Cálculo de las potencias de 2 hasta ese número "preparando examen"






/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
* Fuente:
* http://garabatoslinux.net/validacion-de-jtextfield-textfield-numerico-binario-o-solo-letras.html
*/
package unidad4u2e19;

import javax.swing.JOptionPane;

/**
*
* @author juan
*/
public class Potencias extends javax.swing.JFrame {

    /**
     * Creates new form Potencias
 
    */
    public Potencias() {
        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.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        txtNumero = new javax.swing.JTextField();
        btnCalcular = new javax.swing.JButton();
        jScrollPane1 = new javax.swing.JScrollPane();
        txtPotencias = new javax.swing.JTextArea();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        txtNumero.setHorizontalAlignment(javax.swing.JTextField.RIGHT);
        txtNumero.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                txtNumeroActionPerformed(evt);
            }
        });
        txtNumero.addKeyListener(new java.awt.event.KeyAdapter() {
            public void keyTyped(java.awt.event.KeyEvent evt) {
                txtNumeroKeyTyped(evt);
            }
        });

        btnCalcular.setMnemonic('C');
        btnCalcular.setText("Calcular potencias");
        btnCalcular.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                btnCalcularActionPerformed(evt);
            }
        });

        txtPotencias.setColumns(20);
        txtPotencias.setRows(5);
        jScrollPane1.setViewportView(txtPotencias);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(122, 122, 122)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                    .addComponent(txtNumero)
                    .addComponent(btnCalcular, javax.swing.GroupLayout.DEFAULT_SIZE, 130, Short.MAX_VALUE))
                .addContainerGap(148, Short.MAX_VALUE))
            .addComponent(jScrollPane1, javax.swing.GroupLayout.Alignment.TRAILING)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(27, 27, 27)
                .addComponent(txtNumero, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(37, 37, 37)
                .addComponent(btnCalcular, javax.swing.GroupLayout.PREFERRED_SIZE, 23, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(18, 18, 18)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 153, Short.MAX_VALUE))
        );

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

    private void txtNumeroKeyTyped(java.awt.event.KeyEvent evt) {
       char car = evt.getKeyChar();
      
       if(txtNumero.getText().length()>=2) evt.consume();
       if((car<'0' || car>'9')) evt.consume();
    }

    private void btnCalcularActionPerformed(java.awt.event.ActionEvent evt) {
        String tmp = "";
        txtPotencias.setText("");
        try {
            int ult= Integer.parseInt(txtNumero.getText());
            for (int i = 0; i <= ult ; i++) {
                tmp += String.valueOf(Math.pow(2, i)) ;
                if (i!=ult) tmp+=" ,";
            }
        } catch (Exception e) {
            JOptionPane.showMessageDialog(this, e);
        }



        txtPotencias.setText(tmp);
    }

    private void txtNumeroActionPerformed(java.awt.event.ActionEvent evt) {
        // TODO add your handling code here:
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /*
         * Set the Nimbus look and feel
         */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /*
         * If Nimbus (introduced in Java SE 6) is not available, stay with the
         * default look and feel. For details see
         * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(Potencias.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Potencias.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Potencias.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Potencias.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /*
         * Create and display the form
         */
        java.awt.EventQueue.invokeLater(new Runnable() {

            public void run() {
                new Potencias().setVisible(true);
            }
        });
    }
    // Variables declaration - do not modify
    private javax.swing.JButton btnCalcular;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTextField txtNumero;
    private javax.swing.JTextArea txtPotencias;
    // End of variables declaration
}