--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/sun/invoke/WrapperInstance.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2011, 2013, 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
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package sun.invoke;
+
+import java.lang.invoke.MethodHandle;
+
+/**
+ * Private API used inside of java.lang.invoke.MethodHandles.
+ * Interface implemented by every object which is produced by
+ * {@link java.lang.invoke.MethodHandleProxies#asInterfaceInstance MethodHandleProxies.asInterfaceInstance}.
+ * The methods of this interface allow a caller to recover the parameters
+ * to {@code asInstance}.
+ * This allows applications to repeatedly convert between method handles
+ * and SAM objects, without the risk of creating unbounded delegation chains.
+ */
+public interface WrapperInstance {
+    /** Produce or recover a target method handle which is behaviorally
+     *  equivalent to the SAM method of this object.
+     */
+    public MethodHandle getWrapperInstanceTarget();
+    /** Recover the SAM type for which this object was created.
+     */
+    public Class<?> getWrapperInstanceType();
+}
+