Replace getTimeZoneName() with getTimeZone()

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

@@ -331,7 +331,7 @@ public class DateTimeUtils {
             cal.setTime(value.getTime());
         } else if (value instanceof ValueTimestampTimeZone) {
             ValueTimestampTimeZone v = (ValueTimestampTimeZone) value;
-            cal = createGregorianCalendar(TimeZone.getTimeZone(v.getTimeZoneName()));
+            cal = createGregorianCalendar(v.getTimeZone());
             cal.setTimeInMillis(DateTimeUtils.convertDateValueToMillis(DateTimeUtils.UTC, v.getDateValue())
                     + v.getTimeNanos() / 1000000L
                     - v.getTimeZoneOffsetMins() * 60000);

h2/src/main/org/h2/value/ValueTimestampTimeZone.java

@@ -9,6 +9,7 @@ import java.math.BigDecimal;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 import java.sql.Timestamp;
+import java.util.SimpleTimeZone;
 import java.util.TimeZone;
 import org.h2.api.ErrorCode;
 import org.h2.api.TimestampWithTimeZone;
@@ -202,27 +203,16 @@ public class ValueTimestampTimeZone extends Value {
     }
 
     /**
-     * Returns name of the timezone such as UTC or GMT+1:00.
+     * Returns compatible offset-based time zone with no DST schedule.
      *
-     * @return name of the timezone
+     * @return compatible offset-based time zone
      */
-    public String getTimeZoneName() {
+    public TimeZone getTimeZone() {
         int offset = timeZoneOffsetMins;
-        if (offset == 0)
-            return "UTC";
-        StringBuilder builder = new StringBuilder("GMT");
-        if (offset > 0) {
-            builder.append('+');
-        } else {
-            builder.append('-');
-            offset = -offset;
-        }
-        builder.append(offset / 60).append(':');
-        offset %= 60;
-        if (offset < 10)
-            builder.append('0');
-        builder.append(offset);
-        return builder.toString();
+        if (offset == 0) {
+            return DateTimeUtils.UTC;
+        }
+        return new SimpleTimeZone(offset * 60000, Integer.toString(offset));
     }
 
     @Override