From 96ee102e198fbac5b55a3d1d9fa09fd28b2e8910 Mon Sep 17 00:00:00 2001
From: Tobias Ibounig <tobias.ibounig@dynatrace.com>
Date: Fri, 12 Jun 2026 11:53:35 +0200
Subject: [PATCH] perf: skip iterating over empty list

Signed-off-by: Tobias Ibounig <tobias.ibounig@dynatrace.com>
---
 .../java/dev/openfeature/sdk/HookSupport.java |  3 ++
 .../dev/openfeature/sdk/HookSupportTest.java  | 32 +++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/src/main/java/dev/openfeature/sdk/HookSupport.java b/src/main/java/dev/openfeature/sdk/HookSupport.java
index e936fdeda..0891134b3 100644
--- a/src/main/java/dev/openfeature/sdk/HookSupport.java
+++ b/src/main/java/dev/openfeature/sdk/HookSupport.java
@@ -45,6 +45,9 @@ public void setHooks(
 
     private static void addFilteredHooks(
             List<Pair<Hook, HookContext>> dest, Collection<Hook> source, FlagValueType type) {
+        if (source.isEmpty()) {
+            return;
+        }
         for (Hook hook : source) {
             if (hook.supportsFlagValueType(type)) {
                 dest.add(Pair.of(hook, null));
diff --git a/src/test/java/dev/openfeature/sdk/HookSupportTest.java b/src/test/java/dev/openfeature/sdk/HookSupportTest.java
index f7583321a..8d60122d3 100644
--- a/src/test/java/dev/openfeature/sdk/HookSupportTest.java
+++ b/src/test/java/dev/openfeature/sdk/HookSupportTest.java
@@ -14,6 +14,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.concurrent.ConcurrentLinkedQueue;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -161,6 +162,37 @@ void shouldOrderHooksBySource() {
                 .containsExactly(providerHook, optionHook, clientHook, apiHook);
     }
 
+    @Test
+    @DisplayName("empty ConcurrentLinkedQueue sources produce no hooks")
+    void emptyQueueSourcesProduceNoHooks() {
+        var hookSupportData = new HookSupportData();
+        hookSupport.setHooks(
+                hookSupportData,
+                new ConcurrentLinkedQueue<>(),
+                new ConcurrentLinkedQueue<>(),
+                new ConcurrentLinkedQueue<>(),
+                new ConcurrentLinkedQueue<>(),
+                FlagValueType.STRING);
+        assertThat(hookSupportData.getHooks()).isEmpty();
+    }
+
+    @Test
+    @DisplayName("non-empty ConcurrentLinkedQueue source is not skipped")
+    void nonEmptyQueueSourceIsNotSkipped() {
+        Hook<?> hook = mockGenericHook();
+        var queue = new ConcurrentLinkedQueue<Hook>();
+        queue.add(hook);
+        var hookSupportData = new HookSupportData();
+        hookSupport.setHooks(
+                hookSupportData,
+                new ConcurrentLinkedQueue<>(),
+                new ConcurrentLinkedQueue<>(),
+                queue,
+                new ConcurrentLinkedQueue<>(),
+                FlagValueType.STRING);
+        assertThat(hookSupportData.getHooks()).extracting(Pair::getKey).containsExactly(hook);
+    }
+
     @Test
     void hookThatReturnsTheGivenContext_doesNotResultInAStackOverflow() {
         var hookSupportData = new HookSupportData();