Reconstruction/MdcPatRec/TrkBase/include/TrkBase/TrkMomVisitor.h

Go to the documentation of this file.

//--------------------------------------------------------------------------
// File and Version Information:
//
// Description:  TrkMomVisitor is an implementation of the Visitor pattern
//      for use in calculating momenta for different types of
//      trajectories.  (See the book _Design Patterns_ or one of the
//      authors for a definition of the Visitor pattern.)
//
// Environment:
//      Software developed for the BaBar Detector at the SLAC B-Factory.
//
// Author(s): Justin Albert, Steve Schaffner
//
//------------------------------------------------------------------------
#ifndef TRKMOMVISITOR_H
#define TRKMOMVISITOR_H
 
#include "TrkBase/TrkVisitor.h"
 
class TrkSimpTraj;
class HelixTraj;
class TrkCircleTraj;
class NeutTraj;
class TrkDifLineTraj;
 
// Class interface //
class TrkMomVisitor : public TrkVisitor {
 
public:
  TrkMomVisitor( const TrkSimpTraj& );
 
  virtual ~TrkMomVisitor();
 
  // ******************
  // data member access
  // ******************
 
  const HelixTraj*      helix() const { return _ht; }
  const TrkCircleTraj*  circle() const { return _ct; }
  const NeutTraj*       neut() const { return _nt; }
  const TrkDifLineTraj* line() const { return _lt; }
 
  //********************************
  // The visitor functions:
  //********************************
 
  virtual void trkVisitHelixTraj( const HelixTraj* );
  virtual void trkVisitCircleTraj( const TrkCircleTraj* );
  virtual void trkVisitNeutTraj( const NeutTraj* );
  virtual void trkVisitLineTraj( const TrkDifLineTraj* );
 
private:
  const HelixTraj*      _ht;
  const TrkCircleTraj*  _ct;
  const NeutTraj*       _nt;
  const TrkDifLineTraj* _lt;
};
 
#endif