Assign a DefaultTableModel to a JTable (MVC)

Question

Assign a DefaultTableModel to a JTable (MVC)

Navigation

#1 by (1 votes)

1

I have a class designed to handle the events of the frames that I have created, that allows me to play with them and not instantiate code in their structure, to maintain a relationship Vista, Model, Controller . Within the mainframe I have a JTable and I would like each time the frame is started that JTable will take the structure of a DefaultTableModel created within the class of the events, by the way, I do not know if to create a single class of events and another of functions, the code of the class manager of events is the following:

public class ControladorEstudiante{

EstudianteAdmin estAdmin= new EstudianteAdmin();
EstudianteDAOImpl estDAO= new EstudianteDAOImpl();

public ControladorEstudiante(EstudianteAdmin estAdmin, MostrarEstudiante estMostrar){
    this.estDAO= estDAO;
    this.estAdmin= estAdmin;
}

public void initEstudiante(){

}

public void ListarTabla(JTable tabla){
    DefaultTableModel modeloTabla= new DefaultTableModel();
    tabla.setModel(modeloTabla);

    modeloTabla.addColumn("NOMBRE");
    modeloTabla.addColumn("MATRICULA");
    modeloTabla.addColumn("NOTA");

    Object[] columna= new Object[3];

    int objGuardados= estDAO.extraerTodos().size();

    for (int i = 0; i < objGuardados; i++) {
        columna[0]= estDAO.extraerTodos().get(i).getNombre();
        columna[1]= estDAO.extraerTodos().get(i).getMatricula();
        columna[2]= estDAO.extraerTodos().get(i).getNota();

        modeloTabla.addRow(columna);
     }
   }
}

The following is the frame code:

package comm.estudiante.interfaz;

public class EstudianteAdmin extends javax.swing.JFrame {

public EstudianteAdmin() {
    initComponents();
}

@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    menuFunciones = new javax.swing.JPopupMenu();
    submenu_Modificar = new javax.swing.JMenuItem();
    jSeparator1 = new javax.swing.JPopupMenu.Separator();
    submenu_Eliminar = new javax.swing.JMenuItem();
    jSeparator2 = new javax.swing.JPopupMenu.Separator();
    submenu_EliminarTodos = new javax.swing.JMenuItem();
    txtBuscar_estudiante = new javax.swing.JTextField();
    btnAgr_estudiante = new javax.swing.JButton();
    jScrollPane1 = new javax.swing.JScrollPane();
    tablaEstudiante = new javax.swing.JTable();

    submenu_Modificar.setText("Modificar");
    menuFunciones.add(submenu_Modificar);
    menuFunciones.add(jSeparator1);

    submenu_Eliminar.setText("Eliminar");
    menuFunciones.add(submenu_Eliminar);
    menuFunciones.add(jSeparator2);

    submenu_EliminarTodos.setText("Eliminar todos");
    menuFunciones.add(submenu_EliminarTodos);

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    btnAgr_estudiante.setIcon(new javax.swing.ImageIcon(getClass().getResource("/comm/estudiante/imagenes/Nuevo Contacto.jpg"))); // NOI18N
    btnAgr_estudiante.setText("Crear Estudiante");

    tablaEstudiante = new javax.swing.JTable(){
        public boolean isCellEditable(int rowIndex,int columnIndex){
            return false;
        }
    };
    tablaEstudiante.setModel(new javax.swing.table.DefaultTableModel(
        new Object [][] {

        },
        new String [] {

        }
    ));
    tablaEstudiante.setComponentPopupMenu(menuFunciones);
    tablaEstudiante.setFocusable(false);
    jScrollPane1.setViewportView(tablaEstudiante);

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 0, Short.MAX_VALUE)
                .addGroup(layout.createSequentialGroup()
                    .addComponent(txtBuscar_estudiante, javax.swing.GroupLayout.PREFERRED_SIZE, 229, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addComponent(btnAgr_estudiante, javax.swing.GroupLayout.PREFERRED_SIZE, 153, javax.swing.GroupLayout.PREFERRED_SIZE)))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(txtBuscar_estudiante, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(btnAgr_estudiante))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 258, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap())
    );

