Not able to display jtable at runtime

Hello,

can anyone please help me. I am trying to create a dynamic table with checkboxes. Data are accessed from database. But it is not creating the table at runtime. It retrieves data from database properly. But I am not getting why it is not creating the table in a specified Panel (panTable). Below is the code:

int tasktotr=0;
Object[][] taskcells;
JTable ttable;

public void BuildTable() {
   Statement st;
   ResultSet rs;

   panTable.updateUI();
   String query="";
   try{
       Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
       conn=DriverManager.getConnection("jdbc:odbc:dsndbPMA","","");
       st=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
       query="select * from Task";
       rs=st.executeQuery(query);
       rs.last();
       tasktotr=rs.getRow();
       System.out.println("tasktotr="+tasktotr);
       taskcells=new Object[tasktotr][6];
       if(tasktotr>0){
           int cnt=0;
           rs.beforeFirst();
           for(int c=0;c<6;c++){
               if(c==cnt){
                   int r=0;
                   while(rs.next()){
                       if(c==0)
                           taskcells[r][c]=Boolean.FALSE;
                       else if(c==1)
                           taskcells[r][c]=rs.getString("Priority");
                       else if(c==2)
                           taskcells[r][c]=rs.getString("Subject");
                       else if(c==3)
                           taskcells[r][c]=rs.getString("Status");
                       else if(c==4)
                           taskcells[r][c]=rs.getString("DueDate");
                       else if(c==5)
                           taskcells[r][c]=rs.getString("%Complete");
                       else if(c==6)
                           taskcells[r][c]=rs.getString("Category");
                       r++;
                   }
               }
                rs.beforeFirst();
                cnt++;
           }
           rs.close();
           st.close();
           for(int i=0;i<tasktotr;i++){
               for(int j=0;j<6;j++){
                   System.out.println(taskcells[i][j]);
               }
           }
           TableModel tasktable=new TaskTableModel(tasktotr,7);
           ttable=new JTable(tasktable);

           TableColumnModel columnModel=ttable.getColumnModel();
           TableColumn column;
           for(int i=0;i<ttable.getColumnCount();i++) {
               column = columnModel.getColumn(i);
               if(i==0)
                   column.setPreferredWidth(40);
               if(i==1)
                   column.setPreferredWidth(40);
               if(i==2)
                   column.setPreferredWidth(150);
           }
           ttable.setRowHeight(18);
           ttable.setAutoResizeMode(ttable.AUTO_RESIZE_OFF);
           ttable.getTableHeader().setReorderingAllowed(false);

           JScrollPane scroll=new JScrollPane(ttable);
           scroll.setAutoscrolls(true);
           panTable.add(scroll);
           panTable.updateUI();
           panTable.revalidate();
       }
   }catch(Exception e){
       e.printStackTrace();
       JOptionPane.showMessageDialog(null,e.getMessage(),"Error!!",1);
   }
}


class TaskTableModel extends AbstractTableModel{
    int totrow,totcol;
    public TaskTableModel(int r,int c){
        totrow=r;
        totcol=c;
    }
    @Override
    public int getRowCount() {
        return totrow;
    }
    @Override
    public int getColumnCount() {
        return totcol;
    }

    public Object getValueAt(int r,int c) {
        return taskcells[r][c];
    }

    public String getColumnName(int c){
        if(c==0)
            return "Icon";
        else if(c==1)
            return "Priority";
        else if(c==2)
            return "Subject";
        else if(c==3)
            return "Status";
        else if(c==4)
            return "Due Date";
        else if(c==5)
            return "% Completed";
        else if(c==6)
            return "Category";
        else
            return "";
    }

    public void setValueAt(Object obj,int r,int c){

        taskcells[r][c]=obj;
        fireTableCellUpdated(r, c);
    }

    //Edit only first column.
    public boolean isCellEditable(int r,int c){
        return c==0;
    }

    //used to display checkbox else it will show true/false text instead of checkbox. n
    public Class getColumnClass(int c) {
        return getValueAt(0, c).getClass();
    }

}