Class DateField


  • @Deprecated
    public class DateField
    extends Object
    Deprecated.
    If you build a new index, use DateTools or NumericField instead. This class is included for use with existing indices and will be removed in a future release (possibly Lucene 4.0).
    Provides support for converting dates to strings and vice-versa. The strings are structured so that lexicographic sorting orders by date, which makes them suitable for use as field values and search terms.

    Note that this class saves dates with millisecond granularity, which is bad for TermRangeQuery and PrefixQuery, as those queries are expanded to a BooleanQuery with a potentially large number of terms when searching. Thus you might want to use DateTools instead.

    Note: dates before 1970 cannot be used, and therefore cannot be indexed when using this class. See DateTools for an alternative without such a limitation.

    Another approach is NumericUtils, which provides a sortable binary representation (prefix encoded) of numeric values, which date/time are. For indexing a Date or Calendar, just get the unix timestamp as long using Date.getTime() or Calendar.getTimeInMillis() and index this as a numeric value with NumericField and use NumericRangeQuery to query it.

    • Method Detail

      • MIN_DATE_STRING

        public static String MIN_DATE_STRING()
        Deprecated.
      • MAX_DATE_STRING

        public static String MAX_DATE_STRING()
        Deprecated.
      • dateToString

        public static String dateToString​(Date date)
        Deprecated.
        Converts a Date to a string suitable for indexing.
        Throws:
        RuntimeException - if the date specified in the method argument is before 1970
      • timeToString

        public static String timeToString​(long time)
        Deprecated.
        Converts a millisecond time to a string suitable for indexing.
        Throws:
        RuntimeException - if the time specified in the method argument is negative, that is, before 1970
      • stringToTime

        public static long stringToTime​(String s)
        Deprecated.
        Converts a string-encoded date into a millisecond time.
      • stringToDate

        public static Date stringToDate​(String s)
        Deprecated.
        Converts a string-encoded date into a Date object.