Added Java 6 compatibility.
package net.finmath.time;
+import org.threeten.bp.DayOfWeek;
import org.threeten.bp.Instant;
import org.threeten.bp.LocalDate;
import org.threeten.bp.ZoneId;
-import java.time.format.DateTimeFormatter;
-import java.time.format.DateTimeFormatterBuilder;
-import java.time.format.DateTimeParseException;
+import org.threeten.bp.format.DateTimeFormatter;
+import org.threeten.bp.format.DateTimeFormatterBuilder;
+import org.threeten.bp.format.DateTimeParseException;
import java.util.ArrayList;
import java.util.Date;
import java.util.Locale;
