Duvida - LWUIT

package com.sun.lwuit.monografia1;


import com.sun.lwuit.layouts.BoxLayout;
import com.sun.lwuit.Button;
import com.sun.lwuit.ButtonGroup;
import com.sun.lwuit.Command;
import com.sun.lwuit.Component;
import com.sun.lwuit.Container;
import com.sun.lwuit.Display;
import com.sun.lwuit.Form;
import com.sun.lwuit.Label; // declaração das bibliotecas
import com.sun.lwuit.RadioButton; 
import com.sun.lwuit.events.ActionEvent;
import com.sun.lwuit.events.ActionListener;
import com.sun.lwuit.layouts.BoxLayout;
import com.sun.lwuit.layouts.FlowLayout;
import com.sun.lwuit.monografia1.TreeDemo;
import com.sun.lwuit.plaf.UIManager;
import com.sun.lwuit.util.Resources;
import com.sun.midp.lcdui.DisplayManager;
import java.io.IOException;
import java.io.InputStream;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Displayable;



/**
 * @author
 */
public class Temas extends Demo {
    private Display display;
    protected DisplayManager displayMgr;
    
   
    public Temas(){
   
       
     
    }
    
    
     
     
     
    public String getName() {
        return "Temas";
    }

     protected  void execute( final Form f) {
        

            
         
         f.setLayout(new BoxLayout(BoxLayout.Y_AXIS));
         final ButtonGroup group1 = new ButtonGroup();
          
         Label title = new Label("Por Favor Escolha o Tema:");
         title.getStyle().setMargin(0, 0, 0, 0);
         title.getStyle().setBgTransparency(70);
         f.addComponent(title);
         
          final RadioButton rb1 = new RadioButton("Movimento Uniforme - (MU)");
          final RadioButton rb2 = new RadioButton("Movimento Uniformemente Variado - (MUV)");
          RadioButton rb3 = new RadioButton("Tempo");
          RadioButton rb4 = new RadioButton("Acelaração");
          RadioButton rb5 = new RadioButton("Distância");
          
          group1.add(rb1);
          group1.add(rb2);
          group1.add(rb3);      
          group1.add(rb4);
          group1.add(rb5);
          
          f.addComponent(rb1);
          f.addComponent(rb2);
          f.addComponent(rb3);
          f.addComponent(rb4);
          f.addComponent(rb5);
          
        Button updateButton = new Button("----OK----");
        updateButton.setAlignment(Button.CENTER);
        updateButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent evt) {
            
                      
                //if( evt.getSource()==rb1){
                   if( rb1.isSelected() == true){
                       System.out.println("deu certo, heheh conseguieeee");
                        FontDemo p =new FontDemo();
                        
                          
                        InputStream is = getClass().getResourceAsStream("help.txt");
                        try
                        {
                            StringBuffer sb = new StringBuffer();
                            int chr,  i= 0;
                            //lê ate o final da cadeia
                            while((chr =  is.read())!=-1)
                                sb.append((char) chr);
                            
                        }
                        catch (Exception e)
                                {
                                System.out.println("não é possilvel abrir");
                                }
                         Display.init(new RenderingDemo());
                    RenderingDemo i = new RenderingDemo();
                    String help = getHelp();
                    
                                }
                           
                }
            }
        );
        Container buttonPanel = new Container(new FlowLayout(Component.CENTER));
        buttonPanel.addComponent(updateButton);
        f.addComponent(buttonPanel);
    }
          
    
    // Quando é solicitado a ajuda
    protected  String getHelp() {
        return "O estudante pode optar por escolher vários temas entre, aceleração MU, MUV, Tempo" +
                " "+
                "";
    }

}