diff -r eb491334113f -r 119ac9128c1b src/java.base/share/classes/sun/nio/ch/Util.java
--- a/src/java.base/share/classes/sun/nio/ch/Util.java	Fri Oct 25 14:50:16 2019 +0100
+++ b/src/java.base/share/classes/sun/nio/ch/Util.java	Fri Oct 25 15:56:35 2019 +0100
@@ -282,7 +282,7 @@
      * returning to the cache then insert it at the start so that it is
      * likely to be returned by a subsequent call to getTemporaryDirectBuffer.
      */
-    static void offerFirstTemporaryDirectBuffer(ByteBuffer buf) {
+    public static void offerFirstTemporaryDirectBuffer(ByteBuffer buf) {
         // If the buffer is too large for the cache we don't have to
         // check the cache. We'll just free it.
         if (isBufferTooLarge(buf)) {