Java to Kotlin: A Refactoring Guidebook

“The fastest way to upgrade your skills from Java to Kotlin. Essential reading for any professional Java developer.” —Dawn Griffiths & David Griffiths, Authors of Head First Kotlin

“Nat and Duncan open the book by saying they wish this book had existed when they adopted Kotlin. I completely agree. The book takes their experiences, their trials and errors, and helps you, the reader, to be on the right path. It definitely is a book that should be on anyone’s shelf coming to Kotlin from the JVM ecosystem. An enjoyable read, and an even better reference guide!” —Hadi Hariri, JetBrains Developer Advocate and Host of the Talking Kotlin Podcast.

“To take familiar good old Java code and see it transform, incrementally, into concise, clear, expressive and easy to maintain Kotlin code is a wonderful way to learn the language. Benefit from the experience McGregor and Pryce have distilled in this book.” —Dr. Venkat Subramaniam, Award-Winning Author and Founder of Agile Developer, Inc

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We’ve gone to print! Actual books are available from Amazon UK, Amazon US, Barnes and Noble, Waterstones, Foyles, and other reputable sellers.

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or access online on the O’Reilly platform.

Other Resources

The authors hang out on the Kotlin language Slack. You can find them in the #java-to-kotlin-refactoring channel.

Duncan has written about the tools used to write the book on his blog.

We’ve been interviewed for the Talking Kotlin podcast - you can watch it on YouTube.

Also on YouTube, a series converting the Gilded Rose Kata from Java to Kotlin.