Big Java & Java Concepts example project "permute"

You can use this project as follows:

 - invoke the main method of the driver class PermutationGenerator by 
 right-clicking on the class representation and selecting the main method.
 - individually create PermutationGenerator objects and inspect their internal state for permutations
 
This project illustrates concepts covered in Big Java & Java Concepts, Chapter 18 
"Recursion".

 - to learn about the method of recursion
 - to understand the relationship between recursion and iteration
 - to analysis problems that are much easier to solve by recursion than by iteration
 - to learn to think recursively
 - to be able to use recursive helper methods
 - to understand when the use of recursion affects the efficiency of an algorithm