Minor Description
As discussed in this Stack Overflow question, the documentation for CharSet.getInstance() don't explain clearly how to include the negation character (^) as a literal character.
The two solutions suggested in the SO question are:
// Add the '^' on its own CharSet.getInstance("^", "otherlettershere"); // Add the '^' as the last character CharSet.getInstance("otherlettershere^")
If those are the best options, we should add a line to the Javadoc to indicate this. If there is a better way, clearly that should be documented instead.