Fix for date-handling error affecting "Europe/Moscow" timezone with Java 1.8.0_60

h2/src/main/org/h2/util/DateTimeUtils.java

@@ -501,9 +501,12 @@ public class DateTimeUtils {
      * @return the number of milliseconds in UTC
      */
     public static long getTimeUTCWithoutDst(long millis) {
-        return millis - getCalendar().get(Calendar.ZONE_OFFSET);
+        Calendar calendar = getCalendar();
+        // clearing calendar is work-around for bug with "Europe/Moscow" timezone with Java 1.8.0_60
+        // if calendar is not cleared, then subsequent calls to this method with the same input return different values.
+        calendar.clear();
+        return millis - calendar.get(Calendar.ZONE_OFFSET);
     }
-
     /**
      * Return the day of week according to the ISO 8601 specification. Week
      * starts at Monday. See also http://en.wikipedia.org/wiki/ISO_8601

h2/src/test/org/h2/test/unit/TestDate.java

@@ -473,6 +473,12 @@ public class TestDate extends TestBase {
                 ts2.getTimestamp(), Calendar.getInstance());
         assertEquals("-999-08-07 13:14:15.16", ts1a.getString());
         assertEquals("19999-08-07 13:14:15.16", ts2a.getString());
+
+        // test for bug on Java 1.8.0_60 in "Europe/Moscow" timezone. Doesn't affect most other timezones
+        long millis = 1407437460000L;
+        long result1 = DateTimeUtils.nanosFromDate(DateTimeUtils.getTimeUTCWithoutDst(millis));
+        long result2 = DateTimeUtils.nanosFromDate(DateTimeUtils.getTimeUTCWithoutDst(millis));
+        assertEquals(result1, result2);
     }
 
 }