Why can't my image be displayed?

Question

Anybody could help me with the code? the image does not seem to appear when i run it...is it because JPanel cannot work with Canvas? or is it because of the error in getImage() method?
This are the code for the ImageClient
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
import java.util.Vector;
import javax.swing.*;
public class ImageClient extends JFrame implements ActionListener
     private JMenuBar mainMenu;
     private JMenuItem open, save, exit, scale;
     private JMenu fileMenu, editMenu;
     private JPanel mainPane;
     private JFileChooser imagesFile;
     private JLabel imageLabel, imgPanel;
     String fname;
     // Declare all the Input/Output object variables.
     Socket toHost = null;
     PrintWriter out = null;
    ObjectInputStream in = null;
     ObjectOutputStream objectOut = null;
     // Declare the user interface object variables.
     // images is a Vector used to store the image names as strings. This simply
     // stores the Vector of file names transmitted by the server.
     Vector images;
     // params is vector used to store the parameters such as image name and operation
     Vector params;
     // img is the image that will be displayed. This simply stores the Image
     // transmitted by the server.
     Image img = null;
     // canvas is a subclass of the awt abstract Canvas class. This is where the
     // Image will be displayed (see bottom of file for MyCanvas class definition).
     MyCanvas canvas = null;
     public ImageClient(String host, int port){
          initGUI();
          initSocket(host, port);
     protected void initGUI()
          Container cpane = getContentPane();
          canvas = new MyCanvas(null);
          //Open the menu in order to img from any folder
          imagesFile = new JFileChooser();
          imagesFile.addActionListener(this);
          //create an JPanel Container
          mainPane = new JPanel();
          mainPane.setBackground(Color.white);
          //create an intermedia panel to hold panel and button
          mainMenu = new JMenuBar();
          setJMenuBar(mainMenu);
          setContentPane(mainPane);
          fileMenu = new JMenu("File");
          mainMenu.add(fileMenu);
          editMenu = new JMenu("Features");
          mainMenu.add(editMenu);
          //JMenuItem(open, save, exit) to be added into the JMenu(fileMenu)
          open = new JMenuItem("Open...");
          save = new JMenuItem("Save...");
          exit = new JMenuItem("Exit...");
          scale = new JMenuItem("Scale");
          imgPanel = new JLabel();
          JPanel images = new JPanel(new BorderLayout());
          imageLabel = new JLabel();
          images.add(imageLabel);
          fileMenu.add(open);
          fileMenu.add(save);
          fileMenu.add(exit);
          editMenu.add(scale);
          //add events to the JMenuItem(open, save, exit)
          open.addActionListener(this);
          save.addActionListener(this);
          exit.addActionListener(this);
          scale.addActionListener(this);
          mainPane.add(imgPanel, BorderLayout.CENTER);
          imgPanel.add(canvas, BorderLayout.NORTH);
          //to set the close menu on the menubar
          setDefaultCloseOperation(DISPOSE_ON_CLOSE);
          //to set the size of the frame
          setSize(500,500);
          //to set the main pane visible to the user
          setVisible(true);
     protected void initSocket(String host, int port)
          try
                toHost = new Socket(host, port);                                        // 1                                   
                out = new PrintWriter(toHost.getOutputStream(), true);               // 2
                in = new ObjectInputStream(toHost.getInputStream());
                objectOut = new ObjectOutputStream(toHost.getOutputStream());   // 3
         catch (UnknownHostException e)
              System.err.println("Unknown host in initSocket()");
             catch (IOException e)
                 System.err.println("IO error in initSocket()");
     public void actionPerformed(ActionEvent e)
          if(e.getSource()==(open))
               imagesFile.showOpenDialog(this); //to have the OPEN dialog box
          if(e.getSource() == imagesFile)
               //to get the file from the exact folder that the user clicks on
               fname = imagesFile.getSelectedFile().getAbsolutePath();
               getImage();
     private void getImage()
          try
               //params = new Vector();
               //objectOut.writeObject(params);
               //objectOut.flush();
                                                                                                    // 1
               int w = ((Integer)in.readObject()).intValue();                              // 2
               int h = ((Integer)in.readObject()).intValue();
               int[] buffer = (int[])in.readObject();
               MemoryImageSource ms = new MemoryImageSource(w, h, buffer, 0, w);      // 3
               Image image = createImage(ms);                                                                                               // 4
               canvas.setImage(image);                                                                                                                   // 5
               canvas.repaint();                                                                                                                                  // 6
          catch (Exception e)
               e.printStackTrace();
               System.err.println("out error: " + e);
     public static void main (String[]args)
          if(args.length != 2)// checks whether enter 2 data e.g. localhost 222222
               System.err.println("Required parameters: <hostname>, <port number>");
