Wried? CAN YOU PLEASE TAKE A LOOK AT THIS

Question

how do you display a error massage for the user
this is what i have done but its not working
item2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());// makes it looklike win
}catch (Exception m) {     <======= i used m since e was already used
JFrame f = new JFrame();
f.setSize(50,50);
JLabel j = new JLabel(
"CANT DO THIS ON YOUR COMPUTER!!!!",JLabel.CENTER);
j.setOpaque(true);
j.setSize(200,400);
add(j);
AM I DOING ANYTHING WRONG
i think you know what i wanne do if it catches an exception i wannt it to display an error massage
saying you cant do this on your computer or soemthing
thanks in advance
AMIR

Answer 1

(WARNING - My mods to your code are a quick quick hack, but I think it shows the point)
import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Game extends JFrame{
  protected static String Key_CODE;
  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    Game g = new Game();
  Game(){
    super("Game WINDOW");
    addWindowListener(new WindowAdapter(){
      public void windowClosing(WindowEvent e){
        System.exit(0);
    buildMenu();
    pack();
    setBackground(Color.white);
    setSize(300,200);
    setVisible(true);
  private void buildMenu(){
    JMenuBar mb = new JMenuBar();
    JMenu menu = new JMenu("File");
    JMenuItem item = new JMenuItem("Exit");
    JMenuItem item2 = new JMenuItem("make it look like windows [2]");
    JMenuItem item3 = new JMenuItem("make it look like somehthing else [1]");
    JMenuItem item4 = new JMenuItem("make it look like another thing [0]");
    item.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        System.exit(0);
    item2.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        try {
          // UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());// makes it look like windows
          UIManager.LookAndFeelInfo[] info = UIManager.getInstalledLookAndFeels();
          UIManager.setLookAndFeel(info[2].getClassName());
          SwingUtilities.updateComponentTreeUI(Game.this);
        } catch (Exception m) {
          JOptionPane.showMessageDialog(null, "Cant do this on your Computer (UI 2 not supported)", "Error", JOptionPane.ERROR_MESSAGE);
    item3.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        try {
          // UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());// makes it look like windows
          UIManager.LookAndFeelInfo[] info = UIManager.getInstalledLookAndFeels();
          UIManager.setLookAndFeel(info[1].getClassName());
          SwingUtilities.updateComponentTreeUI(Game.this);
        } catch (Exception m) {
          JOptionPane.showMessageDialog(null, "Cant do this on your Computer (UI 1 not supported)", "Error", JOptionPane.ERROR_MESSAGE);
        item4.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent e){
        try {
          // UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());// makes it look like windows
          UIManager.LookAndFeelInfo[] info = UIManager.getInstalledLookAndFeels();
          UIManager.setLookAndFeel(info[0].getClassName());
          SwingUtilities.updateComponentTreeUI(Game.this);
        } catch (Exception m) {
          JOptionPane.showMessageDialog(null, "Cant do this on your Computer (UI 0 not supported)", "Error", JOptionPane.ERROR_MESSAGE);
    menu.add(item4);
    menu.add(item3);
    menu.add(item2);
    menu.add(item);
    mb.add(menu);
    setJMenuBar(mb);