when i run the server and the client i get the following errors:
Client:

Exception in thread "main" java.io.EOFException
        at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2570)
        at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1314)
        at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
        at Client.main(Client.java:29)
Java Result: 1

not really a error but it should receive the patients name?:

waiting for connection...
Message Recieved:null
waiting for connection...

so heres my code:
Server.java

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.logging.Level;
import java.util.logging.Logger;


public class Server extends Thread {

    private ServerSocket server = null;
    private int port = 1234;

    public static void main(String[] args) {
        Server server = new Server();
        server.start();
    }

    public Server() {
        try {
            server = new ServerSocket(port);
        } catch (IOException ex) {
        }
    }

    public void run() {

        while (true) {
            try {
                listenForConnections();
            } catch (IOException ex) {
            }
        }
    }

    private void listenForConnections() throws IOException {
        System.out.println("waiting for connection...");
        Socket socket = server.accept();
        returnPatient(socket);

    }

    private void returnPatient(Socket socket) throws IOException {
        ObjectOutputStream out = null;
        ObjectInputStream in = null;
        try {

            in = new ObjectInputStream(socket.getInputStream());
            Patient patient = (Patient) in.readObject();
            System.out.println("Message Recieved:" + patient.getName());

            out = new ObjectOutputStream(socket.getOutputStream());
            Patient patient1 = new Patient();
            patient1.setID(1);
            patient1.setName("John");

            Patient patient2 = new Patient();
            patient2.setID(2);
            patient2.setName("Luke");

            if ("John".equalsIgnoreCase(patient.getName())) {
            out.writeObject(patient1);
            } else if ("Luke".equalsIgnoreCase(patient.getName())) {
            out.writeObject(patient2);
            }

        } catch (IOException ex) {
            Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
        } catch (ClassNotFoundException ex) {
            Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
        } finally{
            in.close();
            out.close();
            socket.close();
        }
    }
}

Patient.java

import java.io.Serializable;

public class Patient implements Serializable {

    int ID;
    String name;

    public int getID() {
        return this.ID;
    }

    void setID(int ID) {
        ID = this.ID;
    }

    public String getName() {
        return this.name;
    }

    void setName(String string) {
        string = this.name;
    }
}

Client.java

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.util.logging.Level;
import java.util.logging.Logger;


public class Client {

    public static void main(String[] args) throws IOException {
        ObjectOutputStream oos = null;
        ObjectInputStream ois = null;
        try {
            Socket socket = new Socket("localhost", 1234);
            
            Patient patient = new Patient();
            patient.setName("Luke");            
            oos = new ObjectOutputStream(socket.getOutputStream());
            oos.writeObject(patient);
            
            ois = new ObjectInputStream(socket.getInputStream());
            Patient result = (Patient) ois.readObject();
            
            System.out.println("ID= " + result.getID() + "\nName= " + result.getName());

        } catch (ClassNotFoundException ex) {
            Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            ois.close();
            oos.close();
        }

    }
}

i have the patient.java both client and server side and there both exactly the same.

thanks in advance

In patient.java...

void setName(String string) {
        string = this.name;
    }

Are you sure you don't have that backwards? That would explain why you're getting a null name. Your setID does the same thing.

thanks IsharaComix something so simple :P i couldent see it haha thanks again

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