--- a/src/java.base/share/classes/jdk/internal/org/objectweb/asm/util/CheckSignatureAdapter.java	Thu Dec 13 16:14:07 2018 +0100
+++ b/src/java.base/share/classes/jdk/internal/org/objectweb/asm/util/CheckSignatureAdapter.java	Thu Dec 13 15:31:05 2018 +0100
@@ -365,7 +365,7 @@
     }
 
     private void checkClassName(final String name, final String message) {
-        if (name == null || name.length() == 0) {
+        if (name == null || name.isEmpty()) {
             throw new IllegalArgumentException(INVALID + message + " (must not be null or empty)");
         }
         for (int i = 0; i < name.length(); ++i) {
@@ -377,7 +377,7 @@
     }
 
     private void checkIdentifier(final String name, final String message) {
-        if (name == null || name.length() == 0) {
+        if (name == null || name.isEmpty()) {
             throw new IllegalArgumentException(INVALID + message + " (must not be null or empty)");
         }
         for (int i = 0; i < name.length(); ++i) {