How to implement custom property pages for custom feature renderers

package arcgis.sample;
import java.awt.Rectangle;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.border.TitledBorder;

public class PointDispersalRendererUI extends JFrame{
    private JPanel jContentPane = null;
    private JLabel jLabel = null;
    private JTextField jTextField = null;
    private JPanel jPanel = null;
    private JLabel jLabel1 = null;
    /**
     * This is the default constructor.
     */
    public PointDispersalRendererUI()throws Exception{
        initialize();
    }
    /**
     * This method initializes the frame
     * @return void.
     */
    private void initialize()throws Exception{
        this.setSize(424, 254);
        this.setResizable(false);
        this.setContentPane(getJContentPane());
        this.setTitle("Dispersal Property Page");

    }
    /**
     * This method creates a ContentPane for the panel
     * @return javax.swing.JPanel.
     */
    private JPanel getJContentPane()throws Exception{
        if (jContentPane == null){
            jContentPane = new JPanel();
            jContentPane.setLayout(null);
            jContentPane.add(getJPanel(), null);
        }
        return jContentPane;
    }
    /**
     * This method creates a panel 
     * 
     * @return javax.swing.JPanel. 
     */
    private JPanel getJPanel(){
        if (jPanel == null){
            jPanel = new JPanel();
            jPanel.setLayout(null);
            jPanel.setBounds(new Rectangle(8, 14, 405, 206));
            TitledBorder titled = new TitledBorder("Change Dispersal Ratio");
            jPanel.setBorder(titled);

            //Create a label that displays Dispersal Ratio.
            jLabel = new JLabel();
            jLabel.setText("Dispersal Ratio");
            jLabel.setBounds(new Rectangle(14, 97, 83, 27));
            //Add label to the panel.
            jPanel.add(jLabel, null);
            //Create and add a text field to accept dispersal ratio value to the panel.
            jPanel.add(getJTextField(), null);

            //Create an information label.
            jLabel1 = new JLabel();
            jLabel1.setBounds(new Rectangle(12, 35, 385, 40));
            jLabel1.setText(
                "This ratio affects how far the marker symbol is moved from its original location.");
            //Add label to the panel.
            jPanel.add(jLabel1, null);
        }
        return jPanel;
    }
    /**
     * This method creates a text field to accept the dispersal ratio for pointDispersalRenderer
     * @return javax.swing.JTextField. 
     */
    public JTextField getJTextField(){
        if (jTextField == null){
            jTextField = new JTextField();
            jTextField.setBounds(new Rectangle(107, 98, 100, 27));
        }
        return jTextField;
    }
    static{
        try{
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        }
        catch (Exception e){
            e.printStackTrace();
        }
    }
}

//The annotation for the custom renderer property page.
@ArcGISExtension(categories = {
    ArcGISCategories.ESRIRendererPropertyPages
}

)
//The Java class extends BaseCustomRendererPropertyPage.
public class PointDispersalPropertyPage extends BaseCustomRendererPropertyPage{

}

//Property page Java class for the PointDispersalRenderer.

//The annotation and the assigned category attribute ESRIRendererPropertyPage.
//The Java class extends BaseCustomRendererPropertyPage.
@ArcGISExtension(categories = {
    ArcGISCategories.ESRIRendererPropertyPages
}

)public class PointDispersalPropertyPage extends BaseCustomRendererPropertyPage{
    PointDispersalPropertyPageUI pointPropertyPageUI;

    //Provides a name on the left pane of the dialog box.
    @Override public String getName()throws IOException, AutomationException{
        return "PointDispersal";
    }

    //Provides a category to show the custom renderer on the left pane.
    @Override public String getType()throws IOException, AutomationException{
        return "Dispersal Renderer";
    }


    //Specifies the position of the category defined by getType() method on the left pane.
    @Override public int getPriority()throws IOException, AutomationException{
        return 0;
    }

    //Provides a description of the custom renderer on top of the property page.
    @Override public String getDescription()throws IOException, AutomationException{
        return "PointDispersal Renderer Property Page";
    }

    //Provides a preview image of the renderer.
    @Override public int getPreviewImage()throws IOException, AutomationException{
        PictureMarkerSymbol picMarker = new PictureMarkerSymbol();
        picMarker.createMarkerSymbolFromFile(esriIPictureType.esriIPictureBitmap, 
            "C:\\temp\\DispersedPoints.bmp");
        int handel = picMarker.getPicture().getHandle();
        return handel;
    }

    //Initializes the GUI form that provides UI controls for renderer properties.
    public JFrame initGUI(IFeatureRenderer arg0){

        try{
            pointPropertyPageUI = new PointDispersalPropertyPageUI();
        }
        catch (Exception e){
            e.printStackTrace();
        }
        return pointPropertyPageUI;
    }


    //The renderer properties are defined based on the values 
    //added by the user on the GUI form.
    @Override public void apply(IFeatureRenderer featRenderer){
        PointDispersalRenderer pointRenderer = (PointDispersalRenderer)featRenderer;
        String dispersalRatio = pointPropertyPageUI.getJTextField().getText();
        pointRenderer.setDispersalRatio(Double.parseDouble(dispersalRatio));
    }

    //Specifies the associated custom renderer of the property page.

    @Override public Class getCustomRendererDef(){
        return customrenderer.pointdispersal.PointDispersalRenderer.class;
    }
} //End of class.