C++ Pimpl用法

//定义成宏 publicDefine.h
// PIMPL模式声明
#define PIMPL_DEFINE(Classname) \
        const Classname##Impl* GetImpl() const; \
        Classname##Impl* GetImpl(); \
        std::unique_ptr<Classname##Impl> m_pData;

// PIMPL模式实现
#define PIMPL_IMPL(Classname) \
    Classname##Impl* Classname::GetImpl() \
    { \
        return m_pData.get(); \
    } \
    const Classname##Impl* Classname::GetImpl() const \
    { \
        return m_pData.get(); \
    }


  //.h
	class Entity final
	{
	public:
		Entity(int nId, const std::string& entityName);
		~Entity();

		void SetName(const std::string& name);
		std::string GetName() const;

		void SetId(int id);
		int GetId() const;

	private:
		PIMPL_DEFINE(Entity);
	};

/////////////////////////////////
.cpp
class EntityImpl
	{
	public:
		EntityImpl(int nId, const std::string& entityName) : m_nId(nId),
			m_sEntityName(entityName),
			bIsVisile(false)
		{

		}
		int m_nId;
		std::string m_sEntityName;
		bool bIsVisile;
	};

////////////////////////////////
PIMPL_IMPL(Entity);
Entity::Entity(int nId, const std::string& entityName) : m_pData(std::make_unique<EntityImpl>(nId, entityName))
{

}

GCK::Entity::~Entity()
{

}

void Entity::SetName(const std::string& name)
{
	GetImpl()->m_sEntityName = name;
}

std::string Entity::GetName() const
{
	return GetImpl()->m_sEntityName;
}

void Entity::SetId(int id)
{
	GetImpl()->m_nId = id;
}

int Entity::GetId() const
{
	return GetImpl()->m_nId;
}