Question

I have a base class called BaseClass . Many classes derived from the BaseClass namely SubClass1 , SubClass2 and SubClass3.

@interface  BaseClass: NSObject{
}
-(void)configure;
@end;

@implementation
-(void)configure{
NSLog(@"This needs to log from which sub class this method was called");
}
@end;

The configure method can be called by creating instances of the subclasses or within the implementations of them.

I need to know from which subclass this method was called.

Is this possible?

Answer 1

No. Methods have no way of knowing from which other object’s method they are being called. There’s not even the concept of a caller’s identity. Methods can be called from a C function where there is no caller object at all.

I need to know from which subclass this method was called.

That being said, you probably just want to know of which (derived) class an object is:

NSLog(@"My class: %@", NSStringFromClass([self class]));

2014 Addendum: There’s a gnu extension __builtin_return_address that might be used for this purpose. Mike Ash shows how to use it to extract a callers symbol name (see “Caller Inspection”). I still think that the whole approach is a bit fragile and should only be used for debugging.