I have possible Errata with the following questions from the LearnKey Master exam on the CD:
Q47 - The reference information is correct, but the "correct answers" are set up as those which
will compile, instead of those which
will not -- so this question is always scored incorrectly.
Q56 - "C" and "D" are both listed as correct answers, but I think "D" is incorrect. If "rate" has a value of zero, then the equals method will be less precise than the hashCode method.
Q35 - This question asks "Which results are NOT possible?", and one of the correct answers listed is "An error occurs at runtime." How is it ever possible to exclude the possibility of a run-time error (ie. hardware failure, operator kills the process, etc.)?
Q57 - The reference information correctly shows "C" as the answer, but the question is always scored incorrectly showing "A" as the answer.
Q53 - The answer lists "is-a relationships always rely on polymorphism" as a true statement. I had always thought that "is-a relationships
can use
polymorphism, but it's also possible to use encapsulation and inheritance without dynamic binding". In Chapter 2, in the two-minute drill under polymorphism (the last bullet on page 153) it states: "Polymorphic method invocations apply only to overridden
instance methods." I know, instance is italicized, but can't you also read the statement straight-up? If I have a sub-class with no methods, where is the polymorphism?
[ June 24, 2006: Message edited by: Rick Dakota ]