diff --git a/src/main/java/org/apache/commons/lang3/text/StrLookup.java b/src/main/java/org/apache/commons/lang3/text/StrLookup.java
index 3d2f1b7b9..fb009e66e 100644
--- a/src/main/java/org/apache/commons/lang3/text/StrLookup.java
+++ b/src/main/java/org/apache/commons/lang3/text/StrLookup.java
@@ -121,6 +121,8 @@ public abstract class StrLookup<V> {
 
     /**
      * Lookup implementation that uses a Map.
+     *
+     * @param <V> the type of mapped values.
      */
     static class MapStrLookup<V> extends StrLookup<V> {