Java 9 and its new features add to the richness of the language--one of the most-used languages to build robust software applications. Java 9 comes with a special emphasis on modularity, implemented from Project Jigsaw. This book is your one-stop guide to mastering the changes made to the Java platform. The book gives an overview and explanation of the new features introduced in Java 9 and the importance of the new APIs and enhancements. Some of the new features of Java 9 are groundbreaking, and if you are an experienced programmer, you will be able to make your enterprise application leaner by implementing these new features. You will be provided with practical guidance in applying the newly acquired knowledge in regards to Java 9 and further information on future developments of the Java platform. This book will improve your productivity, making your applications faster. By learning the best practices in Java, you will become the go-to person in your organization for Java 9. By the end of this book, you will not only know the important concepts of Java 9 but you will also have a nuanced understanding of the important aspects of programming with this great language.
Chapter 1, The Java 9 Landscape, explores the most significant features introduced in Java 9, including Project Jigsaw, the Java Shell, G1 garbage collection, and reactive programming. This chapter provides introductions to these topics, priming them for deeper coverage in the subsequent chapters.
Chapter 2, Discovering Java 9, covers several changes to the Java platform to include heap space efficiencies, memory allocation, compilation process improvements, type testing, annotations, automated runtime compiler tests, and improved garbage collection.
Chapter 3, Java 9 Language Enhancements, focuses on the changes made to the Java language. These changes impact variable handlers, depreciation warnings, improvements on Project Coin changes implemented in Java 7, and import statement processing.
Chapter 4, Building Modular Applications with Java 9, examines the structure of a Java module as specified by Project Jigsaw and how Project Jigsaw was implemented as part of the Java platform. This chapter also reviews the key internal changes to the Java platform as they relate to the new modular system.
Chapter 5, Migrating Applications to Java 9, explores how to migrate Java 8 applications to the Java 9 platform. Both manual and semi-automated migration processes are covered.
Chapter 6, Experimenting with the Java Shell, covers JShell, the new command-line read-eval-print loop tool in Java 9. Coverage includes information regarding the tool, the read-eval-print loop concept, and the commands and command-line options for use with JShell.
Chapter 7, Leveraging the New Default G1 Garbage Collector, takes an in-depth look at garbage collection and how it is handled in Java 9.
Chapter 8, Microbenchmarking Applications with JMH, examines how to write performance tests using the Java Microbenchmark Harness (JMH), a Java harness library for writing benchmarks for the Java Virtual Machine (JVM). Maven is used along with JMH to help illustrate the power of microbenchmarking with the new Java 9 platform.
Chapter 9, Making Use of the ProcessHandle API, reviews new class APIs that enable the management of operating system processes.
Chapter 10, Fine-Grained Stack Tracing, covers the new API that permits an effective means of stack walking. The chapter includes detailed information on how to access stack trace information.
Chapter 11, New Tools and Tool Enhancements, covers 16 Java Enhancement Proposals (JEPs) that were incorporated into the Java 9 platform. These JEPs cover a wide range of tools and updates to APIs to make development with Java easier with greater optimization possibilities for our Java applications.
Chapter 12, Concurrency Enhancements, covers concurrency enhancements introduced with the Java 9 platform. The primary focus is the support for reactive programming, a concurrency enhancement that is provided by the Flow class API. Additional concurrency enhancements introduced in Java 9 are also covered.
Chapter 13, Security Enhancements, covers several small changes made to the JDK that involve security. The security enhancements introduced with the Java 9 platform provide developers with a greater ability to write and maintain applications that are more secure than previously possible.
Chapter 14, Command-Line Flags, explores the command-line flag changes in Java 9. Concepts covered in this chapter include unified JVM logging, compiler control, diagnostic commands, heap-profiling agent, JHAT, command-line flag argument validation, and compiling for older platform versions.
Chapter 15, Best Practices in Java 9, focuses on working with utilities provided by the Java 9 platform to include UTF-8 property files, Unicode 7.0.0, Linux/AArch64 port, multiresolution images, and common locale data repository.
Chapter 16, Future Directions, provides an overview of the future developments of the Java platform, beyond Java 9. This includes a specific look at what is planned for Java 10 and what further changes we are likely to see in the future.
To work with this text, you will need at least a basic knowledge of the Java programming language.
You will also need the following software components:
- Java SE Development Kit 9 (JDK)
- An Integrated Development Environment (IDE) for coding. Here are suggestions:
- Eclipse
- IntelliJ
- NetBeans
This book is for enterprise developers and existing Java developers. Basic knowledge of Java is necessary.
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