Section 3 java class design Oracle Java Programming

Sesction 3 java class design

                (Answer all questions in this section)

1.            An interface and abstract class are different names for the same type of class structure. True or false?     Mark for Review

                True

                False (*)

2.            Modeling classes for a business problem requires understanding the business not Java. True or false?       Mark for Review

(1) Points

                True

                False (*)

3.            An immutable class can be subclassed in which of these scenarios? 

                The class has public static methods. (*)

                The class has default instance methods.

                The final class doesn't have any methods.

                The class has protected instance methods.

                None of the above.

4.            An immutable method is final. True or false?       Mark for Review

                True (*)

                False

5.            Default access methods have no specifier in their definition or implementation. True or false?     Mark for Review

                True (*)

                False

6.            Public access methods can't be subclassed. True or false?              Mark for Review

(1) Points

                True

                False (*)

7.            The instanceof operator is a boolean comparison operator. True or false?              Mark for Review

(1) Points

                True (*)

                False

8.            The instanceof operator enables a method to discover the type of object it was invoked upon. True or false?                Mark for Review

(1) Points

                True (*)

                False

9.            Virtual method invocation must be defined with the instanceof operator. True or false?  Mark for Review

                True

                False (*)

10.          Java provides virtual method invocation as a feature and it doesn't require specialized coding. True or false?                Mark for Review

                True (*)

                False

11.          You can't downcast an object explicitly because you must use virtual method invocation. True or false?   Mark for Review

                True

                False (*)

12.          You can always upcast a subclass to an interface provided you don't need to call any methods of the concrete class. True or false?         Mark for Review

                True (*)

                False