Yes, it would be helpful. It doesn't cover most of what you need, and is not an appropriate guide for the topics on the exam, but it DOES cover some areas related to performance and memory use, and these topics ARE on the exam. So, it would not hurt to use this book, and I recommend it anyway. But if you are trying to learn MIDP 2.0, and can get only one book, I recommend the one by Jonathon Knudsen (see my other posts on this).
Most importantly, you need the specs!