stoy tratando de escribir números arábigos en unJTextField y uséDocumentListener como sigue

txtName.getDocument().addDocumentListener(this);

...

public void insertUpdate(DocumentEvent e){setLabel();}
public void removeUpdate(DocumentEvent e){setLabel();}
public void changedUpdate(DocumentEvent e){}

public void setLabel()
{
    String s = txtName.getText();

    s = s.replace('0','\u0660');
    s = s.replace('1','\u0661');
    s = s.replace('2','\u0662');
    s = s.replace('3','\u0663');
    s = s.replace('4','\u0664');
    s = s.replace('5','\u0665');
    s = s.replace('6','\u0666');
    s = s.replace('7','\u0667');
    s = s.replace('8','\u0668');
    s = s.replace('9','\u0669');
    s = s.replace('.',',');

    txtName.setText(s);
}

pero recibí un error entxtName.setText(s);

y el error fue:

Exception occurred during event dispatching:
java.lang.IllegalStateException: Attempt to mutate in notification