This is a very short book and one that is likely to have a relatively small readership, not because it is bad but because most people will need something different. The substance of the book (i.e. excluding the front matter and the index) is 102 pages. Generally there is information on a left hand page and examples on the opposite page. Sometimes both pages are information without any examples. That means that the author effectively attempts to cover Java, including Collections and Maps, Input and Output in about sixty pages. This is a form of minimalism. To be a user of this book you will need to be someone who does not use Java often enough to be instantly familiar with the basic syntax and semantics of the language together with having little need for any of the APIs other than the two mentioned above. If you fit this description this book will be just what you need as a quick reminder. However, if you do not already know, for example, what an inner class is and how to use it this book will be of no help.
Unfortunately most Java programmers, both novice and experienced, need something a good deal more substantial than this. Let me quote the first paragraph of the preface:
This book gives a concise description of the Java 2 programming language, versions 1.3 and 1.4. It is a quick reference for the reader who has already learned (or is learning) Java from a standard textbook and who wants to know the language in more detail . The book presents the entire Java programming language and essential parts of the class libraries: the collection classes and the input-output classes.
Under no stretch of my imagination can I reconcile the claim I have highlighted with the contents of this book. I am very surprised that the computer science editor at MIT let that claim through.