JTable不会更新

Question

我创建了一个JTable来显示从SQL数据库中提取的约会记录。最初，表中填充了正确的数据，这意味着代码可以正常工作，但是当我激活刷新方法时，表不会更新。可以通过JPanel嵌套来实现吗？该表位于：JFrame＆gt; JPanel＆gt; JPanel＆gt; JTable中。

代码如下：

public DisplayApps(ConnectHub sqldatabase, MainPanel mp){
    this.columns = new String[]{"Type", "Appointment ID", "Patient ID", "Patient ID 2", "Room ID", "Doctor ID", "Scheduled By ID", "Date", "Time", "Length", "Has Happened", "Summary", "Date Created"};
    this.sqldatabase = sqldatabase;
    this.mp = mp;
    GridLayout mainlayout = new GridLayout(1,0);
    this.setLayout(mainlayout);
    table = new JTable();
    table.setModel(new DefaultTableModel(new Object[][]{},columns));
    refresh();
    table.setPreferredScrollableViewportSize(new Dimension(1000, 70));
    table.setFillsViewportHeight(true);
    scrollPane = new JScrollPane(table);
    add(scrollPane);
}

public Object getRowIndex(){
    int row = table.getSelectedRow();
    if(row==-1) return -1;
    return table.getValueAt(row,1);
}

public void refresh(){
    DefaultTableModel model = (DefaultTableModel) table.getModel();
    model.setRowCount(0);
    appointments = sqldatabase.getAllAppointments();   
    for(int i=0;i<appointments.size();i++){
        Object[] data = new Object[13];
        Appointment temp = appointments.get(i);
        boolean routine = true;
        if(temp instanceof RoutineAppointment)
            data[0] = "Routine";
        else{
            data[0] = "Care";
            routine = false;
        }
        data[1] = appointments.get(i).getAppID();
        if(routine){
            data[2] = ((RoutineAppointment)appointments.get(i)).getPatientID();
            data[3] = "NA";
        }
        else{
            data[2] = ((CareAppointment)appointments.get(i)).getPatientID1();
            data[3] = ((CareAppointment)appointments.get(i)).getPatientID2();
        }
        if(routine)
            data[4] = "NA";
        else
            data[4] = ((CareAppointment)appointments.get(i)).getRoomID();
        data[5] = appointments.get(i).getDoctorID();
        data[6] = appointments.get(i).getScheduledByID();
        data[7] = appointments.get(i).getDate();
        data[8] = appointments.get(i).getTime();
        data[9] = appointments.get(i).getLength();
        data[10] = appointments.get(i).isHasHappened();
        data[11] = appointments.get(i).getSummary();
        data[12] = appointments.get(i).getDateCreated().toString();
        model.addRow(data);
    }
    table.revalidate();
    table.repaint();
}