From c41478466b65b185ece03038d50742f53e506742 Mon Sep 17 00:00:00 2001
From: Chris Povirk <cpovirk@google.com>
Date: Fri, 9 Jun 2023 06:29:29 -0400
Subject: [PATCH] Annotate the parameter of `List.sort` as `@Nullable`. (#40)

---
 src/java.base/share/classes/java/util/ArrayList.java            | 2 +-
 src/java.base/share/classes/java/util/List.java                 | 2 +-
 src/java.base/share/classes/java/util/Vector.java               | 2 +-
 .../classes/java/util/concurrent/CopyOnWriteArrayList.java      | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/java.base/share/classes/java/util/ArrayList.java b/src/java.base/share/classes/java/util/ArrayList.java
index 14aca859e0c..fa750301acd 100644
--- a/src/java.base/share/classes/java/util/ArrayList.java
+++ b/src/java.base/share/classes/java/util/ArrayList.java
@@ -1753,7 +1753,7 @@ private void replaceAllRange(UnaryOperator<E> operator, int i, int end) {
 
     @Override
     @SuppressWarnings("unchecked")
-    public void sort(Comparator<? super E> c) {
+    public void sort(@Nullable Comparator<? super E> c) {
         final int expectedModCount = modCount;
         Arrays.sort((E[]) elementData, 0, size, c);
         if (modCount != expectedModCount)
diff --git a/src/java.base/share/classes/java/util/List.java b/src/java.base/share/classes/java/util/List.java
index e414723de35..a70e0d14112 100644
--- a/src/java.base/share/classes/java/util/List.java
+++ b/src/java.base/share/classes/java/util/List.java
@@ -529,7 +529,7 @@ default void replaceAll(UnaryOperator<E> operator) {
      * @since 1.8
      */
     @SuppressWarnings({"unchecked", "rawtypes"})
-    default void sort(Comparator<? super E> c) {
+    default void sort(@Nullable Comparator<? super E> c) {
         Object[] a = this.toArray();
         Arrays.sort(a, (Comparator) c);
         ListIterator<E> i = this.listIterator();
diff --git a/src/java.base/share/classes/java/util/Vector.java b/src/java.base/share/classes/java/util/Vector.java
index 869ea5dd463..b49701d72d7 100644
--- a/src/java.base/share/classes/java/util/Vector.java
+++ b/src/java.base/share/classes/java/util/Vector.java
@@ -1413,7 +1413,7 @@ public synchronized void replaceAll(UnaryOperator<E> operator) {
 
     @SuppressWarnings("unchecked")
     @Override
-    public synchronized void sort(Comparator<? super E> c) {
+    public synchronized void sort(@Nullable Comparator<? super E> c) {
         final int expectedModCount = modCount;
         Arrays.sort((E[]) elementData, 0, elementCount, c);
         if (modCount != expectedModCount)
diff --git a/src/java.base/share/classes/java/util/concurrent/CopyOnWriteArrayList.java b/src/java.base/share/classes/java/util/concurrent/CopyOnWriteArrayList.java
index 59a06554032..4f9be8b86a6 100644
--- a/src/java.base/share/classes/java/util/concurrent/CopyOnWriteArrayList.java
+++ b/src/java.base/share/classes/java/util/concurrent/CopyOnWriteArrayList.java
@@ -897,7 +897,7 @@ void replaceAllRange(UnaryOperator<E> operator, int i, int end) {
         setArray(es);
     }
 
-    public void sort(Comparator<? super E> c) {
+    public void sort(@Nullable Comparator<? super E> c) {
         synchronized (lock) {
             sortRange(c, 0, getArray().length);
         }