Unable to understand how to remove exception raised here.

[Yaki Kumar]

Below is the code for my ChatManager Class.

package ui;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Observer;
import javax.swing.BorderFactory;
import javax.swing.DefaultListModel;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListCellRenderer;
import javax.swing.ListSelectionModel;
import libPack.MyVCardProvider;
import org.jivesoftware.smack.Connection;
import org.jivesoftware.smack.provider.ProviderManager;

/**
 *
 * @author vikesh
 */
public abstract class ChatManager extends JPanel implements Observer {

    protected HashMap<String, String> users;
    protected List<String> onlineUsers;
    protected Connection conn;
    protected JList chatList;
    protected JScrollPane chatListScroller;
    private DefaultListModel chatListModel;

    protected abstract void init();

    public ChatManager() {
        super(new BorderLayout(0, 0));
        chatListModel = new DefaultListModel();
        chatList = new JList();
        chatList.setModel(chatListModel);
        chatList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        chatList.setCellRenderer(new BuddyRenderer());
        chatListScroller = new JScrollPane(chatList);
        chatListScroller.setViewportView(chatList);
        add(chatListScroller, BorderLayout.CENTER);
        users = new HashMap<String, String>();
        onlineUsers = new ArrayList<String>();
        ProviderManager.getInstance().addIQProvider("vCard", "vcard-temp", new MyVCardProvider());
    }

    public Connection getConn() {
        return conn;
    }

    public void setConn(Connection conn) {
        this.conn = conn;
    }

    protected void addBuddy(ChatBuddy buddy) {
        chatListModel.addElement(ui);
    }

    private class BuddyRenderer extends JPanel implements ListCellRenderer {

        private JLabel nameLabel, avatarLabel, statusLabel;
        private ChatBuddy chatBuddy;

        public BuddyRenderer() {
            super();
            setLayout(new BorderLayout(0, 0));
            setBorder(BorderFactory.createLineBorder(Color.LIGHT_GRAY, 1));
            setOpaque(true);
        }

        @Override
        public Component getListCellRendererComponent(JList list, Object value,
                int index, boolean isSelected, boolean cellHasFocus) {
            System.out.println("Class of value: " + value.getClass());
            chatBuddy = (ChatBuddy) value;
            nameLabel = new JLabel(value.toString());
            avatarLabel = new JLabel(chatBuddy.getAvatarIcon());
            statusLabel = new JLabel(chatBuddy.getStatusIcon());
            setOpaque(true);
            add(avatarLabel, BorderLayout.EAST);
            add(nameLabel, BorderLayout.CENTER);
            add(statusLabel, BorderLayout.WEST);
            if (isSelected) {
                setBackground(Color.LIGHT_GRAY);
            } else {
                setBackground(Color.WHITE);
            }
            return this;
        }
    }
}

I wrote a FChatManager - for Facebook Chat as below:

package ui.facebook;

import convUtils.Base64;
import java.awt.Image;
import java.util.Collection;
import java.util.Observable;
import java.util.logging.Level;
import java.util.logging.Logger;
import libPack.MyVCard;
import org.jivesoftware.smack.Roster;
import org.jivesoftware.smack.RosterEntry;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.packet.Message;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smack.packet.Presence;
import org.jivesoftware.smack.packet.Presence.Type;
import ui.ChatBuddy;
import ui.ChatManager;

/**
 *
 * @author vikesh
 */
public class FChatManager extends ChatManager {

    private Collection<RosterEntry> entries;
    private Roster roster;

    public void init() {

        new Thread() {

            public void run() {
                roster = conn.getRoster();
                System.out.println("Connection authenticated? " + conn.isAuthenticated());
                try {
                    System.out.println("Getting Roster Entries");
                    System.out.println("Thread sleeping...");
                    Thread.sleep(5000);
                    entries = roster.getEntries();
                    System.out.println("Got Roster Entries");
                    for (RosterEntry entry : entries) {
                        System.out.println("User: " + entry.getUser() + "Name: " + entry.getName());
                        users.put(entry.getUser(), entry.getName());
                    }
                    MyVCard vCard = new MyVCard();
                    for (String avl : onlineUsers) {
                        try {
                            vCard.load(conn, avl);
                        } catch (XMPPException ex) {
                            Logger.getLogger(FChatManager.class.getName()).log(Level.SEVERE, null, ex);
                        }
                        String avatarString = vCard.getAvatarString();
                        Image image = null;
                        if (avatarString != null) {
                            avatarString = avatarString.replaceAll("\n", "");
                            image = Base64.getImage(avatarString); //avatarString is Base64 String value of Image
                        }
                        ChatBuddy buddy = new ChatBuddy(users.get(avl), avl, image, ChatBuddy.STATUS.AVAILABLE);
                        addBuddy(buddy);
                    }
                } catch (InterruptedException ex) {
                    Logger.getLogger(FChatManager.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        }.start();
    }

    public String getName() {
        return "Facebook";
    }

    @Override
    public void update(Observable o, Object arg) {
        Packet packet = null;
        if (arg instanceof Packet) {
            packet = (Packet) arg;
            if (packet instanceof Presence) {
                Presence presence = (Presence) packet;
                Type type = presence.getType();
                System.out.println("Presence received " + packet.getFrom() + " Type: " + type);
                if (type == Type.available) {
                    onlineUsers.add(packet.getFrom());
                } else if (type == Type.unavailable) {
                    onlineUsers.remove(packet.getFrom());
                }
            } else if (arg instanceof Message) {
                System.out.println("Message received");
            }
        }
    }
}

Further I have ChatBuddy class that represents User/Buddy available for chat ... I get it when I receive Presence packet .

