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// ********************************************************************
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//
//
//
// 
// ------------------------------------------------------------
//      GEANT 4 class header file 
//
//
//       ---------------- G4StateManager ----------------
//
// Authors: G.Cosmo, M.Asai - November 1996
//
// -------------------------------------------------------------
//
// Class Description:
//
// Class responsible for handling and updating the running state
// of the Geant4 application during its different phases.
// The class is a singleton, it can be accessed via the public
// method G4StateManager::GetStateManager().
//
// States of Geant4 are defined in G4ApplicationState.

// -------------------------------------------------------------

#ifndef G4StateManager_h
#define G4StateManager_h 1

#include <vector>
#include "G4Types.hh"
#include "G4String.hh"
#include "G4ApplicationState.hh"
#include "G4VStateDependent.hh"
#include "G4VExceptionHandler.hh"

class G4StateManager
{

  public: // with description

    static G4StateManager* GetStateManager();
      // The G4StateManager class is a singleton class and the pointer
      // to the only one existing object can be obtained by this static 
      // method.

   ~G4StateManager();

    const G4ApplicationState& GetCurrentState() const;
      // Returns the current state
    const G4ApplicationState& GetPreviousState() const;
      // Returns the previous state
    G4bool SetNewState(const G4ApplicationState& requestedState);
      // Set Geant4 to a new state.
      // In case the request is irregal, false will be returned
      // and the state of Geant4 will not be changed.
    G4bool SetNewState(const G4ApplicationState& requestedState,
                       const char* msg);
      // Set Geant4 to a new state.
      // In case the request is irregal, false will be returned
      // and the state of Geant4 will not be changed.
      // "msg" is information associating to this state change
    G4bool RegisterDependent(G4VStateDependent* aDependent,G4bool bottom=false);
      // Register a concrete class of G4VStateDependent.
      // Registered concrete classes will be notified via
      // G4VStateDependent::Notify() method when the state of Geant4 changes.
      // False will be returned if registration fails.
    G4bool DeregisterDependent(G4VStateDependent* aDependent);
      // Remove the registration.
      // False will be returned if aDependent has not been registered.
    G4VStateDependent* RemoveDependent(const G4VStateDependent* aDependent);
      // Remove the registration.
      // Removed pointer is returned.
    G4String GetStateString(const G4ApplicationState& aState) const;
      // Utility method which returns a string of the state name.

    inline void SetSuppressAbortion(G4int i);
    inline G4int GetSuppressAbortion() const;
    inline const char* GetMessage() const;
    inline void SetExceptionHandler(G4VExceptionHandler* eh);
    inline G4VExceptionHandler* GetExceptionHandler() const;
    static void SetVerboseLevel(G4int val);

  private:

    G4StateManager();
    G4StateManager(const G4StateManager &right);
    G4StateManager& operator=(const G4StateManager &right);
    G4bool operator==(const G4StateManager &right) const;
    G4bool operator!=(const G4StateManager &right) const;

  private:

    static G4ThreadLocal G4StateManager* theStateManager;
    G4ApplicationState theCurrentState;
    G4ApplicationState thePreviousState;
    std::vector<G4VStateDependent*> theDependentsList;
    G4VStateDependent* theBottomDependent;
    G4int suppressAbortion;
    const char* msgptr;
    G4VExceptionHandler* exceptionHandler;
    static G4int verboseLevel;
};

#include "G4StateManager.icc"

#endif
