I'm trying to use a try/catch statement inside an inner class of an actionlistener but it does not catch the exceptions even when I deliberately trigger them. Here is the code excerpt:

```
btnPerformCalculation.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent ae) {

        double runtime = Math.abs(Double.parseDouble(txtRunTime.getText()));
        double downtime = Math.abs(Double.parseDouble(txtDownTime.getText()));
        double blockedtime = Math.abs(Double.parseDouble(txtBlockedTime.getText()));
        double lineefficiency = 100 * runtime / (runtime + downtime + blockedtime);

        try {
            txtEfficiencyAnswer.setText(String.format("%.2f", lineefficiency));
        } catch (Exception e) {
            JOptionPane.showMessageDialog(frame, "Error:" + e.getMessage());
            txtRunTime.setText("0");
            txtDownTime.setText("0");
            txtBlockedTime.setText("0");
        }
    }
});

```