Declaration :

• Uml : + what() : const char*
• C++ : public: virtual const char* what () const

Declaration :

• Uml : + rootCause() : std::exception
• C++ : public: std::exception rootCause ()

If this exception was caused by a chain of further exceptions,
return the first one registered in this throw sequence.
This works only, if every exceptions thrown as a consequence
of another exception is propperly constructed by passing
the original exception to the constructor

Declaration :

• Uml : - cause : std::exception
• C++ : private: std::exception cause

a copy of the first exception encountered in this exception chain