diff options
| author | Sven Eisenhauer <sven@sven-eisenhauer.net> | 2023-11-10 15:11:48 +0100 |
|---|---|---|
| committer | Sven Eisenhauer <sven@sven-eisenhauer.net> | 2023-11-10 15:11:48 +0100 |
| commit | 33613a85afc4b1481367fbe92a17ee59c240250b (patch) | |
| tree | 670b842326116b376b505ec2263878912fca97e2 /Bachelor/Prog1/examples/ch06/Fig06_21_23 | |
| download | Studium-master.tar.gz Studium-master.tar.bz2 | |
Diffstat (limited to 'Bachelor/Prog1/examples/ch06/Fig06_21_23')
| -rw-r--r-- | Bachelor/Prog1/examples/ch06/Fig06_21_23/Fig06_23.cpp | 53 | ||||
| -rw-r--r-- | Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.cpp | 55 | ||||
| -rw-r--r-- | Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.h | 40 |
3 files changed, 148 insertions, 0 deletions
diff --git a/Bachelor/Prog1/examples/ch06/Fig06_21_23/Fig06_23.cpp b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Fig06_23.cpp new file mode 100644 index 0000000..a5b14b6 --- /dev/null +++ b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Fig06_23.cpp @@ -0,0 +1,53 @@ +// Fig. 6.23: fig06_23.cpp
+// Demonstrating a public member function that
+// returns a reference to a private data member.
+#include <iostream>
+
+using std::cout;
+using std::endl;
+
+// include definition of class Time from time4.h
+#include "time4.h"
+
+int main()
+{
+ Time t;
+
+ // store in hourRef the reference returned by badSetHour
+ int &hourRef = t.badSetHour( 20 );
+
+ cout << "Hour before modification: " << hourRef;
+
+ // use hourRef to set invalid value in Time object t
+ hourRef = 30;
+
+ cout << "\nHour after modification: " << t.getHour();
+
+ // Dangerous: Function call that returns
+ // a reference can be used as an lvalue!
+ t.badSetHour( 12 ) = 74;
+
+ cout << "\n\n*********************************\n"
+ << "POOR PROGRAMMING PRACTICE!!!!!!!!\n"
+ << "badSetHour as an lvalue, Hour: "
+ << t.getHour()
+ << "\n*********************************" << endl;
+
+ return 0;
+
+} // end main
+
+/**************************************************************************
+ * (C) Copyright 1992-2002 by Deitel & Associates, Inc. and Prentice *
+ * Hall. All Rights Reserved. *
+ * *
+ * DISCLAIMER: The authors and publisher of this book have used their *
+ * best efforts in preparing the book. These efforts include the *
+ * development, research, and testing of the theories and programs *
+ * to determine their effectiveness. The authors and publisher make *
+ * no warranty of any kind, expressed or implied, with regard to these *
+ * programs or to the documentation contained in these books. The authors *
+ * and publisher shall not be liable in any event for incidental or *
+ * consequential damages in connection with, or arising out of, the *
+ * furnishing, performance, or use of these programs. *
+ *************************************************************************/
diff --git a/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.cpp b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.cpp new file mode 100644 index 0000000..eef65f2 --- /dev/null +++ b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.cpp @@ -0,0 +1,55 @@ +// Fig. 6.22: time4.cpp
+// Member-function definitions for Time class.
+
+// include definition of class Time from time4.h
+#include "time4.h"
+
+// constructor function to initialize private data;
+// calls member function setTime to set variables;
+// default values are 0 (see class definition)
+Time::Time( int hr, int min, int sec )
+{
+ setTime( hr, min, sec );
+
+} // end Time constructor
+
+// set values of hour, minute and second
+void Time::setTime( int h, int m, int s )
+{
+ hour = ( h >= 0 && h < 24 ) ? h : 0;
+ minute = ( m >= 0 && m < 60 ) ? m : 0;
+ second = ( s >= 0 && s < 60 ) ? s : 0;
+
+} // end function setTime
+
+// return hour value
+int Time::getHour()
+{
+ return hour;
+
+} // end function getHour
+
+// POOR PROGRAMMING PRACTICE:
+// Returning a reference to a private data member.
+int &Time::badSetHour( int hh )
+{
+ hour = ( hh >= 0 && hh < 24 ) ? hh : 0;
+
+ return hour; // DANGEROUS reference return
+
+} // end function badSetHour
+
+/**************************************************************************
+ * (C) Copyright 1992-2002 by Deitel & Associates, Inc. and Prentice *
+ * Hall. All Rights Reserved. *
+ * *
+ * DISCLAIMER: The authors and publisher of this book have used their *
+ * best efforts in preparing the book. These efforts include the *
+ * development, research, and testing of the theories and programs *
+ * to determine their effectiveness. The authors and publisher make *
+ * no warranty of any kind, expressed or implied, with regard to these *
+ * programs or to the documentation contained in these books. The authors *
+ * and publisher shall not be liable in any event for incidental or *
+ * consequential damages in connection with, or arising out of, the *
+ * furnishing, performance, or use of these programs. *
+ *************************************************************************/
diff --git a/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.h b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.h new file mode 100644 index 0000000..92a5d84 --- /dev/null +++ b/Bachelor/Prog1/examples/ch06/Fig06_21_23/Time4.h @@ -0,0 +1,40 @@ +// Fig. 6.21: time4.h
+// Declaration of class Time.
+// Member functions defined in time4.cpp
+
+// prevent multiple inclusions of header file
+#ifndef TIME4_H
+#define TIME4_H
+
+class Time {
+
+public:
+ Time( int = 0, int = 0, int = 0 );
+ void setTime( int, int, int );
+ int getHour();
+
+ int &badSetHour( int ); // DANGEROUS reference return
+
+private:
+ int hour;
+ int minute;
+ int second;
+
+}; // end class Time
+
+#endif
+
+/**************************************************************************
+ * (C) Copyright 1992-2002 by Deitel & Associates, Inc. and Prentice *
+ * Hall. All Rights Reserved. *
+ * *
+ * DISCLAIMER: The authors and publisher of this book have used their *
+ * best efforts in preparing the book. These efforts include the *
+ * development, research, and testing of the theories and programs *
+ * to determine their effectiveness. The authors and publisher make *
+ * no warranty of any kind, expressed or implied, with regard to these *
+ * programs or to the documentation contained in these books. The authors *
+ * and publisher shall not be liable in any event for incidental or *
+ * consequential damages in connection with, or arising out of, the *
+ * furnishing, performance, or use of these programs. *
+ *************************************************************************/
|