Book Image

Introduction to JVM Languages

Book Image

Introduction to JVM Languages

Overview of this book

Anyone who knows software development knows about the Java Virtual Machine. The Java Virtual Machine is responsible for interpreting Java byte code and translating it into actions. In the beginning, Java was the only programming language used for the JVM. But increasing complexity of the language and the remarkable performance of the JVM created an opening for a new generation of programming languages. If you want to build a strong foundation with the Java Virtual Machine and get started with popular modern programming languages, then this book is for you. The book will begin with a general introduction of the JVM and its features, which are common to the JVM languages, helping you get abreast with its concepts. It will then dive into explaining languages such as Java, Scala, Clojure, Kotlin, and Groovy and will show how to work with each language, their features, use cases, and pros and cons. By writing example projects in those languages and focusing on each language’s strong points, it will help you find the programming language that is most appropriate for your particular needs. By the end of the book, you will have written multiple programs that run on the Java Virtual Machine and know about the differences between the various languages.
Table of Contents (21 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Groovy Development Kit (GDK)


Groovy comes with a large library of classes that can be used to make the life of a developer easier. Some offer new features; the others are wrappers around existing Java Class Library classes to make them easier to use or enhance their functionalities. In this section, we will be looking at some important classes and types of Groovy's runtime library, sometimes called the Groovy Development Kit (GDK), which is installed as part of your Groovy installation.

Groovy Strings (GStrings)

Groovy offers its own variant of the java.lang.String class: groovy.lang.GString. Whenever you create a string with double quotes, Groovy looks whether a feature of GString is used. If that's the case, then it creates a GString; otherwise, it creates an ordinary java.lang.String instance:

    def s = "this is an ordinary java.lang.String instance";

The preceding string does not make use of Groovy features, so Groovy creates a normal java.lang.String. One of the most useful features of...