java-JTable在添加新行时不会更新

public class InvoicesTable extends JPanel {
    private static final String[] cols = {"No.", "Date", "Customer", "Total"} ;
    private static Object[][]data ;

    private static   DefaultTableModel invoicesTableModel;
    private static   JTable invoicesTable;

    public InvoicesTable() {
        invoicesTableModel = new DefaultTableModel(cols,0);
        invoicesTable = new JTable(invoicesTableModel);
        this.setBorder(BorderFactory.createTitledBorder(
                BorderFactory.createEtchedBorder(), "Invoices Table", TitledBorder.LEFT,
                TitledBorder.TOP));
        add(new JScrollPane(invoicesTable));
    }

    public void addRows(ArrayList readInvoiceHeader) {
        System.out.println(readInvoiceHeader.size());
        invoicesTableModel.setRowCount(0);

        for (int i = 0; i < readInvoiceHeader.size(); i++) {
            int invoiceNumber = readInvoiceHeader.get(i).getInvoiceNumber();
            String invoiceDate = readInvoiceHeader.get(i).getInvoiceDate();
            String invoiceCustomer = readInvoiceHeader.get(i).getCustomerName();
            double invoiceTotal = readInvoiceHeader.get(i).getInvoiceTotal();

            Object[] objs = {invoiceNumber, invoiceDate, invoiceCustomer, invoiceTotal};

            invoicesTableModel.addRow(objs);
        }
        invoicesTable.setModel(invoicesTableModel);
    }
}