XSBQuery.h Source File

00001 // See the file LICENSE in the some directory as this file for legal
00002 // notices about this software.
00003 #ifndef DEV_W3_ORG__2001_BLINDFOLD_SRC_XSBMATCH_H
00004 #define DEV_W3_ORG__2001_BLINDFOLD_SRC_XSBMATCH_H
00005 // $Id: XSBQuery_8h-source.html,v 1.2 2001/10/10 20:40:58 sandro Exp $
00006 #include "config.h"
00007 #include "Query.h"
00008 #include <string>
00009 #include "ByteSink.h"
00010 #include "ByteFIFO.h"
00011 class XSBAgent;
00012 class XSBPool;
00013 
00018 class XSBQuery : public Query {
00019       
00020 public:
00021 
00022     // STANDARD MEMBER FUNCTIONS
00023     XSBQuery(XSBAgent& agent, const XSBPool& dataset,
00024          const TripleSource& pattern);
00025     XSBQuery(const XSBQuery& other);
00026     const XSBQuery& operator=(const XSBQuery& other);
00027     bool operator==(const XSBQuery& other) const;
00028     bool operator<(const XSBQuery& other) const;
00029     size_t hash() const;
00030     friend std::ostream& operator<<(std::ostream& s, const XSBQuery& me);
00031     std::ostream& print_to(std::ostream& stream) const; 
00032     virtual ~XSBQuery();       
00033 
00034     // (RE)IMPLEMENTATION OF INHERITED MEMBERS
00035  
00036     virtual bool advanceToFirst();
00037     virtual bool advanceToNext();
00038     virtual bool getResults();
00039     virtual void close();
00040     virtual Triple getFailurePoint();
00041 
00042     // CLASS-SPECIFIC PUBLIC INTERFACE
00043 
00044     void handleValue(int value);
00045 
00046     bool getVarsMatchOnlyVars() { return varsMatchOnlyVars; }
00047     void setVarsMatchOnlyVars(bool newVal) { 
00048     assert (!running);
00049     varsMatchOnlyVars = newVal; 
00050     }
00051 
00052 private:
00053     const TripleSource& pattern;
00054     const XSBPool& dataset;
00055     XSBAgent& agent;
00056     bool open;
00057     bool running;
00058     bool varsMatchOnlyVars;
00059 
00060     // we need a constant order & reference numbering
00061     std::vector<Triple> pv;
00062 
00063     char* fileName;
00064     std::ostream* file;
00065 
00066     std::string runPredicate;
00067 
00068     void writeFile();
00069     void printTriple(std::ostream& out, Triple t, int* maxVar) ;
00070 
00071     int maxVar;
00072     enum { SEARCHING=1, READING_MATCH, READING_FAILURE, EXPECTING_END, ENDED } state ;
00073     enum { MATCH_FOLLOWS=1000, FAILPOINT_FOLLOWS };
00074     int readIndex;
00075 
00076     bool success;
00077     Triple failurePoint;
00078 
00079 
00080 };     
00081 
00082 STANDARD_EXTERNAL(XSBQuery)
00083 
00084 #endif  /* DEV_W3_ORG__2001_BLINDFOLD_SRC_XSBMATCH_H */   // -*-C++-*-
00085 
00086