--- old/src/java.base/share/classes/java/net/MulticastSocket.java	2020-01-14 19:13:43.000000000 +0000
+++ new/src/java.base/share/classes/java/net/MulticastSocket.java	2020-01-14 19:13:43.000000000 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1995, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1995, 2020, 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
@@ -29,6 +29,7 @@
 import java.util.Collections;
 import java.util.Enumeration;
 import java.util.Set;
+
 /**
  * The multicast datagram socket class is useful for sending
  * and receiving IP multicast packets. A MulticastSocket is
@@ -208,6 +209,10 @@
     public MulticastSocket(SocketAddress bindaddr) throws IOException {
         super((SocketAddress) null);
 
+        // No further initialization when this is a DatagramChannel socket adaptor
+        if (this instanceof sun.nio.ch.DatagramSocketAdaptor)
+            return;
+
         // Enable SO_REUSEADDR before binding
         setReuseAddress(true);