--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/lib/testlibrary/bytecode/jdk/experimental/bytecode/AbstractBuilder.java	Fri Sep 08 10:46:46 2017 -0700
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ * 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.experimental.bytecode;
+
+/**
+ * Base builder.
+ *
+ * @param <S> the type of the symbol representation
+ * @param <T> the type of type descriptors representation
+ * @param <E> the type of pool entries
+ * @param <D> the type of this builder
+ */
+public class AbstractBuilder<S, T, E, D extends AbstractBuilder<S, T, E, D>> {
+    /**
+     * The helper to build the constant pool.
+     */
+    protected final PoolHelper<S, T, E> poolHelper;
+
+    /**
+     * The helper to use to manipulate type descriptors.
+     */
+    protected final TypeHelper<S, T> typeHelper;
+
+    /**
+     * Create a builder.
+     *
+     * @param poolHelper the helper to build the constant pool
+     * @param typeHelper the helper to use to manipulate type descriptors
+     */
+    AbstractBuilder(PoolHelper<S, T, E> poolHelper, TypeHelper<S, T> typeHelper) {
+        this.poolHelper = poolHelper;
+        this.typeHelper = typeHelper;
+    }
+
+    @SuppressWarnings("unchecked")
+    D thisBuilder() {
+        return (D) this;
+    }
+}