application.h

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		/// usually happens as the first action in Application::initialize(),
		/// the application's logger is the one specified by the
		/// "application.logger" configuration property. If that property
		/// is not specified, the logger is "Application".
		
	const OptionSet& options() const;
		/// Returns the application's option set.

	static Application& instance();
		/// Returns a reference to the Application singleton.
		///
		/// Throws a NullPointerException if no Application instance exists.

	const Poco::Timestamp& startTime() const;
		/// Returns the application start time (UTC).

	Poco::Timespan uptime() const;
		/// Returns the application uptime.
		
	void stopOptionsProcessing();
		/// If called from an option callback, stops all further
		/// options processing.
		///
		/// If called, the following options on the command line
		/// will not be processed, and required options will not
		/// be checked.
		///
		/// This is useful, for example, if an option for displaying
		/// help information has been encountered and no other things
		/// besides displaying help shall be done.

	const char* name() const;

protected:
	void initialize(Application& self);
		/// Initializes the application and all registered subsystems.
		/// Subsystems are always initialized in the exact same order
		/// in which they have been registered.
		///
		/// Overriding implementations must call the base class implementation.
		
	void uninitialize();
		/// Uninitializes the application and all registered subsystems.
		/// Subsystems are always uninitialized in reverse order in which
		/// they have been initialized. 
		///
		/// Overriding implementations must call the base class implementation.

	void reinitialize(Application& self);
		/// Re-nitializes the application and all registered subsystems.
		/// Subsystems are always reinitialized in the exact same order
		/// in which they have been registered.
		///
		/// Overriding implementations must call the base class implementation.

	virtual void defineOptions(OptionSet& options);
		/// Called before command line processing begins.
		/// If a subclass wants to support command line arguments,
		/// it must override this method.
		/// The default implementation does not define any options itself,
		/// but calls defineOptions() on all registered subsystems.
		///
		/// Overriding implementations should call the base class implementation.

	virtual void handleOption(const std::string& name, const std::string& value);
		/// Called when the option with the given name is encountered
		/// during command line arguments processing.
		///
		/// The default implementation does option validation, bindings
		/// and callback handling.
		///
		/// Overriding implementations must call the base class implementation.

	void setLogger(Poco::Logger& logger);
		/// Sets the logger used by the application.

	virtual int main(const std::vector<std::string>& args);
		/// The application's main logic.
		///
		/// Unprocessed command line arguments are passed in args.
		/// Note that all original command line arguments are available
		/// via the properties application.argc and application.argv[<n>].
		///
		/// Returns an exit code which should be one of the values
		/// from the ExitCode enumeration.

	bool findFile(Poco::Path& path) const;
		/// Searches for the file in path in the application directory.
		///
		/// If path is absolute, the method immediately returns true and
		/// leaves path unchanged.
		///
		/// If path is relative, searches for the file in the application
		/// directory and in all subsequent parent directories.
		/// Returns true and stores the absolute path to the file in
		/// path if the file could be found. Returns false and leaves path
		/// unchanged otherwise.

	void init();
		/// Common initialization code.

	~Application();
		/// Destroys the Application and deletes all registered subsystems.

private:
	void setup();
	void setArgs(int argc, char* argv[]);
	void setArgs(const std::vector<std::string>& args);
	void getApplicationPath(Poco::Path& path) const;
	void processOptions();
	bool findAppConfigFile(const std::string& appName, const std::string& extension, Poco::Path& path) const;

	typedef Poco::AutoPtr<Subsystem> SubsystemPtr;
	typedef std::vector<SubsystemPtr> SubsystemVec;
	typedef Poco::AutoPtr<LayeredConfiguration> ConfigPtr;
	typedef std::vector<std::string> ArgVec;
	
	ConfigPtr       _pConfig;
	SubsystemVec    _subsystems;
	bool            _initialized;
	std::string     _command;
	ArgVec          _args;
	OptionSet       _options;
	bool            _unixOptions;
	Poco::Logger*   _pLogger;
	Poco::Timestamp _startTime;
	bool            _stopOptionsProcessing;

	static Application* _pInstance;
	
	friend class LoggingSubsystem;

	Application(const Application&);
	Application& operator = (const Application&);
};


//
// inlines
//
template <class C> C& Application::getSubsystem() const
{
	for (SubsystemVec::const_iterator it = _subsystems.begin(); it != _subsystems.end(); ++it)
	{
		const Subsystem* pSS(it->get());
		const C* pC = dynamic_cast<const C*>(pSS);
		if (pC) return *const_cast<C*>(pC);
	}
	throw Poco::NotFoundException("The subsystem has not been registered", typeid(C).name());
}


inline bool Application::initialized() const
{
	return _initialized;
}


inline LayeredConfiguration& Application::config() const
{
	return *const_cast<LayeredConfiguration*>(_pConfig.get());
}


inline Poco::Logger& Application::logger() const
{
	poco_check_ptr (_pLogger);
	return *_pLogger;
}


inline const OptionSet& Application::options() const
{
	return _options;
}


inline Application& Application::instance()
{
	poco_check_ptr (_pInstance);
	return *_pInstance;
}


inline const Poco::Timestamp& Application::startTime() const
{
	return _startTime;
}


inline Poco::Timespan Application::uptime() const
{
	Poco::Timestamp now;
	Poco::Timespan uptime = now - _startTime;
	
	return uptime;
}


} } // namespace Poco::Util


//
// Macro to implement main()
//
#if defined(_WIN32) && defined(POCO_WIN32_UTF8) && !defined(POCO_NO_WSTRING)
	#define POCO_APP_MAIN(App) \
	int wmain(int argc, wchar_t** argv)		\
	{										\
		Poco::AutoPtr<App> pApp = new App;	\
		try									\
		{									\
			pApp->init(argc, argv);			\
		}									\
		catch (Poco::Exception& exc)		\
		{									\
			pApp->logger().log(exc);		\
			return Application::EXIT_CONFIG;\
		}									\
		return pApp->run();					\
	}
#else
	#define POCO_APP_MAIN(App) \
	int main(int argc, char** argv)			\
	{										\
		Poco::AutoPtr<App> pApp = new App;	\
		try									\
		{									\
			pApp->init(argc, argv);			\
		}									\
		catch (Poco::Exception& exc)		\
		{									\
			pApp->logger().log(exc);		\
			return Application::EXIT_CONFIG;\
		}									\
		return pApp->run();					\
	}
#endif


#endif // Util_Application_INCLUDED