--- a/src/java.base/share/classes/sun/util/locale/InternalLocaleBuilder.java	Thu Dec 13 16:14:07 2018 +0100
+++ b/src/java.base/share/classes/sun/util/locale/InternalLocaleBuilder.java	Thu Dec 13 15:31:05 2018 +0100
@@ -331,7 +331,7 @@
                 done.add(key);
             }
         }
-        if (privateuse != null && privateuse.length() > 0) {
+        if (privateuse != null && !privateuse.isEmpty()) {
             // privateuse string contains prefix, e.g. "x-abc-def"
             if (extensions == null) {
                 extensions = new HashMap<>(1);
@@ -406,19 +406,19 @@
         // Validate base locale fields before updating internal state.
         // LocaleExtensions always store validated/canonicalized values,
         // so no checks are necessary.
-        if (language.length() > 0 && !LanguageTag.isLanguage(language)) {
+        if (!language.isEmpty() && !LanguageTag.isLanguage(language)) {
             throw new LocaleSyntaxException("Ill-formed language: " + language);
         }
 
-        if (script.length() > 0 && !LanguageTag.isScript(script)) {
+        if (!script.isEmpty() && !LanguageTag.isScript(script)) {
             throw new LocaleSyntaxException("Ill-formed script: " + script);
         }
 
-        if (region.length() > 0 && !LanguageTag.isRegion(region)) {
+        if (!region.isEmpty() && !LanguageTag.isRegion(region)) {
             throw new LocaleSyntaxException("Ill-formed region: " + region);
         }
 
-        if (variant.length() > 0) {
+        if (!variant.isEmpty()) {
             int errIdx = checkVariants(variant, BaseLocale.SEP);
             if (errIdx != -1) {
                 throw new LocaleSyntaxException("Ill-formed variant: " + variant, errIdx);