--- /dev/null	2018-05-14 10:15:02.574213890 -0700
+++ new/test/hotspot/jtreg/vmTestbase/vm/runtime/defmeth/shared/BuildJar.java	2018-05-21 10:53:06.477502341 -0700
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2017, 2018, 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 vm.runtime.defmeth.shared;
+
+import jdk.test.lib.JDKToolLauncher;
+import jdk.test.lib.Utils;
+import jdk.test.lib.process.ProcessTools;
+import jdk.test.lib.util.JarUtils;
+
+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Arrays;
+
+/**
+ * Build {@code retransform.jar} in current directory using
+ * {@code vm/runtime/defmeth/shared/retransform.mf} and classes from
+ * {@code vm.runtime.defmeth.shared} package.
+ */
+public class BuildJar {
+    public static void main(String[] args) {
+        Path manifest = testRoot().resolve("vmTestbase")
+                                  .resolve("vm")
+                                  .resolve("runtime")
+                                  .resolve("defmeth")
+                                  .resolve("shared")
+                                  .resolve("retransform.mf")
+                                  .toAbsolutePath();
+        if (Files.notExists(manifest)) {
+            throw new Error("can't find manifest file: " + manifest);
+        }
+
+        Path file = foundInClassPath(Util.Transformer.class).toAbsolutePath();
+        // Util$Transformer.class is in vm/runtime/defmeth/shared
+        Path dir = file.getParent()
+                       .getParent()
+                       .getParent()
+                       .getParent()
+                       .getParent()
+                       .toAbsolutePath();
+
+        JDKToolLauncher jar = JDKToolLauncher.create("jar")
+                                             .addToolArg("cmf")
+                                             .addToolArg(manifest.toString())
+                                             .addToolArg("retransform.jar")
+                                             .addToolArg("-C")
+                                             .addToolArg(dir.toString())
+                                             .addToolArg(dir.relativize(file).toString());
+        String[] command = jar.getCommand();
+        try {
+            ProcessTools.executeCommand(command)
+                        .shouldHaveExitValue(0);
+        } catch (Error | RuntimeException e) {
+            throw e;
+        } catch (Throwable e) {
+            throw new Error("execution of jar [" + Arrays.toString(command) + "] failed", e);
+        }
+    }
+
+    private static Path foundInClassPath(Class<?> aClass) {
+        Path file = Paths.get(aClass.getName()
+                                    .replace(".", File.separator) + ".class");
+        for (String dir : Utils.TEST_CLASS_PATH.split(File.pathSeparator)) {
+            Path result = Paths.get(dir).resolve(file);
+            if (Files.exists(result)) {
+                return result;
+            }
+        }
+        throw new Error("can't find " + file + " in " + Utils.TEST_CLASS_PATH);
+    }
+
+    private static Path testRoot() {
+        Path p = Paths.get(Utils.TEST_SRC);
+        while (!Files.exists(p.resolve("TEST.ROOT"))) {
+            p = p.getParent();
+        }
+        return p;
+    }
+}
+