As a minor advice. Why have you initialized your text fields with so many space characters? If you want the text fields to be empty, the just initialize them like this:
JTextField myTextField=new JTextField("");
Thus the compiler knows that text fields must be empty. And by doing so, you won't be needing trim() method when parsing the value from the text fields.
And also in the actionPerformed() method with getting the name of the event, rather i would just use:
Other than that, the code seems fine.