So this is my first attempt at a GUI in swing, and so far things seem to have been going somewhat smoothly.
However I am un-able to update a JList named objectsL.
I imagine this is because I have already added it to a panel?
So, now Im am very lost, and any help would be appreciated.
(Oh and Im very sorry for my messy code)

import javax.swing.AbstractButton;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.ImageIcon;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.Dimension;


import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.*;
import javax.swing.border.*;

import javax.swing.*;
import java.awt.event.*;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.util.*;

/* 
 * ButtonDemo.java requires the following files:
 *   images/right.gif
 *   images/middle.gif
 *   images/left.gif
 */
public class test3 extends JPanel
                        implements ActionListener, ListSelectionListener, KeyListener, FocusListener{
   private master m;                         
   JList objectsL;// = new JList();
   JList typesL;// = new JList();
   JTextField url;
   JTextField keyWord;
   DefaultListModel listModel;
    public test3() {
        m =new master();
        JPanel pane = new JPanel();
        pane.setLayout(new GridBagLayout());
         url = new JTextField("URL goes here");
         url.setForeground(Color.gray);
         JButton search = new JButton("Search");
         
         search.setActionCommand("search");
         search.addActionListener(this);        
         search.setToolTipText("Opens URL, and searches for links.");
         
         
         GridBagConstraints c = new GridBagConstraints();
         c.fill = GridBagConstraints.HORIZONTAL;
         c.gridx = 0;
         c.gridy = 0;
         c.weightx= 0.9;
         pane.add(url,c);
         c.gridx=1;
         //c.fill = 0;
         c.weightx= 0.1;
         pane.add(search,c);
         //relating to lists------------------
         listModel = new DefaultListModel();
         listModel.addElement("try");
         String[] objects = {};//"empty","empty","empty"};
        objectsL = new JList(objects);
        objectsL.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
        objectsL.setLayoutOrientation(JList.VERTICAL);
        objectsL.setVisibleRowCount(20);
        
        
        
        String[] types ={"All","All image types","jpg","png","bmp","tiff","gif","All video types","mpg","mpeg","avi","rmvb","mp4"};
        //DefaultListModel temp = new DefaultListModel();
        //for(int i=0;i<types.length;i++)
          //  temp.addElement(types[i]);
        typesL = new JList(types);    
        typesL.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        typesL.setLayoutOrientation(JList.VERTICAL);
        typesL.setVisibleRowCount(1);
        
        objectsL.setToolTipText("List of Links");
        typesL.setToolTipText("Common file types");
        
        objectsL.addListSelectionListener(this);
        typesL.addListSelectionListener(this);
        
        JScrollPane typesLP = new JScrollPane(typesL);
        JScrollPane objectsLP = new JScrollPane(objectsL);
        
        
        JPanel lists = new JPanel();
        lists.setLayout(new GridLayout(1,2));
        
        Border loweredetched = BorderFactory.createEtchedBorder(EtchedBorder.LOWERED);
        
        objectsL.setBorder(BorderFactory.createTitledBorder(
                        loweredetched, "Links"));
        typesL.setBorder(BorderFactory.createTitledBorder(
               loweredetched, "File types"));       
        
        lists.add(objectsLP);
        lists.add(typesLP);
        c.gridy=1;
        c.gridx=0;
        c.gridwidth=2;
        c.fill = GridBagConstraints.BOTH;
        c.weightx=1.0;
        c.weighty=1.0;
        pane.add(lists,c); 
        //--------------------------------------------------------------------------
        JPanel otPan = new JPanel();
        otPan.setLayout(new GridLayout(1,2,30,0));
        JButton downloadMulti = new JButton("Download");
        downloadMulti.setActionCommand("download");
        downloadMulti.addActionListener(this);
        downloadMulti.setToolTipText("Use when downloading multiple items.");
        keyWord = new JTextField("Keyword");
        keyWord.addKeyListener(this);
        keyWord.addFocusListener(this);
        keyWord.setForeground(Color.gray);
        otPan.add(downloadMulti,c);
        otPan.add(keyWord,c);

        c.fill= GridBagConstraints.HORIZONTAL;
        c.anchor = GridBagConstraints.PAGE_END;
        c.gridy = 2;
        c.weighty=0;
        pane.add(otPan,c);  
        
        add(pane);
        
        String[] temp = {"updated","updated"};
        objectsL = new JList(temp);
    }
//---------------------Button evnts----------------------------
    public void actionPerformed(ActionEvent e) {
        if ("search".equals(e.getActionCommand()))
        {
            System.out.println(url.getText()); 
            
            if(m.findObjects(url.getText()))
                {
                    updateList(objectsL, m.getObjects());
                    System.out.println(m.getObjects().get(1));
                }
        }
        else if("download".equals(e.getActionCommand()))
            System.out.println("Downloading");
    }
//--------------------------------------------------------------
//------------------------List Events---------------------------    
     public void valueChanged(ListSelectionEvent e) 
     {
        if (e.getValueIsAdjusting())
            return;
        else
        {
            JList theList = (JList)e.getSource();
            if(theList==objectsL)
                System.out.println("objects was hit");
            else if(theList == typesL)
                System.out.println("types was hit");
        } 
     }
//--------------------------------------------------------------
//------------------------Key events---------------------------     
     public void keyTyped(KeyEvent e) {
       System.out.println("you entered a key");
         updateList(objectsL, m.getObjects(keyWord.getText()));
    }  
     public void keyPressed(KeyEvent e) {

    }
    
    public void keyReleased(KeyEvent e) {
        
    }
//--------------------------------------------------------------
//------------------------Focus events-------------------------    
    public void focusGained(FocusEvent e) 
    {//both text field use focus listener
        if(url.equals(e.getSource()))//does nto work yet
        {
            url.setForeground(Color.black);
            url.selectAll();
        }
        else
        {
            keyWord.setForeground(Color.black);
            keyWord.selectAll();
            
        }
    }

    public void focusLost(FocusEvent e) {
    
    }
//--------------------------------------------------------------

 public void updateList(JList list, ArrayList objs)//your standard list update method
    {
       DefaultListModel listModel = (DefaultListModel)list.getModel();
        listModel.clear();
        for(int i=0; i<objs.size(); i++)
        {
            listModel.addElement((String)objs.get(i));
        }
    }

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path) {
        java.net.URL imgURL = test3.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }

    /**
     * Create the GUI and show it.  For thread safety, 
     * this method should be invoked from the 
     * event-dispatching thread.
     */
    private static void createAndShowGUI() {

        //Create and set up the window.
        JFrame frame = new JFrame("test3");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        test3 newContentPane = new test3();
        newContentPane.setLayout(new GridLayout());
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI(); 
            }
        });
    }
}

Let me focus the question.
When updating a JList would this code do the trick:

public void updateList(JList list, ArrayList objs)
    {
        DefaultListModel listModel = (DefaultListModel)list.getModel();
        listModel.clear();
        for(int i=0; i<objs.size(); i++)
        {
            listModel.addElement((String)objs.get(i));
        }
    }

That was the method I used to update a JList when using a GUI based off of BreezySwing. However this throws a classCastException error, when used in a GUI based off swing.

This question has already been answered. Start a new discussion instead.