All works so far

src/GUI/ApplicationMain.java

@@ -36,6 +36,7 @@ public class ApplicationMain extends JPanel {
         content.add(paintGUI.getGlobal(), BorderLayout.WEST);
         content.add(chatScreen.panel2, BorderLayout.EAST);
         SwingUtilities.getRootPane(chatScreen.getSendButton()).setDefaultButton(chatScreen.getSendButton());
+
         frame.addWindowListener(new WindowAdapter()
         {
             @Override

src/GUI/DrawingArea.java

@@ -16,9 +16,10 @@ import java.awt.geom.RectangularShape;
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.IOException;
+import java.io.Serializable;
 import java.rmi.RemoteException;
 
-public class DrawingArea extends JPanel implements MouseMotionListener, MouseListener {
+public class DrawingArea extends JPanel implements MouseMotionListener, MouseListener, Serializable {
 
 
 
@@ -42,12 +43,14 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
     private Color shapeColor;// = new Color(0, 0, 0);
 
     private Mode currentMode;// = Mode.FREEHAND;
+
     /// Create a empty canvas ///
+
     private BufferedImage image;// = new BufferedImage(AREA_WIDTH, AREA_HEIGHT, BufferedImage.TYPE_INT_ARGB);
 
     /// Drawing tool
-    private Graphics2D g2;// = (Graphics2D) image.getGraphics();
 
+    private Graphics2D g2;// = (Graphics2D) image.getGraphics();
 
     public DrawingArea(Client client) {
         this.client = client;
@@ -64,7 +67,6 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
         addMouseMotionListener(this);
     }
 
-
     public Shape getDrawing() {
         return drawing;
     }
@@ -73,6 +75,16 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
         this.drawing = drawing;
     }
 
+    public Graphics2D getG2() { return g2; }
+
+
+    public void setG2(Graphics2D g2) { this.g2 = g2; }
+
+
+    public BufferedImage getImage() { return image; }
+
+    public void setImage(BufferedImage image) { this.image = image; }
+
 
     @Override
     public Dimension getPreferredSize()
@@ -108,12 +120,7 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
             Color borderColor = currentMode != Mode.ERASE ? shapeColor : Color.WHITE;
             g2.setColor(borderColor);
             g2.draw(drawing);
-            IDrawingController drawingController = client.getDrawingController();
-            try {
-                drawingController.broadcastDrawing(client.getUserName(), drawing);
-            } catch (RemoteException ex) {
-                ex.printStackTrace();
-            }
+
         }
     }
 
@@ -269,6 +276,7 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
 
     @Override
     public void mouseReleased(MouseEvent e) {
+        IDrawingController drawingController = client.getDrawingController();
         switch (currentMode) {
             case OVAL:
             case RECTANGLE:
@@ -295,6 +303,12 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
         /// This repaint is needed if we want to fill the drawing shape with color
         repaint();
 
+        try {
+            drawingController.broadcastDrawing(client.getUserName(), drawing, currentMode.toString(), shapeColor);
+        } catch (RemoteException ex) {
+            ex.printStackTrace();
+        }
+
         drawing = null;
     }
 
@@ -310,8 +324,9 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
 
     @Override
     public void mouseDragged(MouseEvent e) {
-        currentPoint = e.getPoint();
+        IDrawingController drawingController = client.getDrawingController();
 
+        currentPoint = e.getPoint();
         int x = Math.min(startPoint.x, e.getX());
         int y = Math.min(startPoint.y, e.getY());
         int width = Math.abs(startPoint.x - e.getX());
@@ -365,6 +380,11 @@ public class DrawingArea extends JPanel implements MouseMotionListener, MouseLis
         }
 
         repaint();
+        try {
+            drawingController.broadcastDraggingDrawing(client.getUserName(), drawing, currentMode.toString(), shapeColor);
+        } catch (RemoteException ex) {
+            ex.printStackTrace();
+        }
     }
 
     @Override

src/GUI/PaintGUI.java

@@ -217,16 +217,16 @@ public class PaintGUI extends JPanel {
 
 
 
