i was reading SCJP6 and just came around a sentence "By the way if we misused raison d'^etre earlier ,dont send an e mail we'd like to see you work into a programming certification books"-- what does this sentence mean
i don't have the book with me...but i think the authors are trying to be humorous here. apparently, they use the phrase 'raison d'^etre' at some point. People (i.e. the general public) likes to point out mistakes authors make.
The authors here are saying "Yes, we KNOW we may not have used that phrase correctly, but we don't care. It's a hard phrase to use at all, let alone in a book on programming. If you think YOU can do a better job using it in a technical book, write your own book, and don't bug us about it".
Whether they succeeded at being humorous is up to the reader to decide.
There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors