Like all previous editions of this book, this edition continues to be addressed to serious programmers who would like to use Java to develop real projects. The author of this book imagines you, dear reader, as a competent specialist with solid experience in programming in languages other than Java, and hopes that you do not like books that are full of toy examples like programs for controlling toasters or animals in a zoo or "jumping text" . You won't find anything like that in this book. The author's goal is to help you understand the Java language and its libraries fully, and not to create the illusion of such understanding. In this book you will find a lot of code examples that demonstrate almost all of the language and library features discussed. These examples are intentionally kept as simple as possible to focus on the main points. However, for the most part, they are not toys at all, do not cut any sharp corners, and can serve as a good starting point for you to develop your own code.