A comprehensive guide to study the version updates from JDK9.0 to JDK13.0Version release is one of the important phases of success of any programming language. Over the years, Java had made many improvements in its API to make to reliable and flexible to use. This book aims at providing you information related to all the updates from JDK9.0 to JDK13.0 in one place.This book starts with a brief history of Java. It covers how Java has evolved as a complete programming language over the years by launching different versions. You will learn the concept of module system and other important concepts introduced in JSE9 .0 and JSE10.0. Moving ahead, the book will take you through updates in JDK11.0. Concepts like Epsilon, ZGC, and Nest-Based access control have also been discussed.Though the version updates are good to learn, they create complexities in updating the existing code to make it compatible with the new version. This book talks in detail about how you can migrate your legacy code to match up with the new versions. It also covers how to use jshell, a tool used to test your code snippet without writing the complete application class, with numerous examples. Further, this book covers in detail the concept of reactive programming. Concepts like publisher, subscriber, subscription and back-pressure have been discussed with examples.At the end of the book, you will learn about the very recent updates which have been released by Java. The chapters talk about JDK12.0 and JDK13.0. They cover concepts like Shenondaoh, microbenchmark suit, modified switch expression from JDK12.0. Though Java13 is still a hot-plated dish, this book gives you a fair idea about what are the new updates which have been proposed in this version.KEY FEATURES? Learn the journey of Java from its initial days till date.? Learn how to implement modular programming in java9.? Study the updates in different versions of Java from version 9.0 to 13.0.? Understand the need and working of reactive programming.? Learn to migrate the pre-existing Java code to new versions.? Learn how to use jshell to test a new API before using in a project. WHAT WILL YOU LEARNBy the end of this book, you will be able to implement the updates provided in different versions of Java. This book has covered the updates from version 9.0 to 13.0. You will be able to work with the Java Module System. You will be able to test the new API using jshell. Along with this, you will be able to migrate your legacy code to match the recommendations of new versions of Java. WHO THIS BOOK IS FORThis book covers the new version updates in Java. So, prior knowledge of Java is recommended before reading this book. Though we are covering the versions from JSE9.0 onwards, it is not necessary that the reader should be expert in the earlier versions. If you are keen to know the recent developments in Java API, this is the perfect book for you.