Calculate All Total Amounts By Adding All Rows

table.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
public void valueChanged(ListSelectionEvent e) {
System.out.println("Value changed");
if(Float.parseFloat(table.getModel().getValueAt(table.getSelectedRow(), 4).toString()) != 0.0){
System.out.println(getTotal());
totalAmount.setText(""+getTotal());
}
}
});

This is what I've tried so far. What i want to do is to calculate all Total Amounts by adding all the rows (5th column only),as 5th column has total amount for 1 product, and set the text for a JTextField whenever the 5th column of any row changes its value.But this isn't working my way. I have also tried keyListener to trigger that change at Enter key typed but that also don't work for me.