--- /dev/null	2020-03-03 22:06:13.039758260 +0000
+++ new/test/jaxp/javax/xml/jaxp/unittest/datatype/HashCodeTest.java	2020-08-06 05:48:20.828715157 +0000
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2020, 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 datatype;
+
+import javax.xml.datatype.DatatypeFactory;
+import javax.xml.datatype.XMLGregorianCalendar;
+import org.testng.annotations.Test;
+import org.testng.Assert;
+import org.testng.annotations.DataProvider;
+
+/*
+ * @test
+ * @bug 8246816
+ * @run testng datatype.HashCodeTest
+ * @summary Test hashCode generation.
+ */
+public class HashCodeTest {
+    /*
+       DataProvider: for testHashCode
+       Data: datetime1, datetime1, flag indicating if their hashCodes are equal
+     */
+    @DataProvider(name = "testHashCode")
+    public Object[][] getData() {
+
+        return new Object[][]{
+            // the reported case: identical hash codes before the patch
+            {"2020-04-24T12:53:00+02:00", "2020-06-04T06:58:17.727Z", false},
+            {"1002000-01-15T12:00:00-05:00", "2002000-01-15T13:00:00-04:00", false},
+            {"2000-01-15T12:00:59.99999-05:00", "2000-01-15T13:00:59-04:00", false},
+            {"2000-01-15T12:00:00-05:00", "2000-01-15T13:00:00-04:00", true},
+            {"2000-01-15T12:00:59.99999-05:00", "2000-01-15T13:00:59.99999-04:00", true},
+            {"999999999-01-15T12:00:00-05:00", "999999999-01-15T13:00:00-04:00", true},
+            {"999999999-01-15T12:00:59.99999-05:00", "999999999-01-15T13:00:59.99999-04:00", true},
+        };
+    }
+
+    @Test(dataProvider = "testHashCode")
+    public final void testHashCode(String dt1, String dt2, boolean equal) throws Exception {
+        DatatypeFactory dataTypeFactory = DatatypeFactory.newInstance();
+        XMLGregorianCalendar cal1 = dataTypeFactory.newXMLGregorianCalendar(dt1);
+        XMLGregorianCalendar cal2 = dataTypeFactory.newXMLGregorianCalendar(dt2);
+
+        // identical hash codes before the patch
+        int hashCode1 = cal1.hashCode();
+        int hashCode2 = cal2.hashCode();
+
+        if (equal) {
+            Assert.assertTrue(cal1.equals(cal2));
+            Assert.assertEquals(hashCode1, hashCode2);
+        } else {
+            Assert.assertFalse(cal1.equals(cal2));
+            Assert.assertNotEquals(hashCode1, hashCode2);
+        }
+    }
+}