Java project

package com.company; import javax.swing.*; import java.io.*; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.net.ServerSocket; import java.net.Socket; /** * * @author maxime */ public class server_GUI extends JFrame implements ActionListener { JPanel serverPanel = new JPanel(); JLabel label1 = new JLabel("Server Connection"); JLabel label2 = new JLabel(" "); JLabel label3 = new JLabel(" "); JLabel label4 = new JLabel(" "); JLabel label5 = new JLabel("fowl ");// display client message.. JLabel label6 = new JLabel(" "); JLabel label7 = new JLabel("Port Number:"); JTextField text1 = new JTextField(" "); JButton button1 = new JButton("START"); JButton button2 = new JButton("CONNECT "); server_GUI() { button1.addActionListener(this); button2.addActionListener(this); serverPanel.setLayout(new GridLayout(6, 3)); serverPanel.add(label4); serverPanel.add(label3); serverPanel.add(label5); serverPanel.add(label6); serverPanel.add(label1); serverPanel.add(label2); serverPanel.add(label7); serverPanel.add(text1); serverPanel.add(button1); serverPanel.add(button2); //Add to Frame this.setDefaultCloseOperation(DISPOSE_ON_CLOSE); this.getContentPane().add(serverPanel); this.setPreferredSize(new Dimension(600, 600)); this.setVisible(true); this.pack(); } int portnumber; connection con = new connection(); @Override public void actionPerformed(ActionEvent f) { if (f.getSource().equals(button1)) { label2.setText("Initiating Server..."); String input = text1.getText().trim(); System.out.println(input); System.out.println("Initiating Server..."); } else if (f.getSource().equals(button2)) { String input = text1.getText().trim(); //label2.setBackground(Color.red); System.out.println(input); portnumber = Integer.parseInt(input); // TO DO //have a label to get text from client con.start(); label2.setText("Creating a server socket that listens on port " + portnumber); label4.setText("Your server is up and running!"); // label5.setText("Client's message: " + textFromClient); label4.setBackground(Color.BLUE); System.out.println("Creating a server socket that listens on port " + portnumber); } //throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates. } class connection extends Thread { public void run() { try { System.out.println("Your server is up and running!"); ServerSocket serverSocket = new ServerSocket(portnumber); //System.out.println("Creating a server socket that listens on port " + portnum); // This section of the code allows the server to listen infinitely for the client to connect while (true) { Socket clientSocketConnection = serverSocket.accept(); try (PrintWriter out = new PrintWriter(clientSocketConnection.getOutputStream(), true)) { BufferedReader in = new BufferedReader(new InputStreamReader(clientSocketConnection.getInputStream())); //Send message to a client System.out.println("You are connected to the server!"); //receive message from client String textFromClient = in.readLine(); System.out.println("Client's message: " + textFromClient); //send a message to the client out.println("You told me: " + textFromClient); out.println("See you soon! "); } } } catch (Exception e) { System.out.println("Exception caught: " + e); } } } }