created March 13, 2009
1. Better encapsulation
of the Goods
class would call
making instance variables private
and using getter and setter methods
to access them.
A further refinement would be to make the class
abstract
and to define additional child classes.
Here is a revised Goods
class:
public abstract class GoodsSGA { private String description; private double price; private int quantity; public GoodsSGA( String des, double pr, int quant ) { description = des; price = pr; quantity = quant; } double getPrice() { return price; } void setPrice( double newPrice) { price = newPrice; } int getQuantity() { return quantity; } void setQuantity ( int newQuantity ) { quantity = newQuantity; } public String toString() { return "item: " + description + " quantity: " + quantity + " price: " + price ; } }
Revise the source code for the classes Food
, Toy
, and Book
.
(Perhaps call the revised classes FoodSG
, ToySG
, and BookSG
.)
create a new class ToiletrySG
for things like bubble bath.
Create a new testing class, StoreSG
to test your revised classes.
Note: the child classes will need to use the getter and setter methods
to access the instance variables that are declared
as private
in GoodsSG
.
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