--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.dynalink/share/classes/jdk/dynalink/linker/GuardingDynamicLinkerExporter.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2015, 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 jdk.dynalink.linker;
+
+import java.security.Permission;
+import java.util.List;
+import java.util.ServiceLoader;
+import java.util.function.Supplier;
+import jdk.dynalink.DynamicLinkerFactory;
+
+/**
+ * A class acting as a supplier of guarding dynamic linkers that can be
+ * automatically loaded by other language runtimes. Language runtimes wishing
+ * to export their own linkers should subclass this class and implement the
+ * {@link #get()} method to return a list of exported linkers and declare the
+ * subclass in
+ * {@code /META-INF/services/jdk.dynalink.linker.GuardingDynamicLinkerExporter}
+ * resource of their distribution (typically, JAR file) so that dynamic linker
+ * factories can discover them using the {@link ServiceLoader} mechanism. Note
+ * that instantiating this class is tied to a security check for the
+ * {@code RuntimePermission("dynalink.exportLinkersAutomatically")} when a
+ * security manager is present, to ensure that only trusted runtimes can
+ * automatically export their linkers into other runtimes.
+ * @see DynamicLinkerFactory#setClassLoader(ClassLoader)
+ */
+public abstract class GuardingDynamicLinkerExporter implements Supplier<List<GuardingDynamicLinker>> {
+    /**
+     * The name of the runtime permission for creating instances of this class.
+     * Granting this permission to a language runtime allows it to export its
+     * linkers for automatic loading into other language runtimes.
+     */
+    public static final String AUTOLOAD_PERMISSION_NAME = "dynalink.exportLinkersAutomatically";
+
+    private static final Permission AUTOLOAD_PERMISSION = new RuntimePermission(AUTOLOAD_PERMISSION_NAME);
+
+    /**
+     * Creates a new linker exporter. If there is a security manager installed
+     * checks for the
+     * {@code RuntimePermission("dynalink.exportLinkersAutomatically")} runtime
+     * permission. This ensures only language runtimes granted this permission
+     * will be allowed to export their linkers for automatic loading.
+     * @throws SecurityException if the necessary runtime permission is not
+     * granted.
+     */
+    protected GuardingDynamicLinkerExporter() {
+        final SecurityManager sm = System.getSecurityManager();
+        if (sm != null) {
+            sm.checkPermission(AUTOLOAD_PERMISSION);
+        }
+    }
+}