// EventID.h

#ifndef EventID_H
#define EventID_H

// Class containing the identifier for an event.  This might include
// origin of event (experiment, acquired or simulation, etc) a run
// number and/or date and an event number.
//
// For now, it is simply an integer event number.
//

#include <iosfwd>

class EventID {

private:  // static attributes

  // global event number (last one created)
  static int _global_event_number;

public:  // static methods

  // return the current event number
  static int get_global_event_number() { return _global_event_number; };

private:  // attributes

  // event number
  int _event_number;

  // output stream
  void ostr(std::ostream& stream) const;

public:  // methods

  // default constructor
  // increments the event number
  EventID();

  // constructor from a specified event number
  EventID(int event_number);

  // destructor
  virtual ~EventID();

  // return the event number
  int get_event_number() const { return _event_number; };

  // output stream
  friend std::ostream& operator<<(std::ostream& stream, const EventID& rhs);

};

#endif