1ª app em J2ME

Comecei a desenvolver aplicações para mobile (J2ME), e a primeira aplicação é um localizador de horário de ônibus do Campo Magro, segue o fonte:

import java.util.Calendar;

import javax.microedition.lcdui.ChoiceGroup;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.StringItem;
import javax.microedition.lcdui.TextField;
import javax.microedition.midlet.MIDlet;

public class HorarioCM extends MIDlet implements CommandListener{
 private Display display;
 private Form formDados;
 private ChoiceGroup selDias;
 private ChoiceGroup selSentido;
 private TextField horario;
 private Command sair;
 private Command pesquisar;
 private Command voltar;
 private String horarioUtilCM[];
 private String horarioUtilTerminal[];
 private String horarioSabadoCM[];
 private String horarioSabadoTerminal[];
 private String horarioDomingoCM[];
 private String horarioDomingoTerminal[];
 private String horarioDisponiveis;
 
 public HorarioCM() {
  horarioUtilCM = new String[] {"04:55","05:21","05:32","05:42","05:53","06:03","06:13","06:24","06:34","06:45","06:55","07:06","07:16","07:26","07:37","07:47","08:00","08:12","08:25","09:03","09:41","10:19","10:57","11:23","11:48","12:13","12:39","13:04","13:36","14:20","14:58","15:36","16:14","16:40","16:52","17:05","17:18","17:30","17:45","17:54","18:06","18:19","18:32","18:44","18:56","19:08","19:25","20:05","20:48","21:26","22:04","22:42","23:30"};
  horarioUtilTerminal = new String[] {"05:32","05:49","05:59","06:10","06:20","06:31","06:41","06:51","07:02","07:12","07:25","07:35","07:48","08:25","09:03","09:41","10:19","11:04","11:35","12:01","12:26","12:55","13:42","14:20","14:58","15:36","16:02","16:14","16:27","16:40","16:52","17:04","17:16","17:28","17:41","17:54","18:06","18:18","18:30","18:42","18:55","19:08","19:20","19:32","19:44","20:10","20:48","21:26","22:04","22:50","23:30","24:13"};
  horarioSabadoCM = new String[] {"05:30","05:49","06:08","06:27","06:46","07:05","07:24","07:43","08:02","08:21","08:40","08:59","09:37","10:15","10:53","11:31","12:09","12:47","13:25","14:03","14:41","15:19","15:57","16:35","17:13","17:51","18:29","19:07","19:45","21:01","22:17","23:33"};
  horarioSabadoTerminal = new String[] {"05:30","06:08","06:27","06:46","07:05","07:24","07:43","08:02","08:21","08:59","09:37","10:15","10:53","11:31","12:09","12:47","13:25","14:03","14:41","15:19","15:57","16:35","17:13","17:51","18:29","19:07","19:45","20:23","21:39","22:55","24:11"};
  horarioDomingoCM = new String[] {"05:41","06:57","08:13","09:29","10:07","10:45","11:23","12:01","12:39","13:17","13:55","14:33","15:11","15:49","16:27","17:05","17:43","18:21","18:59","19:37","20:53","22:09","23:30"};
  horarioDomingoTerminal = new String[] {"05:10","06:19","07:35","08:51","10:07","10:45","11:23","12:01","12:39","13:17","13:55","14:33","15:11","15:49","16:27","17:05","17:43","18:21","18:59","20:15","21:31","22:50","24:10"};
  formDados = new Form("Horário CM");
  sair = new Command("Sair", Command.EXIT, 0);
  pesquisar = new Command("Pesquisar", Command.OK, 1);
  voltar = new Command("Voltar", Command.OK, 0);
 }

