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 probably need to implement a KeyListener and listen for that sequence of key strokes. Not sure what you mean when you say that you want to "mask" them. You can "consume" that second event, which will probably do what you intend. Actually getting rid of BOTH would require buffering up key strokes before releasing them to the queue, which is way less straight forward.
"JavaRanch, where the deer and the Certified play" - David O'Meara