-    public void showGUI() {
-        frame = new JFrame("Shared Whiteboard System");
-        JFrame.setDefaultLookAndFeelDecorated(true);
-        frame.setContentPane(global);
-
-        frame.setSize(800, 600);
-        frame.setLocationRelativeTo( null );
-        frame.setResizable(false);
-        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
-        frame.setVisible(true);
-    }
+//    public void showGUI() {
+//        frame = new JFrame("Shared Whiteboard System");
+//        JFrame.setDefaultLookAndFeelDecorated(true);
+//        frame.setContentPane(global);
+//
+//        frame.setSize(800, 600);
+//        frame.setLocationRelativeTo( null );
+//        frame.setResizable(false);
+//        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+//        frame.setVisible(true);
+//    }
 
 }
\ No newline at end of file

src/client/Client.java

@@ -85,8 +85,7 @@ public class Client
         {
             Client client = new Client(args[0]);
             client.connect();
-//            client.getChatScreen().showGUI();
-//            client.getPaintGUI().showGUI();
+//            client.getApplicationMain().getPaintGUI().getDrawingArea().setImage(client.drawingController.getCurrentImage());
             client.getApplicationMain().createAndShowGUI();
         }
         catch (Exception e)

src/client/DrawingUpdate.java

@@ -4,6 +4,10 @@ import GUI.DrawingArea;
 import remote.IDrawingUpdate;
 
 import java.awt.*;
+import java.awt.geom.Ellipse2D;
+import java.awt.geom.Line2D;
+import java.awt.geom.Rectangle2D;
+import java.awt.geom.RectangularShape;
 import java.io.Serializable;
 import java.rmi.RemoteException;
 import java.rmi.server.UnicastRemoteObject;
@@ -18,12 +22,45 @@ public class DrawingUpdate extends UnicastRemoteObject implements IDrawingUpdate
     }
 
     @Override
-    public boolean notifyDrawing(String fromClient, Shape drawing) throws RemoteException {
-        client.getApplicationMain().getPaintGUI().getDrawingArea().setDrawing(drawing);
+    public boolean notifyDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException {
+        Graphics2D g2 = client.getApplicationMain().getPaintGUI().getDrawingArea().getG2();
+        switch (mode) {
+            case "OVAL":
+            case "RECTANGLE":
+            case "CIRCLE":
+            case "FREEHAND":
+            case "LINE":
+                g2.setColor(color);
+                g2.draw(drawing);
+                break;
+            default:
+                System.out.println("Erased");
+        }
+        g2 = (Graphics2D) client.getApplicationMain().getPaintGUI().getDrawingArea().getImage().getGraphics();
+        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
+        g2.setColor(color);
+        client.getApplicationMain().getPaintGUI().getDrawingArea().repaint();
+        return true;
+    }
+
+    public boolean notifyDraggingDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException {
+        Graphics2D g2 = client.getApplicationMain().getPaintGUI().getDrawingArea().getG2();
+        switch (mode) {
+            case "FREEHAND":
+                g2.setColor(color);
+                g2.draw(drawing);
+                break;
+
+            case "ERASE":
+                g2.setColor(Color.WHITE);
+                g2.fill(drawing);
+                g2.draw(drawing);
+                break;
+
+            default:
+                break;
+        }
         client.getApplicationMain().getPaintGUI().getDrawingArea().repaint();
-//        DrawingArea drawingArea = (DrawingArea) client.getChatScreen().getDrawingPanel().getComponent(1);
-//        drawingArea.setDrawing(drawing);
-//        drawingArea.repaint();
-        return false;
+        return true;
     }
 }

src/remote/IDrawingController.java

 package remote;
 
 import java.awt.*;
+import java.awt.image.BufferedImage;
 import java.rmi.Remote;
 import java.rmi.RemoteException;
 
@@ -15,7 +16,8 @@ import java.rmi.RemoteException;
  */
 public interface IDrawingController extends Remote {
 
-    boolean broadcastDrawing(String fromClient, Shape drawing) throws RemoteException;
-
+    boolean broadcastDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException;
+    boolean broadcastDraggingDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException;
+//    BufferedImage getCurrentImage() throws RemoteException;
 
