit");
			System.out.print("\nEnter Choice :");
			int choice;
			choice=Integer.parseInt(br.readLine());
			if(choice==1)
			{
				dout.writeUTF("SEND");
				SendFile();
			}
			else if(choice==2)
			{
				dout.writeUTF("GET");
				ReceiveFile();
			}
			else
			{
				dout.writeUTF("DISCONNECT");
				System.exit(1);
			}
		}
	}
}