--- old/src/java.base/share/classes/jdk/internal/module/Checks.java	2017-02-07 13:13:42.916895990 +0000
+++ new/src/java.base/share/classes/jdk/internal/module/Checks.java	2017-02-07 13:13:42.748884453 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2009, 2017, 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
@@ -26,7 +26,7 @@
 package jdk.internal.module;
 
 /**
- * Utility class for checking module name and binary names.
+ * Utility class for checking module, package, and class names.
  */
 
 public final class Checks {
@@ -58,8 +58,6 @@
             throw new IllegalArgumentException(name + ": Invalid module name"
                     + ": '" + id + "' is not a Java identifier");
         }
-        //if (!Character.isJavaIdentifierStart(last))
-        //    throw new IllegalArgumentException(name + ": Module name ends in digit");
         return name;
     }
 
@@ -77,8 +75,6 @@
         int last = isJavaIdentifier(name, off, name.length() - off);
         if (last == -1)
             return false;
-        //if (!Character.isJavaIdentifierStart(last))
-        //    return false;
         return true;
     }
 
@@ -89,40 +85,62 @@
      *         package name
      */
     public static String requirePackageName(String name) {
-        return requireBinaryName("package name", name);
+        return requireTypeName("package name", name);
     }
 
     /**
-     * Checks a name to ensure that it's a legal type name.
+     * Returns {@code true} if the given name is a legal package name.
+     */
+    public static boolean isPackageName(String name) {
+        return isTypeName(name);
+    }
+
+    /**
+     * Checks a name to ensure that it's a legal qualified class name
      *
      * @throws IllegalArgumentException if name is null or not a legal
-     *         type name
+     *         qualified class name
      */
     public static String requireServiceTypeName(String name) {
-        return requireBinaryName("service type name", name);
+        return requireQualifiedClassName("service type name", name);
     }
 
     /**
-     * Checks a name to ensure that it's a legal type name.
+     * Checks a name to ensure that it's a legal qualified class name.
      *
      * @throws IllegalArgumentException if name is null or not a legal
-     *         type name
+     *         qualified class name
      */
     public static String requireServiceProviderName(String name) {
-        return requireBinaryName("service provider name", name);
+        return requireQualifiedClassName("service provider name", name);
+    }
+
+    /**
+     * Checks a name to ensure that it's a legal qualified class name in
+     * a named package.
+     *
+     * @throws IllegalArgumentException if name is null or not a legal
+     *         qualified class name in a named package
+     */
+    public static String requireQualifiedClassName(String what, String name) {
+        requireTypeName(what, name);
+        if (name.indexOf('.') == -1)
+            throw new IllegalArgumentException(name + ": is not a qualified name of"
+                                               + " a Java class in a named package");
+        return name;
     }
 
     /**
-     * Returns {@code true} if the given name is a legal binary name.
+     * Returns {@code true} if the given name is a legal class name.
      */
-    public static boolean isJavaIdentifier(String name) {
-        return isBinaryName(name);
+    public static boolean isClassName(String name) {
+        return isTypeName(name);
     }
 
     /**
-     * Returns {@code true} if the given name is a legal binary name.
+     * Returns {@code true} if the given name is a legal type name.
      */
-    public static boolean isBinaryName(String name) {
+    private static boolean isTypeName(String name) {
         int next;
         int off = 0;
         while ((next = name.indexOf('.', off)) != -1) {
@@ -135,12 +153,12 @@
     }
 
     /**
-     * Checks if the given name is a legal binary name.
+     * Checks if the given name is a legal type name.
      *
      * @throws IllegalArgumentException if name is null or not a legal
-     *         binary name
+     *         type name
      */
-    public static String requireBinaryName(String what, String name) {
+    private static String requireTypeName(String what, String name) {
         if (name == null)
             throw new IllegalArgumentException("Null " + what);
         int next;