rtpredicate.h

此文件包含了在linux下实现tpr-tree索引的源代码

// -*- Mode: C++ -*-
//--------------------------------------------------------------------
//      RTpredicate.h
//      -------------
//      Implements the query predicate 
//    
//      Inheritance hierarchy:
//      GiSTobject
//        GiSTpredicate
//          RTpredicate
//
//      TPR-tree - Index for continuously moving objects
//      July 2001 release, Aalborg University
//

#ifndef RTPREDICATE_H
#define RTPREDICATE_H

#include "GiSTpredicate.h"
#include "rtkey.h"

//----------------------------------------------------
enum RToper 
{
  RToverlap,
  RTcontains,
  RTcontained,
  RTEqual
};

//----------------------------------------------------
class RTpredicate : public GiSTpredicate 
{
public:
   RTpredicate(RToper oper, const RTkey& val) : 
              oper(oper), ptr ((GiSTpage) -1) { value = (RTkey*)val.Copy(); }
   RTpredicate(GiSTpage ptr, const RTkey& val) : 
              oper(RTEqual), ptr(ptr) { value = (RTkey*)val.Copy(); }
   RTpredicate(const RTpredicate& p)          : 
              oper(p.oper), ptr(p.ptr) { value = (RTkey*)(p.value->Copy()); }

   GiSTobject* Copy() const { return new RTpredicate(*this); }
   GiSTobjid   IsA () const { return RTPREDICATE_CLASS; }
   int         Consistent(const GiSTentry& entry) const;
   void        SetOper   (RToper op)      { oper = op; }
   void        SetValue  (const RTkey& v) 
   { delete value; value = (RTkey*) v.Copy(); }
   RTkey*      Value () const { return value; }
   RToper      Oper  () const { return oper;  }
   GiSTpage    Ptr   () const { return ptr;   }
   ~RTpredicate() { delete value; }

#ifdef PRINTING_OBJECTS
   void Print(ostream& os) const 
   {
      const char *operstrs[] = { "&&", "^", "||", "=" };
      os << "key " << operstrs[oper] << " " << value;
   }
#endif
  
private:
   GiSTpage  ptr;       // For delete predicates
   RToper    oper;
   RTkey*    value;
};

#endif