In this code example, the program must read a file supplied by the user, but the contents and layout of the file system are sensitive. The program accepts a file name as an input argument but fails to prevent any resulting exceptions from being presented to the user. When a requested file is absent, the FileInputStream constructor throws a FileNotFoundException, allowing an attacker to reconstruct the underlying file system by repeatedly passing fictitious path names to the program. Modify the program by logging the exception and then wrapping it in a more general exception before throwing it.

class ExceptionExample { public static void main(String[] args) throws FileNotFoundException { // Linux stores a user's home directory path in // the environment variable $HOME, Windows in %APPDATA% FileInputStream fis = new FileInputStream(System.getenv("APPDATA") + args[0]); } }