test/java/util/Locale/LocaleProviders.java

@@ -25,10 +25,15 @@
 import sun.util.locale.provider.LocaleProviderAdapter;
 
 public class LocaleProviders {
 
     public static void main(String[] args) {
+        if (args.length == 0) {
+            // no args indicates that the caller is asking the platform default locale.
+            Locale defloc = Locale.getDefault();
+            System.out.printf("%s,%s\n", defloc.getLanguage(), defloc.getCountry());
+        } else {
         String expected = args[0];
         Locale testLocale = new Locale(args[1], args[2]);
         String preference = System.getProperty("java.locale.providers", "");
         LocaleProviderAdapter lda = LocaleProviderAdapter.getAdapter(DateFormatProvider.class, testLocale);
         LocaleProviderAdapter.Type type = lda.getAdapterType();

@@ -35,6 +40,7 @@
         System.out.printf("testLocale: %s, got: %s, expected: %s\n", testLocale, type, expected);
         if (!type.toString().equals(expected)) {
             throw new RuntimeException("Returned locale data adapter is not correct.");
         }
     }
+    }
 }