Softwareentwicklung in C++ - ASC

212 9. Klassen in C++
93 ∗ @return the s t r i n g to be displayed
94 ∗/
95
96 const char ∗ DisplayableObject : : getStringRep ( )
97 {
98 return ( s t r i n g r e p ) ;
99 }
Die Implementation der Klasse PrintableObject ist im Prinzip äquivalent
dazu:
107 PrintableObject : : PrintableObject ( const char ∗ s t r i n g r e p )
108 {
109 i f ( ! s t r i n g r e p )
110 {
111 s t r i n g r e p = 0;
112 return ;
113 }
114 s t r i n g r e p = new char [ s t r l e n ( s t r i n g r e p ) + 1 ] ;
115 strcpy ( s t r i n g r e p , s t r i n g r e p ) ;
116 }
117
118 //−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
119 /∗ d e s t r u c t o r
120 ∗/
121
122 PrintableObject : : ˜ PrintableObject ( )
123 {
124 i f ( s t r i n g r e p )
125 delete [ ] s t r i n g r e p ;
126 }
127
128 //−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
129 /∗
130 ∗ @return the s t r i n g to be displayed
131 ∗/
132
133 const char ∗ PrintableObject : : getStringRep ( )
134 {
135 return ( s t r i n g r e p ) ;
136 }
Zu guter Letzt sieht die Klasse MyObject nach unseren Betrachtungen von
oben folgendermaßen aus:
138 //−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
139 /∗ constructor
140 ∗
141 ∗ @param s t r i n g r e p the s t r i n g r e p r e s e n t a t i o n o f the o b j e c t
142 ∗/
143
144 MyObject : : MyObject ( ) : DisplayableObject ( ” ( disp ) j u s t a s t r i n g rep ” ) ,
145 PrintableObject ( ” ( p r i n t ) j u s t a s t r i n g rep ” )
146
147 {
148 }
149
150 //−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
151 /∗ d e s t r u c t o r
152 ∗/
153