From c5037c97bd1ecbb44cb6ecf8649b5deb521cc7c4 Mon Sep 17 00:00:00 2001
From: Gary Gregory <garydgregory@gmail.com>
Date: Wed, 10 Jul 2024 08:28:07 -0400
Subject: [PATCH] Add back @FunctionalInterface which was in 4.4

---
 src/main/java/org/apache/commons/collections4/Transformer.java | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/main/java/org/apache/commons/collections4/Transformer.java b/src/main/java/org/apache/commons/collections4/Transformer.java
index 5bf3223614..221b95729b 100644
--- a/src/main/java/org/apache/commons/collections4/Transformer.java
+++ b/src/main/java/org/apache/commons/collections4/Transformer.java
@@ -40,6 +40,7 @@
  * @deprecated Use {@link Function}.
  */
 @Deprecated
+@FunctionalInterface
 public interface Transformer<T, R> extends Function<T, R> {
 
     @Override