Mock Exam Answers
The following are answers to the questions in the mock exam in Appendix A.
Question 1 (7.1. Implement inheritance)
The keyword extends can be used
A. to create a subclass from another class
B. to create a subinterface from another interface
C. to make a class implement an interface
D. to make an interface implement another interface
Answer: A, B.
The keyword extends can be used to create a child class from another class or a subinterface from another interface. C is incorrect because extends cannot be used to make a class implement an interface. For this, you use the keyword implements. Also in Java an interface cannot implement another interface, so D is incorrect.
Question 2 (6.4. Differentiate between default ...