xapian-core/matcher/valuerangepostlist.h

   1 /** @file valuerangepostlist.h
   2  * @brief Return document ids matching a range test on a specified doc value.
   3  */
   4 /* Copyright 2007,2008,2009,2011 Olly Betts
   5  * Copyright 2009 Lemur Consulting Ltd
   6  * Copyright 2010 Richard Boulton
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  21  */
  22
  23 #ifndef XAPIAN_INCLUDED_VALUERANGEPOSTLIST_H
  24 #define XAPIAN_INCLUDED_VALUERANGEPOSTLIST_H
  25
  26 #include "api/postlist.h"
  27 #include "backends/valuelist.h"
  28 #include "xapian/database.h"
  29
  30 class ValueRangePostList : public PostList {
  31   protected:
  32     const Xapian::Database::Internal *db;
  33
  34     Xapian::valueno slot;
  35
  36     const std::string begin, end;
  37
  38     Xapian::doccount db_size;
  39
  40     ValueList * valuelist;
  41
  42     /// Disallow copying.
  43     ValueRangePostList(const ValueRangePostList &);
  44
  45     /// Disallow assignment.
  46     void operator=(const ValueRangePostList &);
  47
  48   public:
  49     ValueRangePostList(const Xapian::Database::Internal *db_,
  50                        Xapian::valueno slot_,
  51                        const std::string &begin_, const std::string &end_)
  52         : db(db_), slot(slot_), begin(begin_), end(end_),
  53           db_size(db->get_doccount()), valuelist(0) { }
  54
  55     ~ValueRangePostList();
  56
  57     Xapian::doccount get_termfreq_min() const;
  58
  59     Xapian::doccount get_termfreq_est() const;
  60
  61     Xapian::doccount get_termfreq_max() const;
  62
  63     TermFreqs get_termfreq_est_using_stats(
  64         const Xapian::Weight::Internal & stats) const;
  65
  66     Xapian::docid get_docid() const;
  67
  68     double get_weight(Xapian::termcount doclen,
  69                       Xapian::termcount unique_terms) const;
  70
  71     double recalc_maxweight();
  72
  73     PositionList * read_position_list();
  74
  75     PostList * next(double w_min);
  76
  77     PostList * skip_to(Xapian::docid, double w_min);
  78
  79     PostList * check(Xapian::docid did, double w_min, bool &valid);
  80
  81     bool at_end() const;
  82
  83     Xapian::termcount count_matching_subqs() const;
  84
  85     std::string get_description() const;
  86 };
  87
  88 #endif /* XAPIAN_INCLUDED_VALUERANGEPOSTLIST_H */