8276234: Trivially clean up locale-related code

Reviewed-by: redestad, naoto, iris

src/java.base/share/classes/java/time/chrono/JapaneseChronology.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2021, 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
@@ -124,7 +124,7 @@ public final class JapaneseChronology extends AbstractChronology implements Seri
     static final LocalGregorianCalendar JCAL =
         (LocalGregorianCalendar) CalendarSystem.forName("japanese");
 
-    // Locale for creating a JapaneseImpericalCalendar.
+    // Locale for creating a JapaneseImperialCalendar.
     static final Locale LOCALE = Locale.forLanguageTag("ja-JP-u-ca-japanese");
 
     /**

src/java.base/share/classes/sun/util/locale/BaseLocale.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2010, 2021, 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
@@ -139,7 +139,7 @@ public static BaseLocale getInstance(String language, String script,
             region = "";
         }
         if (language == null) {
-            language = null;
+            language = "";
         }
         if (variant == null) {
             variant = "";

src/java.base/share/classes/sun/util/resources/LocaleData.java

@@ -42,7 +42,6 @@
 
 import java.security.AccessController;
 import java.security.PrivilegedAction;
-import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
@@ -205,7 +204,7 @@ public OpenListResourceBundle run() {
         });
     }
 
-    private static abstract class LocaleDataResourceBundleProvider
+    private abstract static class LocaleDataResourceBundleProvider
                                             implements ResourceBundleProvider {
         /**
          * Changes baseName to its module dependent package name and
@@ -231,30 +230,30 @@ protected String toOtherBundleName(String baseName, String bundleName, Locale lo
      * A ResourceBundleProvider implementation for loading locale data
      * resource bundles except for the java.time supplementary data.
      */
-    public static abstract class CommonResourceBundleProvider extends LocaleDataResourceBundleProvider {
+    public abstract static class CommonResourceBundleProvider extends LocaleDataResourceBundleProvider {
     }
 
     /**
      * A ResourceBundleProvider implementation for loading supplementary
      * resource bundles for java.time.
      */
-    public static abstract class SupplementaryResourceBundleProvider extends LocaleDataResourceBundleProvider {
+    public abstract static class SupplementaryResourceBundleProvider extends LocaleDataResourceBundleProvider {
     }
 
     // Bundles.Strategy implementations
 
     private static class LocaleDataStrategy implements Bundles.Strategy {
         private static final LocaleDataStrategy INSTANCE = new LocaleDataStrategy();
         // TODO: avoid hard-coded Locales
-        private static Set<Locale> JAVA_BASE_LOCALES
+        private static final Set<Locale> JAVA_BASE_LOCALES
             = Set.of(Locale.ROOT, Locale.ENGLISH, Locale.US, new Locale("en", "US", "POSIX"));
 
         private LocaleDataStrategy() {
         }
 
         /*
          * This method overrides the default implementation to search
-         * from a prebaked locale string list to determin the candidate
+         * from a prebaked locale string list to determine the candidate
          * locale list.
          *
          * @param baseName the resource bundle base name.
@@ -325,16 +324,16 @@ private static class SupplementaryStrategy extends LocaleDataStrategy {
         private static final SupplementaryStrategy INSTANCE
                 = new SupplementaryStrategy();
         // TODO: avoid hard-coded Locales
-        private static Set<Locale> JAVA_BASE_LOCALES
+        private static final Set<Locale> JAVA_BASE_LOCALES
             = Set.of(Locale.ROOT, Locale.ENGLISH, Locale.US);
 
         private SupplementaryStrategy() {
         }
 
         @Override
         public List<Locale> getCandidateLocales(String baseName, Locale locale) {
-            // Specifiy only the given locale
-            return Arrays.asList(locale);
+            // Specify only the given locale
+            return List.of(locale);
         }
 
         @Override