 }

src/remote/IDrawingUpdate.java

@@ -6,5 +6,6 @@ import java.rmi.Remote;
 import java.rmi.RemoteException;
 
 public interface IDrawingUpdate extends Remote, Serializable {
-    boolean notifyDrawing(String fromClient, Shape drawing) throws RemoteException;
+    boolean notifyDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException;
+    boolean notifyDraggingDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException;
 }

src/server/ChatController.java

@@ -6,14 +6,17 @@ import remote.IChatUpdate;
 import java.io.Serializable;
 import java.rmi.RemoteException;
 import java.rmi.server.UnicastRemoteObject;
+import java.util.ArrayList;
 
 public class ChatController extends UnicastRemoteObject implements IChatController, Serializable
 {
     private Server server;
+    private ArrayList<String> messages;
 
     public ChatController(Server server) throws RemoteException
     {
         this.server = server;
+        this.messages = new ArrayList<>();
     }
 
     @Override

src/server/DrawingController.java

@@ -3,32 +3,108 @@ package server;
 import remote.IDrawingController;
 import remote.IDrawingUpdate;
 
+import javax.imageio.ImageIO;
 import java.awt.*;
+import java.awt.image.BufferedImage;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.lang.reflect.Array;
 import java.rmi.RemoteException;
 import java.rmi.server.UnicastRemoteObject;
+import java.util.ArrayList;
 
 public class DrawingController extends UnicastRemoteObject implements IDrawingController {
 
+    private final static int AREA_WIDTH = 600;
+    private final static int AREA_HEIGHT = 620;
+
     private Server server;
+    private BufferedImage bufferedImage;
+//    private ImageCanvas image;
+    private Graphics2D g2;
 
     protected DrawingController(Server server) throws RemoteException {
         this.server = server;
+        this.bufferedImage = new BufferedImage(AREA_WIDTH, AREA_HEIGHT, BufferedImage.TYPE_INT_ARGB);
+        g2 = (Graphics2D) bufferedImage.getGraphics();
+        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
     }
 
     @Override
-    public boolean broadcastDrawing(String fromClient, Shape drawing) throws RemoteException {
+    public boolean broadcastDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException {
         System.out.print("Broadcasting drawing to everyone...");
 
+        // 1. Draw on server
+        g2.setColor(color);
+        g2.draw(drawing);
+        g2 = (Graphics2D) bufferedImage.getGraphics();
+        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
+        g2.setColor(color);
+        g2.drawImage(bufferedImage, 0,0, null);
+
+        // 2. Broadcast to other clients
         IDrawingUpdate client;
 
         for( User u : server.users )
         {
+            if (!u.getUserName().equals(fromClient)) {
                 client = u.getIDrawingUpdate();
-            client.notifyDrawing(fromClient, drawing);
+                client.notifyDrawing(fromClient, drawing, mode, color);
+            }
         }
 
         System.out.print("...DONE\n");
 
         return true;
     }
+
+    public boolean broadcastDraggingDrawing(String fromClient, Shape drawing, String mode, Color color) throws RemoteException {
+        System.out.print("Broadcasting dragging drawing to everyone...");
+
+        // 1. Draw on server
+//        g2.setColor(color);
+//        g2.draw(drawing);
+
+        // 2. Broadcast to other clients
+        IDrawingUpdate client;
+
+        for( User u : server.users )
+        {
+            if (!u.getUserName().equals(fromClient)) {
+                client = u.getIDrawingUpdate();
+                client.notifyDraggingDrawing(fromClient, drawing, mode, color);
+            }
+        }
+
+        System.out.print("...DONE\n");
+
+        return true;
+    }
+
+//    public ImageCanvas getCurrentImage() {
+//        return image;
+//    }
+}
+
+class ImageCanvas implements Serializable {
+    transient ArrayList<BufferedImage> images;
+
+    private void writeObject(ObjectOutputStream out) throws IOException {
+        out.defaultWriteObject();
+        out.writeInt(images.size()); // how many images are serialized?
+        for (BufferedImage eachImage : images) {
+            ImageIO.write(eachImage, "png", out); // png is lossless
+        }
+    }
+
+    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
+        in.defaultReadObject();
+        final int imageCount = in.readInt();
+        images = new ArrayList<BufferedImage>(imageCount);
+        for (int i=0; i<imageCount; i++) {
+            images.add(ImageIO.read(in));
+        }
+    }
 }
\ No newline at end of file