A mix of checked and unchecked exceptions is “effective,” but checked exceptions should only be used for “recoverable conditions” and should not be used “unnecessarily.” ...

Use unchecked exceptions: By using checked exceptions, clients are forced to take a position on errors they can rarely handle. Unchecked exceptions leave the client with a choice.

I know we've had many fine threads on exceptions in Java. Hopefully this particular question hasn't been discussed to death. I solved Problem 11 on Project Euler today. It requires you to do a ...