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

public static void main(String args[]) {

    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Windows".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(EstudianteAdmin.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(EstudianteAdmin.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(EstudianteAdmin.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(EstudianteAdmin.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }

    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new EstudianteAdmin().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private javax.swing.JButton btnAgr_estudiante;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JPopupMenu.Separator jSeparator1;
private javax.swing.JPopupMenu.Separator jSeparator2;
private javax.swing.JPopupMenu menuFunciones;
private javax.swing.JMenuItem submenu_Eliminar;
private javax.swing.JMenuItem submenu_EliminarTodos;
private javax.swing.JMenuItem submenu_Modificar;
private javax.swing.JTable tablaEstudiante;
private javax.swing.JTextField txtBuscar_estudiante;
// End of variables declaration                   

public javax.swing.JTextField getTxtBuscar_estudiante(){
    return txtBuscar_estudiante;
}

public javax.swing.JButton getBtnAgr_estudiante(){
    return btnAgr_estudiante;
}

public javax.swing.JTable getTablaEstudiante(){
    return tablaEstudiante;
}

public javax.swing.JMenuItem getSubmenu_Modificar(){
    return submenu_Modificar;
}

public javax.swing.JMenuItem getSubmenu_Eliminar(){
    return submenu_Eliminar;
}

public javax.swing.JMenuItem getSubmenu_EliminarTodos(){
    return submenu_EliminarTodos;
}

}

This is the code of the extractAll () method where DefaultTableModel fills the table:

public List<Estudiante> extraerTodos() {
    Connection con = null;
    Statement stmnt = null;
    ResultSet rs = null;
    String sql = "SELECT * FROM notas";
    List<Estudiante> lista = new ArrayList<>();    

    try {
        con = dbcon.conectar();
        stmnt = con.createStatement();
        rs = stmnt.executeQuery(sql);

        while (rs.next()) {
        lista.add(new Estudiante(
                rs.getInt("id"),
                rs.getString("nombre"),
                rs.getString("matricula"),
                rs.getInt("nota")
        ));
      }
    } catch (SQLException ex) {
        ex.printStackTrace();
    }
    return lista;
}

What I would like to know is how I can pass the ListTable method as constructor method parameter of the main frame following the MVC pattern and avoiding to instantiate code in a Vista or how can I simply do to start the frame and have the table take that DefaultTableModel .

java mvc

asked by David Calderon 10.09.2016 в 22:14

source

1 answer

Reload variable within a div? Error: reference to object not established as an instance of an object. Genexus

score 1 · Accepted Answer

Hello friend, since I do not know how to use arrayList I'll show you a possible solution using a array .

First: Create a method of type DefaultTableModel.

public DefaultTableModel consultarNotas() {

    String[] titulos = {"Id", "Nombre", "Matricula", "Nota"};
    DefaultTableModel modelo = new DefaultTableModel(null, titulos);
    String[] registros = new String[4];
    sSQL = "SELECT * FROM notas";
    try {
        st = cn.createStatement();
        rs = st.executeQuery(sSQL);
        while (rs.next()) {
            registros[0] = String.valueOf(rs.getInt("id"));
            registros[1] = rs.getString("nombre");
            registros[2] = rs.getString("matricula");
            registros[3] = String.valueOf(rs.getInt("nota"));
            modelo.addRow(registros);
        }
        return modelo;
    } catch (Exception e) {
        return null;
    }
}

Second: in the jFrame that contains your table create the function to set it.

public void cargarNotas(){
    nombreClase funciones = new nombreClase();
    try {            
        nombre_de_la_tabla.setModel(funciones.consultarNotas());
    } catch (Exception e) {
        JOptionPane.showMessageDialog(null, e,"Error al cargar las notas",JOptionPane.ERROR_MESSAGE);
    }

}

Third: Call the function from the constructor of your class

public nombreClase() {
    initComponents();
    cargarNotas();
}

with this every time you execute the jFrame the table will automatically load the model.