Sever.java file
import java.net.*;
import java.io.*;
import java.util.*;
/**
* Simple server use to teach University of
* Northumbria's Operating Systems and Networks modules.
* To be used with compatible simple client.
* <PRE>
* Protocol:
* client <---message--- server
* message = <message body> CRLF
* </PRE>
*
* @author Adrian P Robson & Frank Hindle
* @version Server 1.2, 16 January 2010
*/
public class Server {
// private static String message1 = "Hello, from Alex. You are client number ";
private static String message1 = "The Candidates List is ";
private static class ServeClient extends Thread {
private Socket sock;
private String data;
public ServeClient( Socket s, String data ) {
sock = s;
data= "";
}
public void run() {
System.out.println("** Server thread started");
try {
OutputStream outToClient = sock.getOutputStream();
String messageOut = new String(message1 + data+ "\r\n");
// CR+LF added at end of message to enable reading from remote socket using readLine
outToClient.write(messageOut.getBytes());
System.out.println("** Message sent");
}
catch (IOException x ) {
System.out.println("** Problem serving client: " + x );
}
System.out.println("** Server thread finished");
}
}
private static int getPortNumber()
{ /**
* input port number from keyboard and validate it
**/
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
try {
int p = 0;
boolean incorrect;
do {
System.out.print("Enter port number: ");
try {
p = Integer.parseInt(in.readLine());
if ((p < 1024) || (p > 65535)) {
System.out.println("Port number out of range");
incorrect=true;
} else {
incorrect=false;
}
}
catch ( NumberFormatException x ) {
System.out.println("Port should be integer");
incorrect = true;
}
} while ( incorrect );
return p;
}
catch (IOException x ) {
throw new Error("unexpected exception -> " + x);
}
}
public static void main( String[] args ) throws Exception
{
// int clientNum =0;
int port = getPortNumber();
Scanner CD = new Scanner(new FileReader("Candidates.txt"));
try {
ServerSocket welcomeSocket = new ServerSocket(port); // creates server socket with port number bound to the socket
System.out.println("ServerSocket created");
while (CD.hasNext()) {
String line = CD.nextLine();
System.out.println("Ready to acccept connections");
Socket connectedSocket = welcomeSocket.accept(); // execution will wait here until a connection request is received
//clientNum++;
System.out.println("Connection accepted from " + connectedSocket.getInetAddress().getHostAddress());
//System.out.println("Now starting server thread for client " + clientNum);
// Thread t = new ServeClient(connectedSocket, clientNum);
System.out.println("Now starting server thread for client " + line);
Thread t = new ServeClient(connectedSocket, line);
t.start();
}
}
catch (IOException x ) {
System.out.println("Sockets problem: " + x );
}
}
}Client.java
import java.net.*;
import java.io.*;
/**
* Simple client used to teach University of
* Northumbria's Operating Systems and Networks modules.
* To be used with compatible simple server.
* <PRE>
* Protocol:
* client <---message--- server
* message = <message body> CRLF
* </PRE>
* @author Adrian P Robson & Frank Hindle
* @version Client 1.1, 16 January 2010
*/
public class Client {
private static InetSocketAddress getHostAndPort()
{ //inputs, from the keyboard, host and port number for the server
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
try {
System.out.print("Enter name or IP adddress of server: ");
String h = in.readLine();
int p = 0;
boolean incorrect;
InetSocketAddress addr = null;
do {
System.out.print("Enter portnumber: ");
try {
p = Integer.parseInt(in.readLine());
try {
addr = new InetSocketAddress(h,p);
incorrect = false;
}
catch ( IllegalArgumentException x ) {
System.out.println("Port out of range");
incorrect = true;
}
}
catch ( NumberFormatException x ) {
System.out.println("Port should be integer");
incorrect = true;
}
} while ( incorrect );
return addr;
}
catch (IOException x ) {
throw new Error("unexpected exception -> " + x);
}
} // end of getHostAndPort
public static void main(String[] args)
{
Socket socket = new Socket();
String message = null;
String remoteHost = null;
System.out.println("Client program starting:");
// get and check the server address
InetSocketAddress addr = getHostAndPort();
if ( addr.isUnresolved() ) {
System.out.print("Socket address unresolved - ");
System.out.println("bad host = " + addr.getHostName() );
System.exit(1);
}
System.out.print("Socket address resolved as ");
System.out.println(addr.getHostName() +
"/" + addr.getPort());
// now connect to the server
try {
System.out.println("Attempting to connect to server");
socket.connect(addr);
remoteHost= socket.getInetAddress().getHostName();
System.out.println("Connection made to " + remoteHost );
}
catch (Exception x) {
System.out.println("Unable to connect to server - " + x);
System.exit(1);
}
// now read a message from the server
try {
//message from server is a single line ending with CRLF so use a Buffered reader's readline method
BufferedReader inFromServer = new BufferedReader(new InputStreamReader(socket.getInputStream() ));
message= inFromServer.readLine();
/*************** Alternative, non-buffered read from socket:
* byte [] buff = new byte[4000]; // buffer for messages read from the socket
* InputStream inFromServer = socket.getInputStream();
* // now read from the socket
* int len = inFromServer.read(buff);
* // convert contents of buffer to a string
* message = new String(buff, 0, len-2); // assume CRLF was at end of message, so remove these two characters
**********/
System.out.println();
System.out.println("Message from server is >" + message + "<");
System.out.println();
}
catch (IOException x ) {
System.out.println("Problem encountered -> " + x );
}
System.out.println("Simple sockets client finished");
System.out.println();
} // end of main
}Candidates.txt
ID Fname LName
12 Alex Yui
24 Andy Lui
Can somebody help me , when i run it take nothings