Diaz Eduardo. - Clojure for Java Developers

Eduardo Daz is a developer with a strong background in the Java language. He has a passion for functional programming and new programming paradigms. His work includes full stack development, systems design, and high volume real time data processing.

He has worked on every technology related problem you can imagine, as a consultant solving anything related to Java, UNIX, C, or any other strange problem you might have had.

As a developer, he has been working for around 10 years on Java, Python, Scala, Clojure, in the media, bank, and primarily communications industries.

He is currently working at Grupo Expansion, a media company, where he helps design and implement a new content delivery platform aiming to empower content editors and encourage developers to find new ways to use data.

First of all, I would like to thank Neeshma Ramakrishnan and Kajal Thapar at Packt Publishing, they are the best editors, they have an incredible amount of patience and without them, there would be nothing even close to a book.

I would also like to thank my colleagues and friends at Grupo Expansion, Lucasian Labs, and Javanes; they have helped me grow in every way imaginable. Thanks for everything!

Last but not the least, thanks to my family for always keeping up with me, cheering me up, believing in me and helping in everything I do, even when it means not seeing me for weeks or months. I truly value your support!

Ning Sun is a software engineer currently working for a China-based startup, LeanCloud, providing one-stop "backend as a service" for mobile apps. Being a startup engineer, he has to solve various kinds of problems and play different kinds of roles; however, he has always been an enthusiast for open source technology. He contributes to several open source projects and has also learned a lot from them.

At LeanCloud, he built a messaging system that supports tens of millions of clients per day. The system is fully powered by Clojure and its ecosystem. He has been an early member of Clojure Chinese community since 2011. He has delivered talks at several meetups and has been very active in the mailing list and open source projects. Ning created Clojure RPC library "Slacker", which is widely used at LeanCloud and several other companies.

He worked on https://Delicious.com in 2013, which is known as one of the most important websites in the early Web 2.0 era.

He has been a reviewer of two books about Solr at Packt Publishing. Also, he was the reviewer of Programming Clojure , Chinese edition.

You can always find him on Github.com/sunng87 and Twitter.com/Sunng.

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Preface

In the last few years, we have seen a widespread tendency to create new languages for JVM. There are all sorts of new languages with different paradigms and different ways of working.

Clojure is one of those languages, one that we believe is worth learning.

Over the course of this book, you will learn about Clojure and how opinionated it is. You will learn why immutable objects are not only possible, but it is a good idea to use them.

You will learn about functional programming and see how it fits the concept of immutable programs.

You will understand the very powerful idea of representing your code as a data structure of the same language.

It is important to note that we will build all this knowledge on top of what you already know; this book assumes that you understand the Java language and a bit of how it works. It assumes that you understand how to create classes and objects, how to call methods, and also a bit about the JVM. We will find similarities and differences from the Java language that you already know, so you can understand how the Clojure world works.

It is said that a great programmer is not the one who knows a lot of different programming languages, it is someone who knows different programming paradigms.

Clojure brings ideas from Lisp and functional programming, which are different to what you are used to. This book will help you understand the power behind these ideas and why a language so old still exists and has a place.

Learning Lisp is one of the great pleasures of life, I hope you enjoy it!

What this book covers

, Getting Started with Clojure , is your first step with Clojure, from how to install an interpreter, how to use the IntelliJ plugin Cursive Clojure, and how to start writing your first lines of code in Clojure.