You're putting ProfileValue objects into the Vector, and then trying to get the Vector to store them in a String; hence the exception. You have several choices: make the method put just the Strings into the Vector; use ProfileValue instead of String in the toArray() call -- or call toArray() with no arguments to get an Object.
The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - Heraclitus