como saco un dialogo desde un menu

[dogduck]

a mi se me ocurre lo siguiente :

//Creo unos contadores
public Integer w98=0,wxp=0,linux=0;

//Tengo un choice
choice1 = new java.awt.Choice();
choice1.add("Elige Sistema Operativo");
choice1.add("Windows 98");
choice1.add("Windows XP");
choice1.add("Linux");

//Evento al cambiar de estado un elemento del choice
private void choice1ItemStateChanged(java.awt.event.ItemEvent evt) {
if (choice1.getSelectedItem()=="Windows 98") {w98++;}
if (choice1.getSelectedItem()=="Windows XP") {wxp++;}
if (choice1.getSelectedItem()=="Linux") {linux++;}
}

Lo he probado con el siguiente ejemplo implementado en NetBeans

Código:

/*
 * Ejemplo.java
 *
 * Created on 21 de enero de 2006, 4:53
 */

package general;

/**
 *
 * @author  DogDuck
 */
public class Ejemplo extends javax.swing.JFrame {
    public Integer w98=0,wxp=0,linux=0;
    /** Creates new form Ejemplo */
    public Ejemplo() {
        initComponents();
    }
    
    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    // <editor-fold defaultstate="collapsed" desc=" Generated Code ">
    private void initComponents() {
        choice1 = new java.awt.Choice();
        choice1.add("Elige Sistema Operativo");
        choice1.add("Windows 98");
        choice1.add("Windows XP");
        choice1.add("Linux");
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        jLabel3 = new javax.swing.JLabel();
        jTextField1 = new javax.swing.JTextField();
        jTextField2 = new javax.swing.JTextField();
        jTextField3 = new javax.swing.JTextField();

        getContentPane().setLayout(null);

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        choice1.addItemListener(new java.awt.event.ItemListener() {
            public void itemStateChanged(java.awt.event.ItemEvent evt) {
                choice1ItemStateChanged(evt);
            }
        });

        getContentPane().add(choice1);
        choice1.setBounds(30, 30, 210, 20);

        jLabel1.setText("w98");
        getContentPane().add(jLabel1);
        jLabel1.setBounds(40, 80, 30, 14);

        jLabel2.setText("wxp");
        getContentPane().add(jLabel2);
        jLabel2.setBounds(40, 110, 30, 14);

        jLabel3.setText("linux");
        getContentPane().add(jLabel3);
        jLabel3.setBounds(40, 140, 30, 14);

        jTextField1.setText("0");
        getContentPane().add(jTextField1);
        jTextField1.setBounds(90, 80, 12, 20);

        jTextField2.setText("0");
        getContentPane().add(jTextField2);
        jTextField2.setBounds(90, 110, 12, 20);

        jTextField3.setText("0");
        getContentPane().add(jTextField3);
        jTextField3.setBounds(90, 140, 12, 20);

        pack();
    }// </editor-fold>

    private void choice1ItemStateChanged(java.awt.event.ItemEvent evt) {
// TODO add your handling code here:
        if (choice1.getSelectedItem()=="Windows 98") {w98++;jTextField1.setText(w98.toString());}
        if (choice1.getSelectedItem()=="Windows XP") {wxp++;jTextField2.setText(wxp.toString());}
        if (choice1.getSelectedItem()=="Linux") {linux++;jTextField3.setText(linux.toString());}
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new Ejemplo().setVisible(true);
            }
        });
    }
    
    // Variables declaration - do not modify
    private java.awt.Choice choice1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    private javax.swing.JTextField jTextField1;
    private javax.swing.JTextField jTextField2;
    private javax.swing.JTextField jTextField3;
    // End of variables declaration
    
}

Espero te valga de algo