This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
You are looking both the for loops differently. The basic for loop is for boolean (ba) that is declared as array. The enhanced for loop is for Set, because the type of collection(generic<> is not specified here, the things come out from Set is Object.