I'm assuming
getExtendedPrice() is returning a double, right? double is a primitive value, so it doesn't have an
equals() method. You can use:
However, I'd really suggest getting used to using the assert methods. Why don't you like them? They give you much richer feedback in general - e.g. the framework can tell you "the expected value was 100.0, but the actual value was 99.9" (or something like that). Yes, you could do that yourself, but it's more work.
I also think assertion methods make the
test more obvious and readable, which is really important.