Defining Classes I - Java - page 204

Display 4.9 Yet Another Date Class (part 4 of 4)
90 return ( (monthInt >= 1) && (monthInt <= 12) &&
91 (dayInt >= 1) && (dayInt <= 31) &&
92 (yearInt >= 1000) && (yearInt <= 9999) );
93 }
94 private String monthString( int monthNumber)
95 {
96 switch (monthNumber)
97 {
98 case 1:
99 return "January";
100 case 2:
101 return "February";
102 case 3:
103 return "March";
104 case 4:
105 return "April";
106 case 5:
107 return "May";
108 case 6:
109 return "June";
110 case 7:
111 return "July";
112 case 8:
113 return "August";
114 case 9:
115 return "September";
116 case 10:
117 return "October";
118 case 11:
119 return "November";
120 case 12:
121 return "December";
122 default :
123 System.out.println("Fatal Error");
124 System.exit(0);
125 return "Error"; //to keep the compiler happy
126 }
127 }
128 }
The way that a well-designed class definition uses private instance variables and
public accessor and mutator methods to implement the principle of encapsulation is
diagrammed in Display 4.10.