               System.exit(0);
          String host = args[0];
          int port = Integer.parseInt(args[1]);
          ImageClient is = new ImageClient(host, port);
class MyCanvas extends Canvas
     // The Image to be displayed.
     Image img = null;
     public MyCanvas(Image i)
          this.resize(200, 200);
     public void setImage(Image i)
          img = scaleImage(i);
protected Image scaleImage(Image i)
     if(i == null) return null;                                                                                                              // 1
     Image scaled = null;                                                                                                                             // 2
     int w = i.getWidth(this);                                                                                                                   // 3
     int h = i.getHeight(this);
     if(w > getWidth())                                                                                                                              // 4
          scaled = i.getScaledInstance(getWidth(), -1, Image.SCALE_DEFAULT);
     else if (h > getHeight())
          scaled = i.getScaledInstance(-1, getHeight(), Image.SCALE_DEFAULT);
     else
          scaled = i;     
     return scaled;                                                                                                                                            // 5
     public void paint(Graphics g)
          if(img != null)
               g.drawImage(img, 0, 0, this);
This are the code for the ImageServer
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import javax.swing.*;
import java.net.*;
import java.io.*;
import java.util.*;
public class ImageServer
     // Declare the Vector and Image variables.
     Vector images = new Vector();
     Image img = null;
     public ImageServer()
          initImages();
          try
               start();
          catch (IOException ioe)
               System.err.println("Start failed:" + ioe);
     private void start() throws IOException
          ServerSocket ss = new ServerSocket(22222);
          while(true)
               new ImageServerConnection(ss.accept(), images).start();
     protected void initImages()
          images.addElement("robo.gif");
          images.addElement("phantom.jpg");
          images.addElement("koyomi.jpg");
     public static void main(String[] args)
          ImageServer is = new ImageServer();
class ImageServerConnection extends Thread
     // Declare the Input/Output object variables.
     Socket clientSocket = null;
     ObjectOutputStream objectOut = null;
     ObjectInputStream inObject = null;
     BufferedReader in = null;
     // Declare the data variables.
     Vector images = null;
     Image img = null;
     public ImageServerConnection(Socket client, Vector images)
          clientSocket = client;
          this.images = images;
     public void run()
          try
               newSocket();
          catch (IOException ioe)
               System.err.println("Socket failed:" + ioe);
     private void newSocket() throws IOException
          // in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));      // 1     
          objectOut = new ObjectOutputStream(clientSocket.getOutputStream());                         // 2
        inObject = new ObjectInputStream(clientSocket.getInputStream());
          sendObject(images);     
          Object input = null;
         /*                                                                                                         // 3
          String inputline;
          while ((inputline = in.readLine()) != null) {                                                  // 4
               if (images.contains(inputline))
                    sendImage(inputline);
               else break;
          try
               while((input = inObject.readObject())!= null)
                    Vector invert=(Vector)input;
                    sendImage(invert.elementAt(0).toString(), invert.elementAt(1).toString());
          catch (Exception e){}
          clientSocket.close();
     protected void sendObject(Object obj)
          try
               objectOut.writeObject(obj);
               objectOut.flush();
          catch (IOException e)
                 System.err.println("send failed.");
                 System.exit(1);
     protected void sendImage(String img_name, String inputlineOp)
          int w, h;
          img = Toolkit.getDefaultToolkit().getImage(img_name);                                        // 1
          while ((w = img.getWidth(null)) == -1){}                                                       // 2
          while ((h = img.getHeight(null)) == -1){}
          //OpSelector selector = new OpSelector();
          //img = selector.doOp(inputlineOp,img);// doOp: do the operation
          int[] buffer = new int[w * h];                                                                       // 3
          PixelGrabber px = new PixelGrabber(img, 0, 0, w, h, buffer, 0, w);     // 4
          try
               px.grabPixels();                                                                                 // 5
          } catch (InterruptedException ie)
               System.err.println("Pixel grab failed.");
          sendObject(new Integer(w));                                                                           // 6
          sendObject(new Integer(h));
          // buffer contains all the bytes for the image
          sendObject(buffer);

Answer 1

I dun know exactly which part goes
wrong...sorry...cause there are no errors when i
compile...but the image just won't appear...It isn't the menu bar. And it isn't the file chooser. Can't you write a test program that does
nothing but display an image?