--- /dev/null	2009-01-20 02:47:15.000000000 -0800
+++ new/src/share/projects/meth/src/impl/java/dyn/Access.java	2009-01-20 02:47:14.000000000 -0800
@@ -0,0 +1,93 @@
+/*
+ * Copyright 2008-2009 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package impl.java.dyn;
+
+import java.dyn.MethodHandles;
+import sun.reflect.Reflection;
+
+/**
+ * Access control to this package.
+ * Classes in other packages can attempt to acquire the access token,
+ * but will fail if they are not recognized as friends.
+ * Certain methods in this package, although public, require a non-null
+ * access token in order to proceed; they act like package-private methods.
+ * @author jrose
+ */
+
+public class Access {
+    private Access() { }
+
+    /**
+     * The heart of this pattern:  The list of classes which are
+     * permitted to acquire the access token, and become honorary
+     * members of this package.
+     */
+    static private final String[] FRIENDS = {
+        "java.dyn.", "impl.java.dyn."
+    };
+
+    /**
+     * The following object is NOT public.  That's the point of the pattern.
+     * It is package-private, so that any member of this package
+     * can acquire the access token, and give it away to trusted friends.
+     */
+    static final Access TOKEN = new Access();
+
+    /**
+     * @return Access.TOKEN, if the caller is a friend of this package
+     */
+    public static Access getToken() {
+        Class<?> callc = Reflection.getCallerClass(2);
+        if (callc.getClassLoader() == Access.class.getClassLoader()) {
+            String callcName = callc.getName();
+            for (String friend : FRIENDS) {
+                if (callcName.startsWith(friend))
+                    return TOKEN;
+            }
+        }
+        throw new IllegalAccessError("bad caller: " + callc);
+    }
+
+    /**
+     * Throw an IllegalAccessError if the caller does not possess
+     * the Access.TOKEN.
+     * @param must be Access.TOKEN
+     */
+    public static void check(Access token) {
+        if (token == null)
+            fail();
+        // else it must be the unique Access.TOKEN
+        assert(token == Access.TOKEN);
+    }
+    private static void fail() {
+        Class<?> callc = Reflection.getCallerClass(3);
+        throw new IllegalAccessError("bad caller: " + callc);
+    }
+
+    static {
+        //sun.reflect.Reflection.registerMethodsToFilter(MH.class, "getToken");
+    }
+}