4 files changed, 169 insertions, 0 deletions
diff --git a/Bachelor/Prog1/examples/ch07/Fig07_20_23/fig07_23.cpp b/Bachelor/Prog1/examples/ch07/Fig07_20_23/fig07_23.cpp
new file mode 100644
index 0000000..a11a543
--- /dev/null
+++ b/Bachelor/Prog1/examples/ch07/Fig07_20_23/fig07_23.cpp
@@ -0,0 +1,39 @@
+// Fig. 7.23: fig07_23.cpp
+// Hiding a class’s private data with a proxy class.
+#include <iostream>
+
+using std::cout;
+using std::endl;
+
+#include "interface.h"  // Interface class definition
+
+int main()
+{
+   Interface i( 5 );
+ 
+   cout << "Interface contains: " << i.getValue() 
+        << " before setValue" << endl;
+
+   i.setValue( 10 );
+
+   cout << "Interface contains: " << i.getValue() 
+        << " after setValue" << endl;
+
+   return 0;
+
+} // end main
+
+/**************************************************************************
+ * (C) Copyright 1992-2003 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/ch07/Fig07_20_23/implementation.h b/Bachelor/Prog1/examples/ch07/Fig07_20_23/implementation.h
new file mode 100644
index 0000000..1630a50
--- /dev/null
+++ b/Bachelor/Prog1/examples/ch07/Fig07_20_23/implementation.h
@@ -0,0 +1,48 @@
+// Fig. 7.20: implementation.h
+// Header file for class Implementation
+
+class Implementation {
+
+public:
+
+   // constructor
+   Implementation( int v )  
+      : value( v )  // initialize value with v
+   { 
+      // empty body
+
+   } // end constructor Implementation
+
+   // set value to v
+   void setValue( int v )   
+   { 
+      value = v;  // should validate v
+
+   } // end function setValue
+
+   // return value 
+   int getValue() const      
+   { 
+      return value; 
+
+   } // end function getValue
+
+private:
+   int value;
+
+}; // end class Implementation
+
+/**************************************************************************
+ * (C) Copyright 1992-2003 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/ch07/Fig07_20_23/interface.cpp b/Bachelor/Prog1/examples/ch07/Fig07_20_23/interface.cpp
new file mode 100644
index 0000000..0f895fd
--- /dev/null
+++ b/Bachelor/Prog1/examples/ch07/Fig07_20_23/interface.cpp
@@ -0,0 +1,48 @@
+// Fig. 7.22: interface.cpp
+// Definition of class Interface
+#include "interface.h"       // Interface class definition
+#include "implementation.h"  // Implementation class definition
+
+// constructor
+Interface::Interface( int v ) 
+   : ptr ( new Implementation( v ) )  // initialize ptr
+{ 
+   // empty body
+
+} // end Interface constructor
+
+// call Implementation's setValue function
+void Interface::setValue( int v ) 
+{ 
+   ptr->setValue( v ); 
+
+} // end function setValue
+
+// call Implementation's getValue function
+int Interface::getValue() const 
+{ 
+   return ptr->getValue(); 
+
+} // end function getValue
+
+// destructor
+Interface::~Interface() 
+{ 
+   delete ptr; 
+
+} // end ~Interface destructor
+
+/**************************************************************************
+ * (C) Copyright 1992-2003 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/ch07/Fig07_20_23/interface.h b/Bachelor/Prog1/examples/ch07/Fig07_20_23/interface.h
new file mode 100644
index 0000000..5d229e1
--- /dev/null
+++ b/Bachelor/Prog1/examples/ch07/Fig07_20_23/interface.h
@@ -0,0 +1,34 @@
+// Fig. 7.21: interface.h
+// Header file for interface.cpp
+
+class Implementation;     // forward class declaration
+
+class Interface {
+
+public:
+   Interface( int );
+   void setValue( int );  // same public interface as
+   int getValue() const;  // class Implementation
+   ~Interface();
+
+private:
+
+   // requires previous forward declaration (line 4)
+   Implementation *ptr;   
+
+}; // end class Interface
+
+/**************************************************************************
+ * (C) Copyright 1992-2003 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.                     *
+ *************************************************************************/