00001 00004 /* ----START-LICENCE---- 00005 * Copyright 1999,2000,2001 BrightStation PLC 00006 * Copyright 2002 Ananova Ltd 00007 * Copyright 2003,2004,2005 Olly Betts 00008 * 00009 * This program is free software; you can redistribute it and/or 00010 * modify it under the terms of the GNU General Public License as 00011 * published by the Free Software Foundation; either version 2 of the 00012 * License, or (at your option) any later version. 00013 * 00014 * This program is distributed in the hope that it will be useful, 00015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00017 * GNU General Public License for more details. 00018 * 00019 * You should have received a copy of the GNU General Public License 00020 * along with this program; if not, write to the Free Software 00021 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 00022 * USA 00023 * -----END-LICENCE----- 00024 */ 00025 00026 #ifndef XAPIAN_INCLUDED_POSTINGITERATOR_H 00027 #define XAPIAN_INCLUDED_POSTINGITERATOR_H 00028 00029 #include <iterator> 00030 #include <string> 00031 00032 #include <xapian/base.h> 00033 #include <xapian/types.h> 00034 #include <xapian/positioniterator.h> 00035 00036 namespace Xapian { 00037 00038 class Database; 00039 00043 class DocIDWrapper { 00044 private: 00045 docid did; 00046 public: 00047 DocIDWrapper(docid did_) : did(did_) { } 00048 docid operator*() const { return did; } 00049 }; 00050 00053 class PostingIterator { 00054 public: 00055 class Internal; 00057 Xapian::Internal::RefCntPtr<Internal> internal; 00058 00059 private: 00060 friend class Database; // So Database can construct us 00061 00062 explicit PostingIterator(Internal *internal_); 00063 00064 public: 00065 friend bool operator==(const PostingIterator &a, 00066 const PostingIterator &b); 00067 00069 PostingIterator(); 00070 00072 ~PostingIterator(); 00073 00077 PostingIterator(const PostingIterator &other); 00078 00082 void operator=(const PostingIterator &other); 00083 00084 PostingIterator & operator++(); 00085 00086 DocIDWrapper operator++(int) { 00087 Xapian::docid tmp = **this; 00088 operator++(); 00089 return DocIDWrapper(tmp); 00090 } 00091 00095 void skip_to(Xapian::docid did); 00096 00097 // Get the weight of the posting at the current position: will 00098 // need to set a weight object for this to work. 00099 // Xapian::weight get_weight() const; 00100 00102 Xapian::docid operator *() const; 00103 00113 Xapian::doclength get_doclength() const; 00114 00118 Xapian::termcount get_wdf() const; 00119 00123 PositionIterator positionlist_begin() const; 00124 00128 PositionIterator positionlist_end() const { 00129 return PositionIterator(NULL); 00130 } 00131 00132 // Don't expose these methods here. A container iterator doesn't 00133 // provide a method to find the size of the container... 00134 // Xapian::doccount get_termfreq() const; 00135 // Xapian::termcount get_collection_freq() const; 00136 00140 std::string get_description() const; 00141 00143 00144 typedef std::input_iterator_tag iterator_category; 00145 typedef Xapian::docid value_type; 00146 typedef Xapian::doccount_diff difference_type; 00147 typedef Xapian::docid * pointer; 00148 typedef Xapian::docid & reference; 00150 }; 00151 00153 inline bool operator==(const PostingIterator &a, const PostingIterator &b) 00154 { 00155 return (a.internal.get() == b.internal.get()); 00156 } 00157 00159 inline bool operator!=(const PostingIterator &a, const PostingIterator &b) 00160 { 00161 return !(a == b); 00162 } 00163 00164 } 00165 00166 #endif /* XAPIAN_INCLUDED_POSTINGITERATOR_H */