I'm trying to make a very simple chat program that can accommodate multiple clients. I have a multi-threaded server and can connect multiple clients to it, but the server only communicates with a single client (as it should, each client is on its own thread) I need help getting the server to send all messages from all connected clients to each client. I think I'd need to share a single object between threads? Here's the code:
server:
import java.net.ServerSocket;
import java.net.Socket;
public class ThreadedCommandServer {
public static void main(String[] args) throws Exception {
System.out.println("Starting server....");
int port = 8989;
ServerSocket ss = new ServerSocket(port);
while(true) {
System.out.println("Waiting for connection from client...");
Socket socket = ss.accept();
ServerThread st = new ServerThread(socket);
st.start();
}
}
}
server thread:
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.net.Socket;
public class ServerThread extends Thread {
private Socket socket = null;
private String s;
public ServerThread(Socket s) {
socket = s;
}
public void run() {
try {
InputStream is = socket.getInputStream();
ObjectInputStream ois = new ObjectInputStream(is);
s = (String) ois.readObject();
System.out.println("received string: " + s);
OutputStream os = socket.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(os);
oos.writeObject(s);
System.out.println("sent object back to client...");
} catch (Exception e) {
System.out.println(e.toString());
}
}
}
client:
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.Socket;
public class Controller {
private ClientFrame cf;
private String message;
private Socket socket;
private String response;
public Controller(ClientFrame cf) {
this.cf = cf;
}
public void sendChat(String s) {
message = s;
System.out.println("FROM CONTROLLER: received: " + message);
try {
InetAddress i = InetAddress.getByName("localhost");
socket= new Socket(i, 8989);
OutputStream os = socket.getOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(os);
System.out.println("FROM CONTROLLER: sending message to the server...");
oos.writeObject(message);
InputStream is = socket.getInputStream();
ObjectInputStream ois = new ObjectInputStream(is);
System.out.println("getting string back from server....");
response = (String) ois.readObject();
cf.updateGUI(response);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
GUI:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class ClientFrame extends JFrame {
private JTextArea chatArea;
private JTextField type;
private JButton submit;
private JPanel upper;
private JPanel lower;
private BorderLayout bl;
JScrollPane jsp;
Controller c;
public ClientFrame() {
bl = new BorderLayout();
upper = new JPanel();
lower = new JPanel();
chatArea = new JTextArea("chat goes here", 20, 30);
c = new Controller(this);
chatArea.setEditable(false);
chatArea.setLineWrap(true);
type = new JTextField("type here", 20);
jsp = new JScrollPane(chatArea);
new SmartScroller(jsp);
lower.add(type);
submit = new JButton("send");
submit.addActionListener(new Submit());
type.addActionListener(new Submit());
lower.add(submit);
upper.add(jsp);
this.setSize(400, 600);
this.setLayout(bl);
this.setTitle("MattChatt");
this.add(upper, BorderLayout.NORTH);
this.add(lower, BorderLayout.SOUTH);
this.setVisible(true);
this.setResizable(false);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public void updateGUI(String s) {
chatArea.append("\n" + s);
}
private class Submit implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
if (type.getText().equals("")) {
System.out.println("no text entered");
} else {
System.out.println("submitted");
c.sendChat(type.getText());
type.setText("");
}
}
}
}
