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// $Id:$
//
// Class G4MTRandExponential
// 
// Modified version with MT extensions
// of corresponding CLHEP class RandExponential

// --------------------------------------------------------------------
#ifndef G4MTRandExponential_h
#define G4MTRandExponential_h 1

#include "G4MTHepRandom.hh"

class G4MTRandExponential : public G4MTHepRandom
{

public:

  inline G4MTRandExponential ( CLHEP::HepRandomEngine& anEngine, G4double mean=1.0 );
  inline G4MTRandExponential ( CLHEP::HepRandomEngine* anEngine, G4double mean=1.0 );
  // These constructors should be used to instantiate a G4MTRandExponential
  // distribution object defining a local engine for it.
  // The static generator will be skipped using the non-static methods
  // defined below.
  // If the engine is passed by pointer the corresponding engine object
  // will be deleted by the G4MTRandExponential destructor.
  // If the engine is passed by reference the corresponding engine object
  // will not be deleted by the G4MTRandExponential destructor.

  virtual ~G4MTRandExponential();
  // Destructor

  // Static methods to shoot random values using the static generator

  static  G4double shoot();

  static  G4double shoot( G4double mean );

  static  void shootArray ( const G4int size, G4double* vect,
                            G4double mean=1.0 );

  //  Static methods to shoot random values using a given engine
  //  by-passing the static generator.

  static  inline G4double shoot( CLHEP::HepRandomEngine* anEngine );

  static  inline G4double shoot( CLHEP::HepRandomEngine* anEngine, G4double mean );

  static  void shootArray ( CLHEP::HepRandomEngine* anEngine, const G4int size,
                            G4double* vect, G4double mean=1.0 );

  //  Methods using the localEngine to shoot random values, by-passing
  //  the static generator.

  inline G4double fire();

  inline G4double fire( G4double mean );

  void fireArray ( const G4int size, G4double* vect );
  void fireArray ( const G4int size, G4double* vect, G4double mean );
  
  G4double operator()();
  G4double operator()( G4double mean );

private:

  CLHEP::HepRandomEngine* localEngine;
  G4bool deleteEngine;
  G4double defaultMean;

};

#include "G4MTRandExponential.icc"

#endif