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package ui;

import java.awt.Image;
import java.util.Observable;
import java.util.Observer;
import javax.swing.Icon;
import javax.swing.ImageIcon;

/**
 *
 * @author vikesh
 */
public class ChatBuddy implements Observer {

    @Override
    public void update(Observable o, Object arg) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    public enum STATUS {

        AVAILABLE, UNAVAILABLE, AWAY, BUSY;
    }
    private String buddyName, buddyId;
    private Image buddyImage;
    private STATUS status;
    private Icon avatarIcon, statusIcon;
    public static final Icon DEFAULT_ICON = new ImageIcon("generic-avatar.gif");
    public static final Icon AVL_ICON = new ImageIcon("available.png");
    public static final Icon BUSY_ICON = new ImageIcon("busy.png");
    public static final Icon AWAY_ICON = new ImageIcon("away.png");

    public Icon getAvatarIcon() {
        return avatarIcon;
    }

    public String getBuddyId() {
        return buddyId;
    }

    public Image getBuddyImage() {
        return buddyImage;
    }

    public Icon getStatusIcon() {
        return statusIcon;
    }

    public String getBuddyName() {
        return buddyName;
    }

    public void setStaus(STATUS changedStat) {
        status = changedStat;
        if (changedStat == STATUS.AVAILABLE) {
            statusIcon = AVL_ICON;
        } else if (changedStat == STATUS.AWAY) {
            statusIcon = AWAY_ICON;
        } else if (changedStat == STATUS.BUSY) {
            statusIcon = BUSY_ICON;
        }
    }

    public STATUS getStatus() {
        return status;
    }

    public ChatBuddy(String name, String userId, Image avatar, STATUS currStatus) {
        this.buddyName = name;
        this.buddyImage = avatar;
        this.buddyId = userId;
        if (avatar != null) {
            avatarIcon = new ImageIcon(avatar);
        } else {
            avatarIcon = DEFAULT_ICON;
        }
        status = currStatus;
    }

    @Override
    public String toString() {
        return this.buddyName;
    }
}

What I wanted to do is add/remove users, along with their images (which I could get from vCard) from a List in the ChatManager as and when they become available/unavailable. The problem is, I keep getting following...


Class of value: class javax.swing.plaf.basic.BasicPanelUI
Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: javax.swing.plaf.basic.BasicPanelUI cannot be cast to ui.ChatBuddy
at ui.ChatManager$BuddyRenderer.getListCellRendererComponent(ChatManager.java:84)
at javax.swing.plaf.basic.BasicListUI.updateLayoutState(BasicListUI.java:1344)
at javax.swing.plaf.basic.BasicListUI.maybeUpdateLayoutState(BasicListUI.java:1294)
at javax.swing.plaf.basic.BasicListUI.getPreferredSize(BasicListUI.java:561)
at javax.swing.JComponent.getPreferredSize(JComponent.java:1634)
at javax.swing.ScrollPaneLayout.layoutContainer(ScrollPaneLayout.java:769)
at java.awt.Container.layout(Container.java:1421)
at java.awt.Container.doLayout(Container.java:1410)
at java.awt.Container.validateTree(Container.java:1507)
at java.awt.Container.validate(Container.java:1480)
at javax.swing.RepaintManager.validateInvalidComponents(RepaintManager.java:669)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:124)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:642)
at java.awt.EventQueue.access$000(EventQueue.java:85)
at java.awt.EventQueue$1.run(EventQueue.java:603)
at java.awt.EventQueue$1.run(EventQueue.java:601)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:612)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122).......


What I don't get is I am adding a ChatBuddy at Line Number 60 in FChatManager to the List.. via ChatManager's addBuddy(ChatBuddy buddy) at Line No. 60 in ChatManager but javax.swing.plaf.basic.BasicPanelUI is what it gets... which is all the reason I think its failing. How could I get rid of this?? I don't have in depth knowledge of Java
Please I need help... after so long I have zeroed to using JList to display users online and also wrote a Simple Program and adding some custom Object to List.. there it said that the object received was the one that I had added.
Thanks.

[Michael Dunn]

wild guess

protected void addBuddy(ChatBuddy buddy) {
        chatListModel.addElement(ui);
}

maybe it should be
chatListModel.addElement(buddy);

[Yaki Kumar]

Thanks, Dunn. It was a silly mistake.
Just one more thing? Do you think, my design is kind of Okay?? Like doing most of the thing is an abstract class (Chat Manager)... and doing only Specific Things .. like related to Facebook in FChatManager which extends ChatManager??
Thanks a LOT.