--- a/jdk/src/share/classes/java/security/Signature.java	Mon Jun 17 16:24:48 2013 -0700
+++ b/jdk/src/share/classes/java/security/Signature.java	Mon Jun 17 17:36:20 2013 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2013, 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
@@ -248,6 +248,7 @@
         Signature sig;
         if (instance.impl instanceof Signature) {
             sig = (Signature)instance.impl;
+            sig.algorithm = algorithm;
         } else {
             SignatureSpi spi = (SignatureSpi)instance.impl;
             sig = new Delegate(spi, algorithm);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/security/Signature/SignatureGetAlgorithm.java	Mon Jun 17 17:36:20 2013 -0700
@@ -0,0 +1,112 @@
+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * Portions Copyright (c) 2013 IBM Corporation
+ */
+
+/*
+ * @test
+ * @bug 8014620
+ * @summary Signature.getAlgorithm return null in special case
+ * @run main/othervm SignatureGetAlgorithm
+ * @author youdwei
+ */
+import java.security.*;
+
+public class SignatureGetAlgorithm {
+
+    public static void main(String[] args) throws Exception {
+        Provider testProvider = new TestProvider();
+        Security.addProvider(testProvider);
+        Signature sig = Signature.getInstance("MySignatureAlg");
+        String algorithm = sig.getAlgorithm();
+        System.out.println("Algorithm Name: " + algorithm);
+        if (algorithm == null) {
+            throw new Exception("algorithm name should be 'MySignatureAlg'");
+        }
+    }
+
+    public static class TestProvider extends Provider {
+        TestProvider() {
+            super("test", 1.0, "test");
+            put("Signature.MySignatureAlg",
+                "SignatureGetAlgorithm$MySignatureAlg");
+        }
+    }
+
+    public static class MySignatureAlg extends Signature {
+
+        public MySignatureAlg() {
+            super(null);
+        }
+
+        MySignatureAlg(String s) {
+            super(s);
+        }
+
+        @Override
+        protected void engineInitVerify(PublicKey publicKey)
+                throws InvalidKeyException {
+        }
+
+        @Override
+        protected void engineInitSign(PrivateKey privateKey)
+                throws InvalidKeyException {
+        }
+
+        @Override
+        protected void engineUpdate(byte b) throws SignatureException {
+        }
+
+        @Override
+        protected void engineUpdate(byte[] b, int off, int len)
+                throws SignatureException {
+        }
+
+        @Override
+        protected byte[] engineSign()
+                throws SignatureException {
+            return new byte[0];
+        }
+
+        @Override
+        protected boolean engineVerify(byte[] sigBytes)
+                throws SignatureException {
+            return false;
+        }
+
+        @Override
+        @Deprecated
+        protected void engineSetParameter(String param, Object value)
+                throws InvalidParameterException {
+        }
+
+        @Override
+        @Deprecated
+        protected Object engineGetParameter(String param)
+                throws InvalidParameterException {
+            return null;
+        }
+    }
+}