Data Structures and Algorithms in Java[1].pdf - Fulvio Frisone

any case, a progression requires a way of defining its first value and it needs a
way of identifying the current value as well.
We begin by defining a class, Progression, shown in Code Fragment 2.2,
which defines the standard fields and methods of a numeric progression.
Specifically, it defines the following two long-integer fields:
• first: first value of the progression;
• cur: current value of the progression;
and the following three methods:
firstValue(): Reset the progression to the first value, and return
that value.
value.
nextValue(): Step the progression to the next value and return that
printProgression(n): Reset the progression and print the first n values of
the progression.
We say that the method printProgression has no output in the sense that it
does not return any value, whereas the methods firstValue and nextValue
both return long-integer values. That is, firstValue and nextValue are
functions, and printProgression is a procedure.
The Progression class also includes a method Progression(), which is a
constructor. Recall that constructors set up all the instance variables at the time
an object of this class is created. The Progression class is meant to be a
general superclass from which specialized classes inherit, so this constructor is
code that will be included in the constructors for each class that extends the
Progression class.
Code Fragment 2.2:
class.
General numeric progression
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