Tugas Pemrograman Dasar GUI

kode program:
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package proyek;
import java.util.Date;
/**
 *
 * @author Mahanda
 */
public class anulahir extends javax.swing.JFrame {

    /**
     * Creates new form anulahir
     */
    public anulahir() {
        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">//GEN-BEGIN:initComponents
    private void initComponents() {

        DateLahir = new com.toedter.calendar.JDateChooser();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        jLabel3 = new javax.swing.JLabel();
        TxtUmur = new javax.swing.JTextField();
        jButton1 = new javax.swing.JButton();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        getContentPane().setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout());
        getContentPane().add(DateLahir, new org.netbeans.lib.awtextra.AbsoluteConstraints(208, 52, 120, -1));

        jLabel1.setText("Masukkan tanggal lahir");
        getContentPane().add(jLabel1, new org.netbeans.lib.awtextra.AbsoluteConstraints(52, 58, -1, -1));

        jLabel2.setText("by anu 2004");
        getContentPane().add(jLabel2, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 286, -1, -1));

        jLabel3.setText("Umur anda sekarang adalah");
        getContentPane().add(jLabel3, new org.netbeans.lib.awtextra.AbsoluteConstraints(52, 179, -1, 28));
        getContentPane().add(TxtUmur, new org.netbeans.lib.awtextra.AbsoluteConstraints(258, 179, 70, 28));

        jButton1.setText("Proses umur");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });
        getContentPane().add(jButton1, new org.netbeans.lib.awtextra.AbsoluteConstraints(260, 110, -1, -1));

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton1ActionPerformed
        // TODO add your handling code here:
        Date lahir = DateLahir.getDate();
            Date kini = new Date();
            int umur = kini.getYear()-lahir.getYear();
            TxtUmur.setText(String.valueOf(umur));
    }//GEN-LAST:event_jButton1ActionPerformed

    /**
     * @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(anulahir.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(anulahir.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(anulahir.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(anulahir.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 anulahir().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private com.toedter.calendar.JDateChooser DateLahir;
    private javax.swing.JTextField TxtUmur;
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JLabel jLabel3;
    // End of variables declaration//GEN-END:variables
}

outputnya :