public class NewJFrame extends javax.swing.JFrame {

    /**
     * Creates new form NewJFrame
     */ JPanel p = new JPanel();
        JTextField familyName = new JTextField(10);
        JTextField firstName = new JTextField(10);


    public NewJFrame() {
        initComponents();

        ArrayList<Pracownik> pracownicy = new ArrayList<>();

        pracownicy.add(new Pracownik(15, "asdfs", "adfsdf", 111));
        pracownicy.add(new Pracownik(15, "asdfs", "adfsdf", 111));
        pracownicy.add(new Pracownik(15, "asdfs", "adfsdf", 111));
        pracownicy.add(new Pracownik(15, "asdfs", "adfsdf", 111));

        //jTable1 = new JTable(new MyTableModel());
        MyTableModel model = new MyTableModel();
        jTable1 = new JTable(model);

        model.setModelData(pracownicy);

        jScrollPane1.setViewportView(jTable1);

        p.add(new JLabel("Family name :"));
        p.add(familyName);
        p.add(new JLabel("First name : "));
        p.add(firstName);


          }



    private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
        // TODO add your handling code here:
         JOptionPane.showConfirmDialog(null, p, "Family and first name : ", JOptionPane.OK_CANCEL_OPTION);

    }