Oop: encapsulation, inheritance, polymorphism (continued)

Excuse file 1: Bird. h

# Import <Foundation/Foundation. h>

@ Interface bird: nsobject
{
@ Private
Int _ weight;
Nsstring * _ name;
}
-(Void) fly;

@ End

Implementation file 1: Bird. m

# Import "bird. H"

@ Implementation bird
-(Void) fly
{
Nslog (@ "% @", @ "bird is flying! ");
}
@ End

 

Excuse file 2: Sparrow. h

# Import "bird. H"

@ Interface Sparrow: Bird
{
// @ Protected
// @ Public
// @ Private
Nsstring * _ id;
}
@ Property (nonatomic, assign) nsstring * ID;
-(Void) set_id :( nsstring *) ID;
-(Void) print_id;
-(Void) Sing;
@ End

Implementation file 2: Sparrow. m

# Import "Sparrow. H"

@ Implementation sparrow
-(Void) set_id :( nsstring *) ID
{
_ Id = ID;
}
-(Void) print_id
{
Nslog (@ "% @", _ id );
}
-(Void) Sing
{
Nslog (@ "% @", @ "Sparrow is singing! ");
}

@ End

 

Excuse file 3: blacksparrow. h

# Import "Sparrow. H"

@ Interface blacksparrow: sparrow
-(Void) Eat;
-(Void) Sing;
@ End

Implementation file 3: blacksparrow. m

# Import "blacksparrow. H"

@ Implementation blacksparrow
-(Void) fly
{
Nslog (@ "% s" ,__ pretty_function __);
}
-(Void) Eat
{
Nslog (@ "% s" ,__ pretty_function __);
}
-(Void) Sing
{
Nslog (@ "% s" ,__ pretty_function __);
}
@ End

Test File: Main. m

Int main (INT argc, char * argv []) {
@ Autoreleasepool {
Bird * bird = [[Bird alloc] init];
[Bird fly];
Sparrow * sparrow = [[Sparrow alloc] init];
[Sparrow fly];
[Sparrow sing];
[Sparrow set_id: @ "1234"];
[Sparrow print_id];
Bird * bird1 = [[blacksparrow alloc] init];
Blacksparrow * BS = bird1; // forced type conversion
BS. ID = @ "sssss ";

[Bird1 Fly];
[Bird1 eat];
[Bird1 sing];
[Bird1 print_id];
Return uiapplicationmain (argc, argv, nil, nsstringfromclass ([appdelegate class]);
}
}

Oop: encapsulation, inheritance, polymorphism (continued)