In the exercise in Chapter 6, you created a class named Purchase. Each Purchase contains an invoice number, amount of sale, amount of sales tax, and several methods. Add get methods for the invoice number and sale amount fields so their values can be used in comparisons. Next, write a program that declares an array of five Purchase objects and prompt a user for their values. Then, in a loop that continues until a user inputs a sentinel value, ask the user whether the Purchase objects should be sorted and displayed in invoice number order or sale amount order. Save the file as SortPurchasesArray.java.

*****************NEED HELP WITH THIS PROBLEM CANNOT FIGURE IT OUT*************************************

************ Starting from scratch. The Chapter 6 assignment was not originally assigned as an assignment to do !!! ******************

****If your wondering what the Ch.6 question was its: Create a class named Purchase. Each Purchase contains an invoice number, amount of sale, and amount of sales tax. Include set methods for the invoice number and sale amount. Within the set() method for the sale amount, calculate the sales tax as 5% of the sale amount. Also include a display method that displays a purchase's details.Save the file as Purchase.java