Puzzles in Java is a preliminary tool for beginners in Java to test their skills and get an in-depth knowledge of core Java. This book consists of 299 unique puzzles that will help readers to complete the self-assessment in understanding Java. Answers to puzzles can be identified using the game codes provided in the beginning of the book. This book encourages the readers to execute the puzzles in JDK to identify the results and understand details of the puzzles.