--- old/src/java.base/share/classes/java/nio/file/Files.java	2017-12-22 15:05:50.000000000 -0800
+++ new/src/java.base/share/classes/java/nio/file/Files.java	2017-12-22 15:05:49.000000000 -0800
@@ -77,6 +77,8 @@
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
+import jdk.internal.io.IOSupport;
+
 import sun.nio.fs.AbstractFileSystemProvider;
 
 /**
@@ -3066,7 +3068,7 @@
 
         // do the copy
         try (OutputStream out = ostream) {
-            return in.transferTo(out);
+            return IOSupport.copy(in, out);
         }
     }
 
@@ -3108,7 +3110,7 @@
         Objects.requireNonNull(out);
 
         try (InputStream in = newInputStream(source)) {
-            return in.transferTo(out);
+            return IOSupport.copy(in, out);
         }
     }