Java to Kotlin: A Refactoring Guidebook

Praise for Java to Kotlin on O’Reilly

⭐️⭐️⭐️⭐️⭐️

Extremely well written. Gives historical context as to why Kotlin is what it is and how that fixes issues that were accumulated in the Java througout the years. A great intro on how to start with Java to Kotlin conversion on your projects. —josef.bodnar, October 19, 2021

⭐️⭐️⭐️⭐️⭐️

—aldr, July 7, 2021

⭐️⭐️⭐️⭐️⭐️

I have been using Java for over 10 years, this book is a “breakthrough” for me, it not only helped me develop a “functional thing” when approaching a new problem, it also helped guiding me in migrating existing code (if we want to) in a safe and progressive manner through refactoring and tooling. It was a very enjoyable read, I have to admit that after 10 years of Java/OO/updating mutable state, to step into this next level, I need to (and I am willing to) completely “rewire” my brain to a more functional settings. I know where my currently gap is and what my future approach might look like, and I am convinced that the continued learning and practicing will lead to better (more concise, reasonable, composable, immutable) software. Great thanks to Duncan and Nat.

—rockyu, July 7, 2021

⭐️⭐️⭐️⭐️⭐️

Even if you don’t write Java this book is invaluable. Much of it can be applied to Swift or even Javascript —smithjn, May 23, 2021

⭐️⭐️⭐️⭐️⭐️

—safarileandrozis, May 15, 2021