8345668: ZoneOffset.ofTotalSeconds performance regression

src/java.base/share/classes/java/time/ZoneOffset.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -424,11 +424,17 @@ public static ZoneOffset ofTotalSeconds(int totalSeconds) {
             throw new DateTimeException("Zone offset not in valid range: -18:00 to +18:00");
         }
         if (totalSeconds % (15 * SECONDS_PER_MINUTE) == 0) {
-            return SECONDS_CACHE.computeIfAbsent(totalSeconds, totalSecs -> {
-                ZoneOffset result = new ZoneOffset(totalSecs);
+            Integer totalSecs = totalSeconds;
+            ZoneOffset result = SECONDS_CACHE.get(totalSecs);
+            if (result == null) {
+                result = new ZoneOffset(totalSeconds);
+                var existing = SECONDS_CACHE.putIfAbsent(totalSecs, result);
+                if (existing != null) {
+                    result = existing;
+                }
                 ID_CACHE.putIfAbsent(result.getId(), result);
-                return result;
-            });
+            }
+            return result;
         } else {
             return new ZoneOffset(totalSeconds);
         }

src/java.base/share/classes/java/time/format/DateTimeTextProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -309,7 +309,15 @@ public Iterator<Entry<String, Long>> getTextIterator(Chronology chrono, Temporal
 
     private Object findStore(TemporalField field, Locale locale) {
         Entry<TemporalField, Locale> key = createEntry(field, locale);
-        return CACHE.computeIfAbsent(key, e -> createStore(e.getKey(), e.getValue()));
+        Object store = CACHE.get(key);
+        if (store == null) {
+            store = createStore(field, locale);
+            var existing = CACHE.putIfAbsent(key, store);
+            if (existing != null) {
+                store = existing;
+            }
+        }
+        return store;
     }
 
     private static int toWeekDay(int calWeekDay) {

src/java.base/share/classes/java/time/format/DecimalStyle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -160,7 +160,15 @@ public static DecimalStyle ofDefaultLocale() {
      */
     public static DecimalStyle of(Locale locale) {
         Objects.requireNonNull(locale, "locale");
-        return CACHE.computeIfAbsent(locale, DecimalStyle::create);
+        DecimalStyle info = CACHE.get(locale);
+        if (info == null) {
+            info = create(locale);
+            var existing = CACHE.putIfAbsent(locale, info);
+            if (existing != null) {
+                info = existing;
+            }
+        }
+        return info;
     }
 
     private static DecimalStyle create(Locale locale) {