We do not care which specific objects are in the queue. Consequently, there are really just four useful values for the variable elements. What are they?

Posted: January 7th, 2022

Use the class BoundedQueue2 for questions a–f below. A

compilable version is available on the book website in the file

BoundedQueue2.java. The queue is managed in the usual

circular fashion.

Suppose we build an FSM where states are defined by the

representation variables of BoundedQueue2. That is, a state is a 4-

tuple defined by the values for [elements, size, front, back]. For

example, the initial state has the value [[null, null], 0, 0, 0], and the

state that results from pushing an object obj onto the queue in its

initial state is [[obj, null], 1, 0, 1].

(a) We do not care which specific objects are in the queue.

Consequently, there are really just four useful values for the

variable elements. What are they?

(b) How many states are there?

(c) How many of these states are reachable ?

(d) Show the reachable states in a drawing.

(e) Add edges for the enQueue() and deQueue() methods. (For

this assignment, ignore the exceptional returns, although you

should observe that when exceptional returns are taken, none of

the instance variables are modified.)

(f) Define a small test set that achieves Edge Coverage. Implement

and execute this test set. You might find it helps to write a

method that shows the internal variables at each call.