frist

.idea/encodings.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding" addBOMForNewFiles="with NO BOM" />
+</project>
\ No newline at end of file

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="11" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file

.idea/modules.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/lab11.iml" filepath="$PROJECT_DIR$/lab11.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

lab11.iml

+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file

src/ChatArea.java

+import javax.swing.*;
+
+public class ChatArea extends JTextArea {
+    private static final int ROWS = 10, COLUMNS = 30;
+
+    public ChatArea() {
+
+        super(ROWS, COLUMNS);
+        this.setEditable(false);
+        this.setVisible(true);
+    }
+
+    public void addMessage(String username, String message)
+    {
+        this.setText(this.getText() + username + ":\n" + message + "\n");
+    }
+}

src/ChatRoomGUI.java

+import javax.swing.*;
+import java.awt.*;
+
+public class ChatRoomGUI extends JFrame implements NewMessageListener{
+    private final String WINDOWS_TITLE = "AUT Chat Room";
+    private final int WIDTH = 500, HEIGHT = 500;
+    private final int X = 100, Y = 100;
+    ChatArea chatArea;
+    MessageArea messageArea;
+    ParticipantsArea participantsArea;
+    String username;
+
+    public ChatRoomGUI() {
+        super();
+        this.setLayout(new BorderLayout());
+        this.setTitle(WINDOWS_TITLE);
+        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        this.setSize(WIDTH, HEIGHT);
+        this.setLocation(X, Y);
+        chatArea = new ChatArea();
+        this.add(new JScrollPane(chatArea), BorderLayout.CENTER);
+        messageArea = new MessageArea(this);
+        this.add(messageArea, BorderLayout.PAGE_END);
+        participantsArea = new ParticipantsArea();
+        this.add(new JScrollPane(participantsArea), BorderLayout.WEST);
+        this.setVisible(true);
+    }
+
+    public void addNewMessage(String name, String message)
+    {
+        this.chatArea.addMessage(name, message);
+    }
+
+    public void addNewParticipant(String name)
+    {
+        this.participantsArea.addNewParticipant(name);
+    }
+
+    public void removeNewParticipant(String name)
+    {
+        this.participantsArea.removeParticipant(name);
+    }
+
+    public void addNewMessageListener(String name, String message)
+    {
+        this.chatArea.addMessage(name, message);
+    }
+
+    public void addNewParticipantListener(String name) {this.participantsArea.addNewParticipant(name);}
+}

src/Main.java

+public class Main {
+        public static void main(String[] args) {
+            ChatRoomGUI chatRoomGUI = new ChatRoomGUI();
+            NameFrame nameFrame = new NameFrame(chatRoomGUI);
+            chatRoomGUI.addNewParticipant(nameFrame.username);
+            chatRoomGUI.removeNewParticipant(nameFrame.username);
+        }
+    }
+

src/MessageArea.java

+import network.Network;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.io.IOException;
+
+public class MessageArea extends JPanel{
+    JTextField textField;
+    JButton btn;
+
+    public MessageArea(ChatRoomGUI chatRoomGUI) throws HeadlessException {
+        super();
+        this.setLayout(new BorderLayout());
+        textField = new JTextField();
+        textField.setEditable(true);
+        add(textField, BorderLayout.CENTER);
+        btn = new JButton("SEND");
+        add(btn, BorderLayout.EAST);
+        btn.addActionListener(new ActionListener() {
+            @Override
+            public void actionPerformed(ActionEvent e) {
+                chatRoomGUI.addNewMessage(chatRoomGUI.username, textField.getText());
+                try {
+                    Network n = new Network("localhost", 1234, textField.getText());
+                } catch (IOException e1) {
+                    e1.printStackTrace();
+                }
+            }
+        });
+        setVisible(true);
+    }
+}

src/NameFrame.java

+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+
+public class NameFrame extends JFrame {
+    private static final String BTN_TXT = " Start Chatting ...";
+    private static final String LABEL_TXT = " Choose Your UserName  ";
+    private static final int WIDTH = 300, HEIGHT = 100;
+    JTextField textField;
+    JButton btn;
+    String username;
+
+    public NameFrame(ChatRoomGUI chatRoomGUI) throws HeadlessException {
+        super();
+        this.setLayout(new BorderLayout());
+        JLabel label = new JLabel("Choose Your UserName");
+        add(label, BorderLayout.PAGE_START);
+        textField = new JTextField();
+        add(textField, BorderLayout.CENTER);
+        btn = new JButton(BTN_TXT);
+        add(btn, BorderLayout.PAGE_END);
+        btn.addActionListener(new ActionListener() {
+            @Override
+            public void actionPerformed(ActionEvent e) {
+                doClickAction();
+                chatRoomGUI.addNewParticipant(username);
+                chatRoomGUI.username = username;
+            }
+        });
+        setSize(WIDTH, HEIGHT);
+        setVisible(true);
+    }
+
+    public void doClickAction()
+    {
+        setVisible(false);
+        username = textField.getText();
+    }
+}

src/NewMessageListener.java

+public interface NewMessageListener {
+    void addNewMessageListener(String name, String message);
+    void addNewParticipantListener(String name);
+}

src/ParticipantsArea.java

+import javax.swing.*;
+import java.awt.*;
+
+public class ParticipantsArea extends JPanel {
+    private final int ROW = 20, COLUMN = 1;
+    DefaultListModel<String> model;
+    JList<String> list;
+
+    public ParticipantsArea() throws HeadlessException {
+        super();
+        GridLayout g = new GridLayout(20, 1);
+        this.setLayout(g);
+        JLabel label = new JLabel("Online Users");
+        this.add(label);
+        this.model= new DefaultListModel();
+        this.list = new JList(model);
+        this.add(list);
+        this.setVisible(true);
+    }
+
+    public void addNewParticipant(String name)
+    {
+        if (!this.model.contains(name)) {
+            this.model.addElement(name);
+        }
+    }
+
+    public void removeParticipant(String name)
+    {
+        if (this.model.contains(name)) {
+            this.model.removeElement(name);
+        }
+    }
+}

src/network/Network.java

+package network;
+
+import java.net.*;
+import java.io.*;
+
+public class Network {
+
+    private String serverName;
+    private int port;
+    Socket client;
+
+    public Network(String serverName, int port, String message) throws IOException {
+        try {
+            System.out.println("Connecting to " + serverName + " on port " + port);
+            client = new Socket(serverName, port);
+            System.out.println("Just connected to " + client.getRemoteSocketAddress());
+            OutputStream outToServer = client.getOutputStream();
+            DataOutputStream out = new DataOutputStream(outToServer);
+
+            out.writeUTF(message);
+            InputStream inFromServer = client.getInputStream();
+
+            DataInputStream in = new DataInputStream(inFromServer);
+            System.out.println("Server says " + in.readUTF());
+            client.close();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        this.serverName = serverName;
+        this.port = port;
+    }
+
+}