From 69dbd9ac479017ae672e0c5bec06ad1e46b73cc2 Mon Sep 17 00:00:00 2001
From: Gary Gregory <garydgregory@gmail.com>
Date: Fri, 27 Mar 2026 14:41:14 -0400
Subject: [PATCH] [COLLECTIONS-888] PatriciaTrie incompatible with Java 21 (JEP
 431 Sequenced Collections)

---
 .../trie/AbstractPatriciaTrie.java            | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/src/main/java/org/apache/commons/collections4/trie/AbstractPatriciaTrie.java b/src/main/java/org/apache/commons/collections4/trie/AbstractPatriciaTrie.java
index 472bbe17d4..4de933dc92 100644
--- a/src/main/java/org/apache/commons/collections4/trie/AbstractPatriciaTrie.java
+++ b/src/main/java/org/apache/commons/collections4/trie/AbstractPatriciaTrie.java
@@ -1432,10 +1432,13 @@ public Set<Map.Entry<K, V>> entrySet() {
     /**
      * Returns the first entry the {@link org.apache.commons.collections4.Trie} is storing.
      * <p>
-     * This is implemented by going always to the left until
-     * we encounter a valid uplink. That uplink is the first key.
+     * This is implemented by going always to the left until we encounter a valid uplink. That uplink is the first key.
+     * </p>
+     *
+     * @return the first entry the {@link org.apache.commons.collections4.Trie} is storing.
+     * @since 4.6.0
      */
-    TrieEntry<K, V> firstEntry() {
+    public TrieEntry<K, V> firstEntry() {
         // if Trie is empty, no first node.
         if (isEmpty()) {
             return null;
@@ -1715,10 +1718,14 @@ public Set<K> keySet() {
     /**
      * Returns the last entry the {@link org.apache.commons.collections4.Trie} is storing.
      *
-     * <p>This is implemented by going always to the right until
-     * we encounter a valid uplink. That uplink is the last key.
+     * <p>
+     * This is implemented by going always to the right until we encounter a valid uplink. That uplink is the last key.
+     * </p>
+     *
+     * @return the last entry the {@link org.apache.commons.collections4.Trie} is storing.
+     * @since 4.6.0
      */
-    TrieEntry<K, V> lastEntry() {
+    public TrieEntry<K, V> lastEntry() {
         return followRight(root.left);
     }