src/java.base/share/classes/jdk/internal/module/Checks.java

rev 52979 : 8215281: Use String.isEmpty() when applicable in java.base
Reviewed-by: TBD

*** 61,86 ****
          }
          return name;
      }
  
      /**
-      * Returns {@code true} if the given name is a legal module name.
-      */
-     public static boolean isModuleName(String name) {
-         int next;
-         int off = 0;
-         while ((next = name.indexOf('.', off)) != -1) {
-             String id = name.substring(off, next);
-             if (!isJavaIdentifier(id))
-                 return false;
-             off = next+1;
-         }
-         String last = name.substring(off);
-         return isJavaIdentifier(last);
-     }
- 
-     /**
       * Checks a name to ensure that it's a legal package name.
       *
       * @throws IllegalArgumentException if name is null or not a legal
       *         package name
       */
--- 61,70 ----
*** 179,202 ****
          }
          return name;
      }
  
      /**
!      * Returns true if the given char sequence is a legal Java identifier,
       * otherwise false.
       */
!     private static boolean isJavaIdentifier(CharSequence cs) {
!         if (cs.length() == 0 || RESERVED.contains(cs))
              return false;
  
!         int first = Character.codePointAt(cs, 0);
          if (!Character.isJavaIdentifierStart(first))
              return false;
  
          int i = Character.charCount(first);
!         while (i < cs.length()) {
!             int cp = Character.codePointAt(cs, i);
              if (!Character.isJavaIdentifierPart(cp))
                  return false;
              i += Character.charCount(cp);
          }
  
--- 163,186 ----
          }
          return name;
      }
  
      /**
!      * Returns true if the given string is a legal Java identifier,
       * otherwise false.
       */
!     private static boolean isJavaIdentifier(String str) {
!         if (str.isEmpty() || RESERVED.contains(str))
              return false;
  
!         int first = Character.codePointAt(str, 0);
          if (!Character.isJavaIdentifierStart(first))
              return false;
  
          int i = Character.charCount(first);
!         while (i < str.length()) {
!             int cp = Character.codePointAt(str, i);
              if (!Character.isJavaIdentifierPart(cp))
                  return false;
              i += Character.charCount(cp);
          }