Polymorphism and Abstract Classes - Absolute Java - page 490

Display 8.1 The Base Class Sale (part 2 of 3)

41 /**
42 Precondition: newPrice is nonnegative.
43 */
44 public void setPrice( double newPrice)
45 {
46 if (newPrice >= 0)
47 price = newPrice;
48 else
49 {
50 System.out.println("Error: Negative price.");
51 System.exit(0);
52 }
53 }

54 public String getName()
55 {
56 return name;

57 }

58 /**
59 Precondition: newName is a nonempty string.
60 */
61 public void setName(String newName)
62 {
63 if (newName != null && newName != "")
64 name = newName;
65 else
66 {
67 System.out.println("Error: Improper name value.");
68 System.exit(0);
69 }
70 }

71 public String toString()
72 {
73 return (name + " Price and total cost = $" + price);

74 }

75 public double bill()
76 {
77 return price;

78 }