--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/sun/security/tools/jarsigner/SignedAgain.java	Tue Jan 15 11:21:00 2019 +0800
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2019, 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.
+ */
+
+/*
+ * @test
+ * @bug 8215922
+ * @summary jar spec is not precise when describing jar file re-signing
+ * @library /test/lib
+ */
+
+import jdk.test.lib.Asserts;
+import jdk.test.lib.util.JarUtils;
+
+import java.io.InputStream;
+import java.security.MessageDigest;
+import java.util.Base64;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+import java.util.jar.Manifest;
+
+import static jdk.test.lib.SecurityTools.*;
+
+public class SignedAgain {
+    public static void main(String[] args) throws Exception {
+
+        String opt = "-storepass changeit -keystore ks";
+
+        keytool(opt + " -genkeypair -alias a -dname CN=A -keyalg RSA");
+        keytool(opt + " -genkeypair -alias b -dname CN=B -keyalg RSA");
+
+        JarUtils.createJar("a.jar", "f1");
+
+        // as.jar: signed by a
+        jarsigner(opt + " -signedjar as.jar a.jar a");
+
+        JarUtils.updateJar("as.jar", "b.jar", "f2");
+
+        // bs.jar: signed again by b
+        jarsigner(opt + " -signedjar bs.jar b.jar b");
+
+        // verified
+        jarsigner(opt + " -verify -strict -verbose -certs bs.jar")
+                .shouldHaveExitValue(0);
+
+        try (JarFile ja = new JarFile("as.jar");
+             JarFile jb = new JarFile("bs.jar");
+             InputStream ma = ja.getInputStream(
+                     new JarEntry("META-INF/MANIFEST.MF"));
+             InputStream sa = jb.getInputStream(new JarEntry("META-INF/A.SF"));
+             InputStream mb = jb.getInputStream(
+                     new JarEntry("META-INF/MANIFEST.MF"));
+             InputStream sb = jb.getInputStream(new JarEntry("META-INF/B.SF"))) {
+
+            // Hash of manifest for 2 signed JAR files
+            String da = Base64.getEncoder().encodeToString(MessageDigest
+                    .getInstance("SHA-256").digest(ma.readAllBytes()));
+            String db = Base64.getEncoder().encodeToString(MessageDigest
+                    .getInstance("SHA-256").digest(mb.readAllBytes()));
+
+            // They are not the same
+            Asserts.assertNotEquals(da, db);
+
+            // Digest-Manifest in A.SF matches da
+            Asserts.assertEQ(new Manifest(sa).getMainAttributes()
+                    .getValue("SHA-256-Digest-Manifest"), da);
+
+            // Digest-Manifest in B.SF matches db
+            Asserts.assertEQ(new Manifest(sb).getMainAttributes()
+                    .getValue("SHA-256-Digest-Manifest"), db);
+        }
+    }
+}