Sams Teach Yourself C++ in 21 Days

Answers 869

D

9: char* GetString() { return itsString; }

10: private:

11: char* itsString;

12: };

13:

14: OutOfMemory::OutOfMemory(char * theType)

15: {

16: itsString = new char[80];

17: char warning[] = “Out Of Memory! Can’t allocate room for: “;

18: strncpy(itsString,warning,60);

19: strncat(itsString,theType,19);

20: }

21:

22: int main()

23: {

24: try

25: {

26: int *myInt = new int;

27: if (myInt == 0)

28: throw OutOfMemory(“int”);

29: }

30: catch (OutOfMemory& theException)

31: {

32: cout << theException.GetString();

33: }

34: return 0;

35: }

3. The following is one possible answer:
   0: // Exercise 20.3
   1: #include
   2: using namespace std;
   3: // Abstract exception data type
   4: class Exception
   5: {
   6: public:
   7: Exception(){}
   8: virtual ~Exception(){}
   9: virtual void PrintError() = 0;
   10: };
   11:
   12: // Derived class to handle memory problems.
   13: // Note no allocation of memory in this class!
   14: class OutOfMemory : public Exception
   15: {
   16: public:
   17: OutOfMemory(){}
   18: ~OutOfMemory(){}
   19: virtual void PrintError();
   20: private:
   21: };

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