Functional Programming in Java

Preface

In any field, find the strangest thing and then explore it.

John Archibald Wheeler

You’re in for a treat. One of the most prominent and widely used languages in the world has evolved. Until now Java gave us one set of tools—the object-oriented paradigm—and we did the best we could with it. Now there’s another, more elegant way to solve the common problems we encounter when developing applications. We can now do quite effectively in Java what was previously possible only on the JVM using other languages—this means more power to Java programmers.

I’m thankful to have had the privilege over the past few decades to program with multiple languages: C, C++, Java, C#, F#, Ruby, Groovy, Scala, Clojure, Erlang, JavaScript… When asked which one’s ...