2 files changed, 10 insertions, 7 deletions
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeUtils.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeUtils.scala
index df480a1d65..0b643a5b84 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeUtils.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/util/DateTimeUtils.scala
@@ -852,8 +852,10 @@ object DateTimeUtils {
 
   /**
    * Lookup the offset for given millis seconds since 1970-01-01 00:00:00 in given timezone.
+   * TODO: Improve handling of normalization differences.
+   * TODO: Replace with JSR-310 or similar system - see SPARK-16788
    */
-  private def getOffsetFromLocalMillis(millisLocal: Long, tz: TimeZone): Long = {
+  private[sql] def getOffsetFromLocalMillis(millisLocal: Long, tz: TimeZone): Long = {
     var guess = tz.getRawOffset
     // the actual offset should be calculated based on milliseconds in UTC
     val offset = tz.getOffset(millisLocal - guess)
@@ -875,11 +877,11 @@ object DateTimeUtils {
         val hh = seconds / 3600
         val mm = seconds / 60 % 60
         val ss = seconds % 60
-        val nano = millisOfDay % 1000 * 1000000
-
-        // create a Timestamp to get the unix timestamp (in UTC)
-        val timestamp = new Timestamp(year - 1900, month - 1, day, hh, mm, ss, nano)
-        guess = (millisLocal - timestamp.getTime).toInt
+        val ms = millisOfDay % 1000
+        val calendar = Calendar.getInstance(tz)
+        calendar.set(year, month - 1, day, hh, mm, ss)
+        calendar.set(Calendar.MILLISECOND, ms)
+        guess = (millisLocal - calendar.getTimeInMillis()).toInt
       }
     }
     guess
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeUtilsSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeUtilsSuite.scala
index 059a5b7d07..4f516d0064 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeUtilsSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/util/DateTimeUtilsSuite.scala
@@ -551,7 +551,8 @@ class DateTimeUtilsSuite extends SparkFunSuite {
         val skipped = skipped_days.getOrElse(tz.getID, Int.MinValue)
         (-20000 to 20000).foreach { d =>
           if (d != skipped) {
-            assert(millisToDays(daysToMillis(d)) === d)
+            assert(millisToDays(daysToMillis(d)) === d,
+              s"Round trip of ${d} did not work in tz ${tz}")
           }
         }
       }