a. Write a method heading for each method. b. Write preconditions and postconditions for each method. c. Write some Java statements that test the class. d. Implement the dass. e. List any additional...

Extracted text: a. Write a method heading for each method. b. Write preconditions and postconditions for each method. c. Write some Java statements that test the class. d. Implement the dass. e. List any additional methods and attributes needed in the implementa- tion that were not listed in the original design. List any other changes made to the original design. f. Write a program using the class you wrote for Part d that will be used to record sales for a concert. Your program should record phone sales, then sales at the venue. As tickets are sold, the number of seats remain- ing should be displayed. At the end of the program, display the number of tickets sold and the total sales amount for the concert.


Extracted text: Consider a class ConcertPromoter that records the tickets sold for a perfor- mance. Before the day of the concert, tickets are sold only over the phone. Sales on the day of the performance are made only in person at the concert venue. The class has the following attributes: • The name of the band • The capacity of the venue The number of tickets sold • The price of a ticket sold by phone • The price of a ticket sold at the concert venue • The total sales amount It has methods to • Record the sale of one or more tickets • Change from phone sales to sales at the concert venue • Return the number of tickets sold Return the number of tickets remaining • Return the total sales for the concert