This week's book giveaways are in the iOS and Features new in Java 8 forums. We're giving away four copies each of Barcodes with iOS: Bringing together the digital and physical worlds and Core Java for the Impatient and have the authors on-line! See this thread and this one for details.
By reassigning it? This flag is probably meant as a means to switch debugging on and off quickly. It should probably be static and final, making it a constant. The developer then sets it to true when he needs to debug, and back to false when he deploys it.