How to tranfer file from between two client?

Question

Hi, all:
I'd like to tranfer file from client A to client B. Basically, I will treat one of them is client and one of them is server, then create a server socket/socket connection, then they can conmmunicate. I know how to talk between them. However, I don't know how to trasfer file from client to server, or from server to client in the same class. I mean not two class: Server socket and client socket.
Consider the following case:
There is a function, just like MSN file transfer: transfer file from localhost to "10.4.155.8". How can I transfer file from localhost to "10.4.155.8"?
Help please.
--Paul                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

Answer 1

Hi, man:
Thanks.
I agree with you at most.
I am doing my practise project: the other MSN Messenger and more, I will include file encryption and file decryption, etc.
My point is one connection will make center server too heavy. Then I have to adapt your first means:
promote either Client A or Client B become server, leave the other guy still being client, because I know their IP address. This will free the server a lot.
BTW, I finish my code pretty much, say 70%. However, I felt tired for coding. I have my full time job in software development at daytime. I am looking one or two guy to share this project. My point is to improve the performance of the this Messenger. I feel my code maybe work fine with hundred of con-current user, maybe not, or maybe more, not sure. My email: [email protected]. (I put my name means I am searious).
Could anyone feel he/she is good at Messenger, please email me, then we can share my code with you.
Code sample for file transfer:
//For Client side
import java.io.*;
import java.net.*;
class Client
public static void main(String args[]) throws Exception
String sentence;
String host = "localhost";
int SERVER_LISTEN_PORT = 5432;
BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
Socket clientSocket = null;
DataOutputStream outToServer = null;
BufferedInputStream inFromServer = null;
try
clientSocket = new Socket(host, SERVER_LISTEN_PORT);
outToServer = new DataOutputStream(clientSocket.getOutputStream());
inFromServer = new BufferedInputStream(clientSocket.getInputStream());
}catch(UnknownHostException e)
System.err.println("Don't know about host: "+host);
}catch(IOException e)
System.err.println("Couldn't get I/O for the connection to: "+host);
sentence = inFromUser.readLine();
outToServer.writeBytes(sentence + '\n');
FileOutputStream fos = new FileOutputStream("c://test.doc");
int totalDataRead;
int totalSizeWritten = 0;
int DATA_SIZE = 20480;
byte[] inData = new byte[DATA_SIZE];
System.out.println("Begin");
while ((totalDataRead = inFromServer.read(inData, 0, inData.length)) >= 0)
fos.write(inData, 0, totalDataRead);
totalSizeWritten = totalSizeWritten + totalDataRead;
System.out.println(totalSizeWritten);
System.out.println("Done");
fos.close();
clientSocket.close();
//For Client side
import java.io.*;
import java.net.*;
class Server
public static void main(String args[]) throws Exception
int SERVER_LISTEN_PORT = 5432;
String clientSentence;
ServerSocket welcomeSocket = null;
try
welcomeSocket = new ServerSocket(SERVER_LISTEN_PORT);
}catch(IOException ioe)
System.out.println("Could not listen on port: " + SERVER_LISTEN_PORT);
System.exit(1);
while(true)
Socket connectionSocket = null;
try
connectionSocket = welcomeSocket.accept();
}catch(IOException ioe)
System.err.println("Accept failed.");
System.exit(1);
BufferedReader inFromClient = new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
BufferedOutputStream outToClient = new BufferedOutputStream(connectionSocket.getOutputStream());
System.out.println(inFromClient.readLine());
int data;
int totalSizeTransferred = 0;
int totalSizeRead;
int PACKET_SIZE = 20480;
byte[] packet = new byte[PACKET_SIZE];
System.out.println("reading file...");
FileInputStream fis = new FileInputStream("c://JVM_Profiling_Report.doc");
while ((totalSizeRead = fis.read(packet, 0, packet.length)) >= 0)
outToClient.write(packet, 0, totalSizeRead);
totalSizeTransferred = totalSizeTransferred + totalSizeRead;
System.out.println(totalSizeTransferred);
System.out.println("done reading file...");
outToClient.close();
fis.close();
My question, any good idea for creating progress bar?
Thanks.