From eb5a83ab6acec5d577fe840e71c9d3da5494d535 Mon Sep 17 00:00:00 2001
From: James Bodkin <james.bodkin@amphora.net>
Date: Thu, 3 Apr 2025 16:02:36 +0100
Subject: [PATCH] Reduce allocations for empty ArgumentValue

Closes gh-1175

Signed-off-by: James Bodkin <james.bodkin@amphora.net>
[brian.clozel@broadcom.com: apply code conventions]
Signed-off-by: Brian Clozel <brian.clozel@broadcom.com>
---
 .../org/springframework/graphql/data/ArgumentValue.java    | 7 +++++--
 .../springframework/graphql/data/ArgumentValueTests.java   | 1 -
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/spring-graphql/src/main/java/org/springframework/graphql/data/ArgumentValue.java b/spring-graphql/src/main/java/org/springframework/graphql/data/ArgumentValue.java
index 5defd64d..5ce87f2f 100644
--- a/spring-graphql/src/main/java/org/springframework/graphql/data/ArgumentValue.java
+++ b/spring-graphql/src/main/java/org/springframework/graphql/data/ArgumentValue.java
@@ -49,6 +49,8 @@ import org.springframework.util.ObjectUtils;
  */
 public final class ArgumentValue<T> {
 
+	private static final ArgumentValue<?> EMPTY = new ArgumentValue<>(null, false);
+
 	private static final ArgumentValue<?> OMITTED = new ArgumentValue<>(null, true);
 
 
@@ -118,7 +120,7 @@ public final class ArgumentValue<T> {
 
 	@Override
 	public boolean equals(Object other) {
-		// This covers OMITTED constant
+		// This covers EMPTY and OMITTED constant
 		if (this == other) {
 			return true;
 		}
@@ -142,8 +144,9 @@ public final class ArgumentValue<T> {
 	 * @param <T> the type of value
 	 * @param value the value to hold in the instance
 	 */
+	@SuppressWarnings("unchecked")
 	public static <T> ArgumentValue<T> ofNullable(@Nullable T value) {
-		return new ArgumentValue<>(value, false);
+		return (value != null) ? new ArgumentValue<>(value, false) : (ArgumentValue<T>) EMPTY;
 	}
 
 	/**
diff --git a/spring-graphql/src/test/java/org/springframework/graphql/data/ArgumentValueTests.java b/spring-graphql/src/test/java/org/springframework/graphql/data/ArgumentValueTests.java
index 9cba03ec..fdfa4f0a 100644
--- a/spring-graphql/src/test/java/org/springframework/graphql/data/ArgumentValueTests.java
+++ b/spring-graphql/src/test/java/org/springframework/graphql/data/ArgumentValueTests.java
@@ -74,7 +74,6 @@ class ArgumentValueTests {
 	}
 
 	@Test
-
 	void ifPresentShouldSkipWhenOmitted() {
 		AtomicBoolean called = new AtomicBoolean();
 		ArgumentValue.omitted().ifPresent(value -> called.set(true));