Maybe it is an old book, when Swing had not yet evolved.
You should pay close attention to the compiler. The compiler is your friend. Not only does it tell you what the problem is, it also tells you the line number where the problem is. I am sure the compiler told you more than just
cannot find symbol
symbol: variable shippingGroup
location: class CandleApplet
I would recommend paying attention to what the compiler tells you.
Hint: Check your spelling