Q129. What is the relationship between an event-listener interface and an event-adapter class?
An event-listener interface defines the methods that must be implemented by an event handler for a particular kind of event. An event adapter provides a default implementation of an event-listener interface.

Q130. What restrictions are placed on the values of each case of a switch statement?
During compilation, the values of each case of a switch statement must evaluate to a value that can be promoted to an int value.

Q131. What modifiers may be used with an interface declaration?
An interface may be declared as public or abstract.

Q132. Is a class a subclass of itself?
A class is a subclass of itself.