Answers to Self Tests - Java: A Beginner's Guide - page 857

It returns true if the invoking thread is still running, and false if it has been termin-
ated.
Chapter 12: Enumerations, Autoboxing, Static Import, and An-
notations
1 . Enumeration constants are said to be self-typed . What does this mean?
In the term self-typed , the “self” refers to the type of the enumeration in which the
constant is defined. Thus, an enumeration constant is an object of the enumeration of
which it is a part.
2 . What class do all enumerations automatically inherit?
The Enum class is automatically inherited by all enumerations.
3 . Given the following enumeration, write a program that uses values( ) to show a list of
the constants and their ordinal values.
The solution is
4 . The traffic light simulation developed in Try This 12-1 can be improved with a few
simple changes that take advantage of an enumeration's class features. In the version
shown, the duration of each color was controlled by the TrafficLightSimulator class
by hard-coding these values into the run( ) method. Change this so that the duration
of each color is stored by the constants in the TrafficLightColor enumeration. To do