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.
You should know that using classes inside any package that starts with sun, sunw or com.sun is discouraged as they can change or even disappear without any notice, and your program may be broken if that occurs. For instance, I've seen one program that only works for Java 1.4.2_08. Even Java 1.4.2_10 broke the program because it could not find such a class.