include/xapian/queryparser.h

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00001 
00004 /* Copyright (C) 2005,2006,2007 Olly Betts
00005  *
00006  * This program is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU General Public License as
00008  * published by the Free Software Foundation; either version 2 of the
00009  * License, or (at your option) any later version.
00010  *
00011  * This program is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014  * GNU General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU General Public License
00017  * along with this program; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
00019  * USA
00020  */
00021 
00022 #ifndef XAPIAN_INCLUDED_QUERYPARSER_H
00023 #define XAPIAN_INCLUDED_QUERYPARSER_H
00024 
00025 #include <xapian/base.h>
00026 #include <xapian/query.h>
00027 #include <xapian/stem.h>
00028 #include <xapian/termiterator.h>
00029 #include <xapian/visibility.h>
00030 
00031 #include <set>
00032 #include <string>
00033 
00034 namespace Xapian {
00035 
00037 class XAPIAN_VISIBILITY_DEFAULT Stopper {
00038   public:
00040     virtual bool operator()(const std::string & term) const = 0;
00041 
00043     virtual ~Stopper() { }
00044 
00046     virtual std::string get_description() const;
00047 };
00048 
00050 class XAPIAN_VISIBILITY_DEFAULT SimpleStopper : public Stopper {
00051   private:
00052     std::set<std::string> stop_words;
00053 
00054   public:
00056     SimpleStopper() { }
00057 
00059 #ifndef __SUNPRO_CC
00060     template <class Iterator>
00061     SimpleStopper(Iterator begin, Iterator end) : stop_words(begin, end) { }
00062 #else
00063     // Sun's C++ doesn't cope with the Iterator pointing to const char *.
00064     template <class Iterator>
00065     SimpleStopper(Iterator begin, Iterator end) {
00066         while (begin != end) stop_words.insert(*begin++);
00067     }
00068 #endif
00069 
00071     void add(const std::string & word) { stop_words.insert(word); }
00072 
00074     virtual bool operator()(const std::string & term) const {
00075         return stop_words.find(term) != stop_words.end();
00076     }
00077 
00079     virtual ~SimpleStopper() { }
00080 
00082     virtual std::string get_description() const;
00083 };
00084 
00085 struct XAPIAN_VISIBILITY_DEFAULT ValueRangeProcessor {
00086     virtual ~ValueRangeProcessor();
00087     virtual Xapian::valueno operator()(std::string &begin, std::string &end) = 0;
00088 };
00089 
00090 class XAPIAN_VISIBILITY_DEFAULT StringValueRangeProcessor : public ValueRangeProcessor {
00091     Xapian::valueno valno;
00092 
00093   public:
00094     StringValueRangeProcessor(Xapian::valueno valno_)
00095         : valno(valno_) { }
00096 
00097     Xapian::valueno operator()(std::string &, std::string &) {
00098         return valno;
00099     }
00100 };
00101 
00102 class XAPIAN_VISIBILITY_DEFAULT DateValueRangeProcessor : public ValueRangeProcessor {
00103     Xapian::valueno valno;
00104     bool prefer_mdy;
00105     int epoch_year;
00106 
00107   public:
00108     DateValueRangeProcessor(Xapian::valueno valno_, bool prefer_mdy_ = false,
00109                             int epoch_year_ = 1970)
00110         : valno(valno_), prefer_mdy(prefer_mdy_), epoch_year(epoch_year_) { }
00111 
00112     Xapian::valueno operator()(std::string &begin, std::string &end);
00113 };
00114 
00115 class XAPIAN_VISIBILITY_DEFAULT NumberValueRangeProcessor : public ValueRangeProcessor {
00116     Xapian::valueno valno;
00117     bool prefix;
00118     std::string str;
00119 
00120   public:
00121     NumberValueRangeProcessor(Xapian::valueno valno_)
00122         : valno(valno_), prefix(false) { }
00123 
00124     NumberValueRangeProcessor(Xapian::valueno valno_, const std::string &str_,
00125                               bool prefix_ = true)
00126         : valno(valno_), prefix(prefix_), str(str_) { }
00127 
00128     Xapian::valueno operator()(std::string &begin, std::string &end);
00129 };
00130 
00132 class XAPIAN_VISIBILITY_DEFAULT QueryParser {
00133   public:
00135     class Internal;
00137     Xapian::Internal::RefCntPtr<Internal> internal;
00138 
00140     typedef enum {
00142         FLAG_BOOLEAN = 1,
00144         FLAG_PHRASE = 2,
00146         FLAG_LOVEHATE = 4,
00148         FLAG_BOOLEAN_ANY_CASE = 8,
00154         FLAG_WILDCARD = 16,
00161         FLAG_PURE_NOT = 32,
00170         FLAG_PARTIAL = 64
00171     } feature_flag;
00172 
00173     typedef enum { STEM_NONE, STEM_SOME, STEM_ALL } stem_strategy;
00174 
00176     QueryParser(const QueryParser & o);
00177 
00179     QueryParser & operator=(const QueryParser & o);
00180 
00182     QueryParser();
00183 
00185     ~QueryParser();
00186 
00188     void set_stemmer(const Xapian::Stem & stemmer);
00189 
00191     void set_stemming_strategy(stem_strategy strategy);
00192 
00194     void set_stopper(const Stopper *stop = NULL);
00195 
00197     void set_default_op(Query::op default_op);
00198 
00200     Query::op get_default_op() const;
00201 
00203     void set_database(const Database &db);
00204 
00214     Query parse_query(const std::string &query_string,
00215                       unsigned flags = FLAG_PHRASE|FLAG_BOOLEAN|FLAG_LOVEHATE,
00216                       const std::string &default_prefix = "");
00217 
00230     void add_prefix(const std::string &field, const std::string &prefix);
00231 
00247     void add_boolean_prefix(const std::string & field, const std::string &prefix);
00248 
00250     TermIterator stoplist_begin() const;
00251     TermIterator stoplist_end() const {
00252         return TermIterator(NULL);
00253     }
00254 
00256     TermIterator unstem_begin(const std::string &term) const;
00257     TermIterator unstem_end(const std::string &) const {
00258         return TermIterator(NULL);
00259     }
00260 
00262     void add_valuerangeprocessor(Xapian::ValueRangeProcessor * vrproc);
00263 
00265     std::string get_description() const;
00266 };
00267 
00268 }
00269 
00270 #endif // XAPIAN_INCLUDED_QUERYPARSER_H

Documentation for Xapian (version 1.0.0).
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