Can't call or execute of different class files in a main program

Question

Hi, I got a main program which can call 3 different classes. The main program have an implicit-choice List as a starting menu. If one of the file is selected, the files will call out and display it. However, i managed to call the 1st 2 files, and the 3rd files can't display anything after selected.
I enclosed my code as below:
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class Catalogues extends Form implements CommandListener {
     private Displayable parent;
     private Display display;
     private List Cata;
     private Boots bo;
     private Higheels hHeels;
     private Sandals sand;
     private Slippers sp;
    private Command backCommand = new Command("Back", Command.BACK, 1);
    private Command viewCommand = new Command("View", Command.SCREEN, 1);
    private String[] options = {"Boots", "High Heels","Sandals", "Slippers"};
     public Catalogues(Display d, Displayable p) {
          super("Welcome to Footwear World");
          Cata = new List("Select Option", List.IMPLICIT, options, null);
          display = d;
        parent = p;
          addCommand(backCommand);
          addCommand(viewCommand);
          setCommandListener(this);
     public void commandAction(Command c, Displayable d) {
     if(d==parent && c==List.SELECT_COMMAND){
          switch(parent.getSelectedIndex()){
               case 0:
                       if(bo==null){
                          bo = new Boots(display,parent);
                         display.setCurrent(bo);
                          break;
               case 1:
                       if(hHeels==null){
                          hHeels = new Higheels(display,parent);
                         display.setCurrent(hHeels);
                          break;
               case 2:
                       if(sand==null){
                          sand = new Sandals(display,parent);
                         display.setCurrent(sand);
                          break;
               case 3:
                       if(sp==null){
                          sp = new Slippers(display,parent);
                         display.setCurrent(sp);
                          break;
               default:
         else if (c==backCommand) {
                   display.setCurrent(parent);
}If the 3rd option is selected, i'll display above mentioned layout which contain a list to select too.
After build this project on WToolkit. It shown an error message which is as below:
Project settings saved
Building "SelectCustest"
C:\WTK22\apps\SelectCustest\src\Catalogues.java:29: cannot resolve symbol
symbol : method getSelectedIndex ()
location: class javax.microedition.lcdui.Displayable
switch(parent.getSelectedIndex()){
^
1 error
com.sun.kvem.ktools.ExecutionException
Build failed
May i know what is problem am i facing now? And how to solve it.
Thanks.

Answer 1

Thanks to all for your thoughts and replies. I liked the xargs suggestion, so I tried that first. I would have (may still) try the stdin suggestion, followed by writing the grep output to a file.
xargs does work, in a way I didn't expect it to, but that could be due to my inexperience with the workings of the shell.
here's a line from my test script
cat file | grep foo | xargs java com.company.test.TEchoArghere's the contents of 'file'
123foo
abc
qafoozv
qaz
wsx
qwefoort
zxcfooh
sdfghhere's the output from the test class, which just echos any arguments
::number of args: 4
::args[0] 123foo
::args[1] qafoozv
::args[2] qwefoort
::args[3] zxcfoohso xargs appends all the values from grep into an argument list and call the java class once.
when I took xargs out of the script, nothing was passed to the class:
::number of args: 0this was really interesting and something to keep in my back pocket for future use.
Thanks again to all.
Tom