How to Pass a Clojure Function as java.util.Function

What are the steps to pass a Clojure function as a java.util.Function?

(defn my-clojure-function [x]
  (+ x 1))

Passing a Clojure function as a `java.util.Function` allows you to leverage Java's functional interfaces. This can be useful when integrating Clojure with Java libraries that expect a `java.util.Function`.

(import '[java.util.function Function])

(defn clojure-to-java-function [clj-fn]
  (reify Function
    (apply [_ x]
      (clj-fn x))))

Causes

• Lack of understanding of how Clojure's function types interact with Java's functional interfaces.
• Not using the correct adapter to wrap the Clojure function.

Solutions

• Utilize the `clojure.core/fn` to create a Clojure function.
• Use the `reify` construct or existing interop functions to implement `java.util.Function`.

Mistake: Trying to use a Clojure function directly without adapting it for Java.

Solution: Wrap the Clojure function with an adapter that conforms to `java.util.Function`.

Mistake: Overlooking the incompatible types between Clojure and Java arguments or return types.

Solution: Ensure the function signatures match the expected Java types.