--- old/src/share/classes/sun/nio/ch/FileDispatcher.java	2018-02-02 03:16:59.854317380 -0500
+++ new/src/share/classes/sun/nio/ch/FileDispatcher.java	2018-02-02 03:16:59.735317386 -0500
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2018, 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
@@ -40,6 +40,8 @@
 
     abstract int truncate(FileDescriptor fd, long size) throws IOException;
 
+    abstract int allocate(FileDescriptor fd, long size) throws IOException;
+
     abstract long size(FileDescriptor fd) throws IOException;
 
     abstract int lock(FileDescriptor fd, boolean blocking, long pos, long size,