Server Handler -- Prototype Pattern

server_handler__prototype_pattern.cpp

class ICommandHandler {
public:
	virtual void handle(const string &request) = 0;
	virtual ICommandHandler* cone() = 0;
};

class CommandTypeAHandler : public ICommandHandler {
	void handle(const string &request) override {
		// ...
	}

	virtual ICommandHandler* cone() override { 
		return new CommandTypeAHandler();
	}
};

// Same for CommandTypeAHandler ..
// Same for CommandTypeBHandler ..
// Same for CommandTypeCHandler ..
// Same for CommandTypeDHandler ..

class Server {
public:
	void registerCommandHandlers() {
		registerHandler('CommandTypeA', new CommandTypeAHandler());
		registerHandler('CommandTypeB', new CommandTypeBHandler());
		registerHandler('CommandTypeC', new CommandTypeCHandler());
		registerHandler('CommandTypeD', new CommandTypeDHandler());
	}

	void registerHandler(const string &commandId, ICommandHandler *handler) {
		_handlersPrototypes[commandId] = handler;
	}

	void processRequest(const string &request) {
		auto handler = getHandlerForCommandID(parseRequestIDFromRequesteString(request));
		handler->handle(request);
	}

	shared_ptr<ICommandHandler> getHandlerForCommandID(const string &commandId) {
		auto *handler = _handlersPrototypes[commandId]->clone();
		return handler;
	}
	
private:
	map<string, ICommandHandler *> _handlersPrototypes;
};