Design and implement a program that creates an exception class
called , designed to be thrown
when an improper designation for a document is encountered
during processing. suppose in a particular business all documents
are given a two-character designation starting with either u, c,
or p, standing for unclassified, confidential, or proprietary. if a
document designation is encountered that doesn’t fit that description,
the exception is thrown. create a driver program to test the
exception, allowing it to terminate the program.