This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Or it could mean that the process executing this code does not have permissions to access the file. Web servers (and servlet containers) often run with reduced permissions in order to prevent them from doing harm in case they're compromised.