diff --git a/src/main/java/ChatGUI.java b/src/main/java/ChatGUI.java
new file mode 100644
index 0000000..743e4f4
--- /dev/null
+++ b/src/main/java/ChatGUI.java
@@ -0,0 +1,144 @@
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.Font;
+import java.awt.Toolkit;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JMenu;
+import javax.swing.JMenuBar;
+import javax.swing.JMenuItem;
+import javax.swing.JPanel;
+import javax.swing.JScrollPane;
+import javax.swing.JTextArea;
+import javax.swing.JTextField;
+
+public class ChatGUI implements ActionListener {
+
+	// Menu items for font sizes
+	JMenuItem small = new JMenuItem("small-font");
+	JMenuItem medium = new JMenuItem("medium-font");
+	JMenuItem large = new JMenuItem("large-font");
+
+	// Menu items for font colors
+	JMenuItem black = new JMenuItem("black");
+	JMenuItem red = new JMenuItem("red");
+	JMenuItem blue = new JMenuItem("blue");
+	JMenuItem green = new JMenuItem("green");
+
+	JMenuItem exit = new JMenuItem("Exit");
+
+	JTextField inputTextField = new JTextField();
+	JTextArea outputTextArea = new JTextArea();
+	JButton sendButton = new JButton("Senden");
+
+	JFrame gui;
+
+	public ChatGUI() {
+		gui = new JFrame();
+
+		// Set up the main frame
+		gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+		gui.setTitle("java-chat");
+		gui.setLayout(new BorderLayout());
+
+		// Set up the menu bar
+		JMenuBar bar = new JMenuBar();
+		gui.setJMenuBar(bar);
+
+		// Create menu items and menus
+		JMenu options = new JMenu("options");
+		JMenu colors = new JMenu("font-colors");
+		JMenu size = new JMenu("font-size");
+
+		JMenu menu = new JMenu("File");
+		menu.add(exit);
+		menu.add(options);
+		bar.add(menu);
+		options.add(colors);
+		options.add(size);
+
+		colors.add(black);
+		colors.add(red);
+		colors.add(blue);
+		colors.add(green);
+
+		size.add(small);
+		size.add(medium);
+		size.add(large);
+
+		// Register action listeners for menu items
+		red.addActionListener(this);
+		blue.addActionListener(this);
+		black.addActionListener(this);
+		green.addActionListener(this);
+		small.addActionListener(this);
+		medium.addActionListener(this);
+		large.addActionListener(this);
+
+		exit.addActionListener(this);
+
+		bar.add(menu);
+
+		// Set up the output text area with scrolling
+		JScrollPane outputScrollPane = new JScrollPane(outputTextArea);
+		gui.add(outputScrollPane, BorderLayout.CENTER);
+		
+		// Set up the input panel with text field and send button
+		JPanel inputPanel = new JPanel(new BorderLayout());
+		inputPanel.add(inputTextField, BorderLayout.CENTER);
+		inputPanel.add(sendButton, BorderLayout.EAST);
+		gui.add(inputPanel, BorderLayout.SOUTH);
+
+		inputTextField.addActionListener(this);
+		sendButton.addActionListener(this);
+
+		// Set the size of the GUI to be a quarter of the screen size
+		Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
+		int quarterWidth = screenSize.width / 2;
+		int quarterHeight = screenSize.height / 2;
+		gui.setSize(quarterWidth, quarterHeight);
+		gui.setVisible(true);
+	}
+
+	// main methode zum Testen, müsste bei Implementation entfernt werden
+	public static void main(String[] args) {
+
+		new ChatGUI();
+	}
+
+	@Override
+	public void actionPerformed(ActionEvent e) {
+		if (e.getSource() == exit) {
+			System.exit(0);
+		}
+		if (e.getSource() == inputTextField || e.getSource() == sendButton) {
+			String inputText = inputTextField.getText();
+			outputTextArea.append(inputText + "\n");
+			inputTextField.setText("");
+		}
+		if (e.getSource() == red) {
+			outputTextArea.setForeground(Color.RED);
+
+		} else if (e.getSource() == blue) {
+			outputTextArea.setForeground(Color.BLUE);
+		} else if (e.getSource() == black) {
+			outputTextArea.setForeground(Color.BLACK);
+		} else if (e.getSource() == green) {
+			outputTextArea.setForeground(Color.GREEN);
+		}
+		if (e.getSource() == small) {
+			outputTextArea.setFont(outputTextArea.getFont().deriveFont(Font.PLAIN, 12));
+		}
+		if (e.getSource() == medium) {
+			outputTextArea.setFont(outputTextArea.getFont().deriveFont(Font.PLAIN, 16));
+		}
+		if (e.getSource() == large) {
+			outputTextArea.setFont(outputTextArea.getFont().deriveFont(Font.PLAIN, 20));
+		}
+
+	}
+}
diff --git a/src/main/java/ClientHandler.java b/src/main/java/ClientHandler.java
index e4104da..b30e37a 100644
--- a/src/main/java/ClientHandler.java
+++ b/src/main/java/ClientHandler.java
