C ++ Unreal 4 - 指针语法

Question

I have doing some starting courses for UE4 Development, and I had a question relating to C++ usage in UE4.

I'm doing a tutorial to create a basic position reporter.

Below is the peek definition of GetOwner() .

FORCEINLINE_DEBUGGABLE class AActor* UActorComponent::GetOwner() const
{


    // During undo/redo the cached owner is unreliable so just used GetTypedOuter
    if (bCanUseCachedOwner)
    {
        checkSlow(OwnerPrivate == GetTypedOuter<AActor>()); // verify cached value is correct
        return OwnerPrivate;
    }
    else
    {
        return GetTypedOuter<AActor>();
    }

Could someone walk me through what the following line is doing exactly?

Is class AActor* grabbing the memory address of AActor? Or is it creating a pointer?

I know the basics of pointers (pointer POINTS to memory address of something, can be dereferenced), just having trouble wrapping my mind around this section.

FORCEINLINE_DEBUGGABLE class AActor* UActorComponent::GetOwner() const

I'm seeing a lot of these in various parts of the UE4 source code, such as in UObjectBase, so I am trying to figure out these all out.

UObjectBase::UObjectBase(UClass* InClass, EObjectFlags InFlags, EInternalObjectFlags InInternalFlags, UObject *InOuter, FName InName)
:   ObjectFlags         (InFlags)
,   InternalIndex       (INDEX_NONE)
,   ClassPrivate        (InClass)
,   OuterPrivate        (InOuter)
{
    check(ClassPrivate);
    // Add to global table.
    AddObject(InName, InInternalFlags);
}

Answer 1

Skipping the debugging macro, the rest of the line

class AActor* UActorComponent::GetOwner() const

is just a complicated way of forward declaring a class type and using that in a return value.

I would write this in two parts:

class AActor;   // forward declare class type

AActor* UActorComponent::GetOwner() const;

A pointer to a class object can be returned (or used as a parameter) without knowing what the class looks like, but it cannot be used otherwise until the full class declaration is seen.