This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
As Ernest says, we need some more information. What have you tried so far? Does it compile? If not, what are the compiler errors? If it does compile, what happens when you run it? How does this differ from what you expect? You should also include snippets of your code to illustrate what is going on.
When you provide this information, we will be happy to help you.