Not just about JVM params, the book covers application and algorithm issues, database connectivity, as well as JVM issues such as garbage collection algorithms. What is useful, and sadly rare, is that this book not only tells you things you can do, it also tells you things that you can skip, since not every thing you do has a good cost/ benefit payoff.
With an emphasis on standard tools, including open source and those that come with the JDK, you can apply what you learned immediately. The book does not cover every tool, and may not include your favorite, but the discussion has enough tools to get you started.
This book will be useful for both those new to programming in Java (since performance and resource use area rarely emphasized who you are learning to program) and those who have been programming a while but have not spent as much time thinking about performance as one might like.
I got my copy of this book through the Amazon Vine program.