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

Chapter 7. Clojure

Clojure is a language that is rather different from the other languages covered in this book. It is a language largely inspired by the Lisp programming language, which originally dates back to the late 1950s. Lisp stayed relevant by being up to date with both technology and times. Common Lisp and Scheme are arguably the two most popular Lisp dialects in use today. Clojure is a dialect of Lisp, but its design is influenced by both.

Unlike Java and Scala, Clojure is a dynamic language. Variables do not have fixed types and when compiling, no type checking is performed by the compiler. When a variable is passed to a function that is not compatible with the code in the function, an exception will be thrown at runtime. What's also noteworthy is that Clojure is not an object-orientated language (OOP), unlike all the other languages in this book. Clojure still offers interoperability with Java and JVM, as it can create instances of objects. And, as we will soon see, it can also...