Person.h

ragma once

#include "CoreMinimal.h"
#include "UObject/NoExportTypes.h"
#include "Person.generated.h"

UCLASS()
class UNREALINTERFACE_API UPerson : public UObject
{
	GENERATED_BODY()
	
public:
	UPerson();

	FORCEINLINE FString& GetName() { return Name; }
	FORCEINLINE void SetName(const FString& InName) { Name = InName; }

protected:
	UPROPERTY()
	FString Name;
};

Person.cpp

#include "Person.h"

UPerson::UPerson()
{
	Name = TEXT("홍길동");
}

Student.h

#pragma once

#include "CoreMinimal.h"
#include "Person.h"
#include "LessonInterface.h"
#include "Student.generated.h"

UCLASS()
class UNREALINTERFACE_API UStudent : public UPerson, public ILessonInterface
{
	GENERATED_BODY()
	
public:
	UStudent();

	virtual void DoLesson() override;
};

Student.cpp

#include "Student.h"

UStudent::UStudent()
{
	Name = TEXT("이학생");
}

void UStudent::DoLesson()
{
	ILessonInterface::DoLesson();
	UE_LOG(LogTemp, Log, TEXT("%s님은 공부합니다."), *Name);
}

Teacher.h

#pragma once

#include "CoreMinimal.h"
#include "Person.h"
#include "LessonInterface.h"
#include "Teacher.generated.h"

UCLASS()
class UNREALINTERFACE_API UTeacher : public UPerson, public ILessonInterface
{
	GENERATED_BODY()
	
public:
	UTeacher();

	virtual void DoLesson() override;
};

Teacher.cpp

#include "Teacher.h"

UTeacher::UTeacher()
{
	Name = TEXT("이선생");
}

void UTeacher::DoLesson()
{
	//Teacher의 부모는 UPerson이므로 Interface의 함수를 호출하기 위해 Super 키워드를 사용할 수 없음. 
	//그래서 인터페이스 이름을 지정해주고 함수를 호출해줘야함.
	ILessonInterface::DoLesson();
	UE_LOG(LogTemp, Log, TEXT("%s님은 가르칩니다."), *Name);
}

Staff.h