 protected void destroyApp(boolean arg0) {
  notifyDestroyed();
 }

 protected void pauseApp() {
 }

 protected void startApp() {
  display = Display.getDisplay(this);
  // SELECT DE DIAS
  String[] dias = new String[] { "Útil", "Sábado", "Domingo" };
  selDias = new ChoiceGroup("Dia:", ChoiceGroup.EXCLUSIVE, dias, null );
  formDados.append(selDias);
  // SELECT DE SENTIDO
  String[] sentidos = new String[] { "Terminal", "CM" };
  selSentido = new ChoiceGroup("Sentido:", ChoiceGroup.EXCLUSIVE, sentidos, null );
  formDados.append(selSentido);  
  // TEXTFIELD DE HORARIO
  Calendar agora = Calendar.getInstance();
  int horas = agora.get(Calendar.HOUR_OF_DAY);
  int minutos = agora.get(Calendar.MINUTE);
  horario = new TextField("Horário:",horas + ":" + minutos, 5, TextField.ANY);
  formDados.append(horario);
  // ADICIONANDO COMANDOS
  formDados.addCommand(sair);
  formDados.addCommand(pesquisar);
  formDados.setCommandListener(this);
  display.setCurrent(formDados);
 }
 
 public void commandAction(Command c, Displayable d) {
  if (c == sair) {
   destroyApp(true);
  } else if (c == pesquisar) {
   pesquisarHorario(); 
   mostrarHorario();
  } else if (c == voltar) {
   display.setCurrent(formDados);
  }
 }
 
 public void pesquisarHorario() {
  String horarioSelecionado = horario.getString();
  String hora = horarioSelecionado.substring(0,2);
  String minuto;
  if(hora.charAt(1) == ':') {
   hora = "0" + hora.charAt(0);
   minuto = horarioSelecionado.substring(2,horarioSelecionado.length());
  } else {
   minuto = horarioSelecionado.substring(3,horarioSelecionado.length());
  }
  if(minuto.length() == 1) {
   minuto = "0" + minuto;
  }
  String dia = selDias.getString(selDias.getSelectedIndex());
  String sentido = selSentido.getString(selSentido.getSelectedIndex());
  String horarioData[] = null;
  if (dia.equals("Útil") && sentido.equals("Terminal")) {
   horarioData = horarioUtilTerminal;
  } else if (dia.equals("Útil") && sentido.equals("CM")) {
   horarioData = horarioUtilCM;
  } else if (dia.equals("Sábado") && sentido.equals("Terminal")) {
   horarioData = horarioSabadoTerminal;
  } else if (dia.equals("Sábado") && sentido.equals("CM")) {
   horarioData = horarioSabadoCM;
  } else if (dia.equals("Domingo") && sentido.equals("Terminal")) {
   horarioData = horarioDomingoTerminal;
  } else if (dia.equals("Domingo") && sentido.equals("CM")) {
   horarioData = horarioDomingoCM;
  }
  boolean horarioFound = false;
  boolean horaFound = false;
  horarioDisponiveis = null;  
  int i = 0;
  while (!horarioFound && i < horarioData.length) {
   String aux_hora = horarioData[i].substring(0, 2);
   String aux_min = horarioData[i].substring(3, 5);
   if(aux_hora.equals(hora)) {
    horaFound = true;
    if(minuto.compareTo(aux_min) < 0){
     horarioFound = true;
    }
   } else if (horaFound) {
    horarioFound = true;
   }
   i++;
  }
  i=i-3;
  i=(i<0) ? 0 : i; 
  if (i < horarioData.length && horarioFound) {
   horarioDisponiveis = horarioData[i] + " - ";
   i++;
   int x = 0;
   while (x < 5 && i < horarioData.length) {
    horarioDisponiveis += horarioData[i] + " - ";
    x++;
    i++;
   }
   horarioDisponiveis = horarioDisponiveis.substring(0, (horarioDisponiveis.length()-3));
  } else {
   horarioDisponiveis = "Não foi encontrado nenhum horário";
  }
 }
 
 public void mostrarHorario() {
  Form form = new Form("Resultado da Busca");
  form.append(new StringItem(null, horarioDisponiveis));
  form.addCommand(sair);
  form.addCommand(voltar);
  form.setCommandListener(this);
  display.setCurrent(form);
 }
}