--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/GenerateJLIClassesHelper.java	Wed Aug 10 22:49:05 2016 +0200
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2016, 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 java.lang.invoke;
+
+import java.util.Map;
+import jdk.internal.org.objectweb.asm.ClassWriter;
+import jdk.internal.org.objectweb.asm.Opcodes;
+
+/**
+ * Helper class to assist the GenerateJLIClassesPlugin to get access to
+ * generate classes ahead of time.
+ */
+class GenerateJLIClassesHelper {
+
+    static byte[] generateDMHClassBytes(String className,
+            MethodType[] methodTypes, int[] types) {
+        LambdaForm[] forms = new LambdaForm[methodTypes.length];
+        for (int i = 0; i < forms.length; i++) {
+            forms[i] = DirectMethodHandle.makePreparedLambdaForm(methodTypes[i],
+                                                                 types[i]);
+            methodTypes[i] = forms[i].methodType();
+        }
+        return generateCodeBytesForLFs(className, forms, methodTypes);
+    }
+
+    /*
+     * Generate customized code for a set of LambdaForms of specified types into
+     * a class with a specified name.
+     */
+    private static byte[] generateCodeBytesForLFs(String className,
+            LambdaForm[] forms, MethodType[] types) {
+        assert(forms.length == types.length);
+
+        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
+        cw.visit(Opcodes.V1_8, Opcodes.ACC_PRIVATE + Opcodes.ACC_FINAL + Opcodes.ACC_SUPER,
+                className, null, InvokerBytecodeGenerator.INVOKER_SUPER_NAME, null);
+        cw.visitSource(className.substring(className.lastIndexOf('/') + 1), null);
+        for (int i = 0; i < forms.length; i++) {
+            InvokerBytecodeGenerator g
+                    = new InvokerBytecodeGenerator(className, forms[i], types[i]);
+            g.setClassWriter(cw);
+            g.addMethod();
+        }
+        return cw.toByteArray();
+    }
+
+    static Map.Entry<String, byte[]> generateConcreteBMHClassBytes(
+            final String types) {
+        for (char c : types.toCharArray()) {
+            if ("LIJFD".indexOf(c) < 0) {
+                throw new IllegalArgumentException("All characters must "
+                        + "correspond to a basic field type: LIJFD");
+            }
+        }
+        String shortTypes = LambdaForm.shortenSignature(types);
+        final String className =
+                BoundMethodHandle.Factory.speciesInternalClassName(shortTypes);
+        return Map.entry(className,
+                         BoundMethodHandle.Factory.generateConcreteBMHClassBytes(
+                                 shortTypes, types, className));
+    }
+}