JAVA:How to update/refresh Table after changes made into database

Question

I'm new to java and DBMS. I'm trying to update/refresh the JTable after any changes made into the H2 database when user clicks a same button to show JTable and after writing data into database(when write button is clicked). I tried some methods and read some posts but couldn't find anything essential to my program. The code below illustrates my problem.

This is the method used to read from database and show it on JTable

public void readActiveData() throws IOException, InstantiationException, IllegalAccessException, SQLException {       

    try {
        st = conn.createStatement();
    } catch (SQLException sqlex) {
        JOptionPane.showMessageDialog(null, "Can't connect to DB. " + sqlex);
        dispose();
    }

    try {
        rs = st.executeQuery("SELECT * FROM main_data WHERE expirationDate > NOW() + 1;");
        rs.beforeFirst();

        while (rs.next()) {
            int id = rs.getInt(1);
            String ovogNer = rs.getString(2);
            String regNum = rs.getString(3);
            String itemName = rs.getString(4);
            String note = rs.getString(5);
            int zHemjee = rs.getInt(6);
            int hvv = rs.getInt(7);
            int hugatsaa = rs.getInt(8);
            today = rs.getDate(9);
            int totalPay = rs.getInt(10);
            expirationDate = rs.getDate(11);
            rows++;
        }
        regData = new Object[rows][11];

        Object[] Colheads = {"Бүртгэлийн дугаар", "Овог нэр", "Регистрийн дугаар", "Барьцаа",
             "Тэмдэглэл", "Зээлийн хэмжээ", "Хүү (%)", "Хугацаа", "Огноо", "Нийт төлөх", "Дуусах хугацаа"};

        rs = st.executeQuery("SELECT * FROM main_data WHERE expirationDate >   NOW() + 1;");

        for (int i1 = 0; i1 < rows; i1++) {
            rs.next();

            for (int j1 = 0; j1 < 11; j1++) {
                regData[i1][j1] = rs.getString(j1 + 1);
            }
        }
        model = new DefaultTableModel(regData, Colheads);
        table = new JTable(model);
        int v = ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED;
        int h = ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED;
        JScrollPane jsp = new JScrollPane(table, v, h);
        activeDataPanel.add(jsp);
        rs.close();
        st.close();
        conn.close();
    }

And this is the method i'm using to write data into the database

public void writeDataIntoDB() throws InstantiationException, IllegalAccessException {

    ResultSet rs = null;
    Connection conn = null;
    Statement st = null;
    PreparedStatement pst = null;

    final String URL = "jdbc:h2:~/registDB";
    final String USER = "admin";
    final String PASS = "password";
    LocalDate currentDate = LocalDate.now();
    String input = hugatsaaFld.getText();
    long addDays = Long.parseLong(input);
    expiration = currentDate.plusDays(addDays);
    expirationDate = java.sql.Date.valueOf(expiration);

    try {

        Class.forName("org.h2.Driver").newInstance();

        conn = DriverManager.getConnection(URL, USER, PASS);

        String sql = "INSERT INTO main_data(ovogNer,regNum,itemName,note,zHemjee,hvv,hugatsaa,date,totalPay,expirationDate)"
                + "VALUES"
                + "(?,?,?,?,?,?,?,?,?,? )";
        pst = conn.prepareStatement(sql);
        pst.setString(1, getOvogNer());
        pst.setString(2, getRegNum());
        pst.setString(3, getItemName());
        pst.setString(4, getNote());
        pst.setInt(5, +getzHemjee());
        pst.setInt(6, +getHvv());
        pst.setLong(7, +getHugatsaa());
        pst.setDate(8, java.sql.Date.valueOf(LocalDate.now()));
        pst.setDouble(9, getTotalPay());
        pst.setDate(10, expirationDate);
        pst.executeUpdate();
        pst.close();
        conn.close();
    } catch (SQLException se) {
        JOptionPane.showMessageDialog(null, "Error: " + se);
    } catch (ClassNotFoundException ex) {
        ex.printStackTrace();
    }
}

Answer 1

This question has been answered here

but it comes down to clearing and rerendering your JTable object. i.e. refresh, the post above explains it quite nicely.

Hope you get it right.