Problems with default table model

Question

I am creating java editable table, and faced to problem: it "crashes" after reading data. Here is my table:

table.getTableHeader().setReorderingAllowed(false);
tableModel = new DefaultTableModel(new Object[]
{"#","1","2","3","4","5","6","7"},8);
table.setModel(tableModel);
table.getColumnModel().getColumn(0).setMaxWidth(22);

Reading from txt:

OK4.addActionListener(new ActionListener(){
    @Override
    File f = new File(fileName);
    if(f.exists()){
        try {
            tableModel = new DefaultTableModel(new Object[]{"#","1","2","3","4","5","6","7"},0);
            BufferedReader br = new BufferedReader(new FileReader(fileName));
            String line = br.readLine();
            String[] colHeaders = line.split("\\s+");
            tableModel.setColumnIdentifiers(colHeaders);
            while ((line = br.readLine()) != null) {
                String[] data = line.split("\\s+");
                tableModel.addRow(data);
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }else{
        JOptionPane.showMessageDialog(null, "this day is not saved");
    };
    table.setModel(tableModel);
    table.getColumnModel().getColumn(0).setMaxWidth(22);
});

And main problems causing my sum field:

OK3.addActionListener(new ActionListener(){
    @Override
    public void actionPerformed(ActionEvent e) {
        int sum=0;
        int number;
        Object smth;
        String Smth;
        int kint2 = table.getRowCount()-1;
        if(table.getValueAt(kint2, 1)=="total:"){

        }else{
            tableModel.addRow(new Object[]{});
            int a = table.getRowCount()-1;
            table.setValueAt("total:", a, 1);
        }
        for (int j = 2; j < 8; j++) {
            for (int i = 0; i < table.getRowCount()-1; i++) {
                smth = table.getValueAt(i,j);
                Smth = (String) smth;
                if (smth==null){
                    number=0;
                }else{
                    number=Integer.parseInt(Smth);
                }
                sum=sum+number;
            }
            table.setValueAt(sum, table.getRowCount()-1, j);
            sum=0;
        }
    }
});

Application stops calculate sum after being read from txt or calculates only first 4 rows sum. Have it something to do with my tableModel?

Thank you for answers.

Answer 1

The problem is that you add new rows with tablemodel and count rows with table. As discussed at "jTable row count VS model row count" your table won't update the rows count so always use tablemodel.getRowCount()