--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/lib/jdk/test/lib/util/JarUtils.java	Tue May 30 21:07:14 2017 -0700
@@ -0,0 +1,148 @@
+/*
+ * Copyright (c) 2015, 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.test.lib.util;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.jar.JarOutputStream;
+import java.util.jar.Manifest;
+
+/**
+ * Common library for various test jar file utility functions.
+ */
+public final class JarUtils {
+
+    /**
+     * Create jar file with specified files. If a specified file does not exist,
+     * a new jar entry will be created with the file name itself as the content.
+     */
+    public static void createJar(String dest, String... files)
+            throws IOException {
+        try (JarOutputStream jos = new JarOutputStream(
+                new FileOutputStream(dest), new Manifest())) {
+            for (String file : files) {
+                System.out.println(String.format("Adding %s to %s",
+                        file, dest));
+
+                // add an archive entry, and write a file
+                jos.putNextEntry(new JarEntry(file));
+                try (FileInputStream fis = new FileInputStream(file)) {
+                    fis.transferTo(jos);
+                } catch (FileNotFoundException e) {
+                    jos.write(file.getBytes());
+                }
+            }
+        }
+        System.out.println();
+    }
+
+    /**
+     * Add or remove specified files to existing jar file. If a specified file
+     * to be updated or added does not exist, the jar entry will be created
+     * with the file name itself as the content.
+     *
+     * @param src the original jar file name
+     * @param dest the new jar file name
+     * @param files the files to update. The list is broken into 2 groups
+     *              by a "-" string. The files before in the 1st group will
+     *              be either updated or added. The files in the 2nd group
+     *              will be removed. If no "-" exists, all files belong to
+     *              the 1st group.
+     */
+    public static void updateJar(String src, String dest, String... files)
+            throws IOException {
+        try (JarOutputStream jos = new JarOutputStream(
+                new FileOutputStream(dest))) {
+
+            // copy each old entry into destination unless the entry name
+            // is in the updated list
+            List<String> updatedFiles = new ArrayList<>();
+            try (JarFile srcJarFile = new JarFile(src)) {
+                Enumeration<JarEntry> entries = srcJarFile.entries();
+                while (entries.hasMoreElements()) {
+                    JarEntry entry = entries.nextElement();
+                    String name = entry.getName();
+                    boolean found = false;
+                    boolean update = true;
+                    for (String file : files) {
+                        if (file.equals("-")) {
+                            update = false;
+                        } else if (name.equals(file)) {
+                            updatedFiles.add(file);
+                            found = true;
+                            break;
+                        }
+                    }
+
+                    if (found) {
+                        if (update) {
+                            System.out.println(String.format("Updating %s with %s",
+                                    dest, name));
+                            jos.putNextEntry(new JarEntry(name));
+                            try (FileInputStream fis = new FileInputStream(name)) {
+                                fis.transferTo(jos);
+                            } catch (FileNotFoundException e) {
+                                jos.write(name.getBytes());
+                            }
+                        } else {
+                            System.out.println(String.format("Removing %s from %s",
+                                    name, dest));
+                        }
+                    } else {
+                        System.out.println(String.format("Copying %s to %s",
+                                name, dest));
+                        jos.putNextEntry(entry);
+                        srcJarFile.getInputStream(entry).transferTo(jos);
+                    }
+                }
+            }
+
+            // append new files
+            for (String file : files) {
+                if (file.equals("-")) {
+                    break;
+                }
+                if (!updatedFiles.contains(file)) {
+                    System.out.println(String.format("Adding %s with %s",
+                            dest, file));
+                    jos.putNextEntry(new JarEntry(file));
+                    try (FileInputStream fis = new FileInputStream(file)) {
+                        fis.transferTo(jos);
+                    } catch (FileNotFoundException e) {
+                        jos.write(file.getBytes());
+                    }
+                }
+            }
+        }
+        System.out.println();
+    }
+
+}