--- /dev/null	2016-05-17 12:01:17.473251102 +0900
+++ new/test/java/text/Format/NumberFormat/Bug4990596.java	2016-05-26 10:32:21.642917003 +0900
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2004, 2016, 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 4990596
+ * @summary Make sure that any subclass of Number can be formatted using DecimalFormat.format().
+ */
+
+import java.text.DecimalFormat;
+
+public class Bug4990596 {
+
+    public static void main(String[] args) {
+        new DecimalFormat().format(new MutableInteger(0));
+    }
+
+    public static class MutableInteger extends Number {
+        public int value;
+
+        public MutableInteger() {
+        }
+        public MutableInteger(int value) {
+            this.value = value;
+        }
+        public double doubleValue() {
+            return this.value;
+        }
+        public float floatValue() {
+            return this.value;
+        }
+        public int intValue() {
+            return this.value;
+        }
+        public long longValue() {
+            return this.value;
+        }
+    }
+}