@@ -9,6 +9,7 @@ public class ClientHandler implements Runnable {
   private String name; 
   private BufferedReader fromClientReader;
   private PrintWriter toClientWriter;
+  private String lastMessage;
   
   // Constructor for ClientHandler
   public ClientHandler(ChatServer chatServer, Socket connectionToClient) {
@@ -33,6 +34,7 @@ public class ClientHandler implements Runnable {
       while (message!=null) {
         // Broadcast the client's message to all connected clients
         chatServer.broadcastMessage(name + ": " + message);
+        lastMessage = message;
         message = fromClientReader.readLine();
       }   
     }
@@ -64,4 +66,8 @@ public class ClientHandler implements Runnable {
       toClientWriter.println(message); // Send the message to the client
       toClientWriter.flush(); // Flush the stream
     }
+    //Test method
+    public String getLastMessage() {
+    	return lastMessage;
+    }
 }
diff --git a/src/test/java/ChatGUITest.java b/src/test/java/ChatGUITest.java
new file mode 100644
index 0000000..47cc055
--- /dev/null
+++ b/src/test/java/ChatGUITest.java
@@ -0,0 +1,80 @@
+import static org.junit.Assert.assertEquals;
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.event.ActionEvent;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class ChatGUITest {
+
+    private ChatGUI chatGUI;
+
+    @Before
+    public void setUp() {
+        chatGUI = new ChatGUI();
+    }
+    @Test
+    public void testSetOutputTextColorRed() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.red));
+        assertEquals(Color.RED, chatGUI.outputTextArea.getForeground());
+    }
+    @Test
+    public void testSetOutputTextColorBlue() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.blue));
+        assertEquals(Color.BLUE, chatGUI.outputTextArea.getForeground());
+    }
+    @Test
+    public void testSetOutputTextColorBlack() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.black));
+        assertEquals(Color.BLACK, chatGUI.outputTextArea.getForeground());
+    }
+
+    @Test
+    public void testSetOutputTextColorGreen() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.green));
+        assertEquals(Color.GREEN, chatGUI.outputTextArea.getForeground());
+    }
+    @Test
+    public void testSetOutputTextFontSizeSmall() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.small));
+        Font expectedFont = chatGUI.outputTextArea.getFont().deriveFont(Font.PLAIN, 12);
+        assertEquals(expectedFont, chatGUI.outputTextArea.getFont());
+    }
+    @Test
+    public void testSetOutputTextFontSizeMedium() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.medium));
+        Font expectedFont = chatGUI.outputTextArea.getFont().deriveFont(Font.PLAIN, 16);
+        assertEquals(expectedFont, chatGUI.outputTextArea.getFont());
+    }
+    @Test
+    public void testSetOutputTextFontSizeLarge() {
+        chatGUI.actionPerformed(new TestActionEvent(chatGUI.large));
+        Font expectedFont = chatGUI.outputTextArea.getFont().deriveFont(Font.PLAIN, 20);
+        assertEquals(expectedFont, chatGUI.outputTextArea.getFont());
+    }
+    @Test
+    public void testSendButtonActionPerformed() {
+        chatGUI.inputTextField.setText("Testnachricht");
+        chatGUI.sendButton.doClick();
+
+        String expectedOutput = "Testnachricht\n";
+        assertEquals(expectedOutput, chatGUI.outputTextArea.getText());
+    }
+    @Test
+    public void testInputTextFieldActionPerformed() {
+
+        chatGUI.inputTextField.setText("Testnachricht");
+        chatGUI.actionPerformed(new ActionEvent(chatGUI.inputTextField, ActionEvent.ACTION_PERFORMED, ""));
+
+
+        String expectedOutput = "Testnachricht\n";
+        assertEquals(expectedOutput, chatGUI.outputTextArea.getText());
+
+
+        assertEquals("", chatGUI.inputTextField.getText());
+    }
+}
+
+
diff --git a/src/test/java/TestActionEvent.java b/src/test/java/TestActionEvent.java
new file mode 100644
index 0000000..1a60355
--- /dev/null
+++ b/src/test/java/TestActionEvent.java
@@ -0,0 +1,10 @@
+import java.awt.event.ActionEvent;
+
+public class TestActionEvent extends ActionEvent {
+
+    private static final long serialVersionUID = 1L;
+
+    public TestActionEvent(Object source) {
+        super(source, ActionEvent.ACTION_PERFORMED, "Test command");
+    }
+}
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