src/java.base/windows/classes/java/io/WinNTFileSystem.java

*** 1,7 ****
  /*
!  * Copyright (c) 2001, 2012, 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
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2001, 2016, 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
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 23,32 ****
--- 23,34 ----
   * questions.
   */
  
  package java.io;
  
+ import java.io.File;
+ import java.nio.file.Path;
  import java.util.Locale;
  import java.util.Properties;
  import sun.security.action.GetPropertyAction;
  
  /**
*** 625,634 ****
--- 627,657 ----
  
      private native long getSpace0(File f, int t);
  
      /* -- Basic infrastructure -- */
  
+     // Obtain maximum file component length from GetVolumeInformation which
+     // expects the path to be null or a root component ending in a backslash
+     private native long getNameMax0(String path);
+ 
+     public long getNameMax(String path) {
+         String s = null;
+         if (path != null) {
+             File f = new File(path);
+             if (f.isAbsolute()) {
+                 Path root = f.toPath().getRoot();
+                 if (root != null) {
+                     s = root.toString();
+                     if (!s.endsWith("\\")) {
+                         s = s + "\\";
+                     }
+                 }
+             }
+         }
+         return getNameMax0(s);
+     }
+ 
      @Override
      public int compare(File f1, File f2) {
          return f1.getPath().compareToIgnoreCase(f2.getPath());
      }