<s>
Cocoa	B-Language
is	O
Apple	O
's	O
native	O
object-oriented	B-Language
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
for	O
its	O
desktop	B-General_Concept
operating	I-General_Concept
system	I-General_Concept
macOS	B-Application
.	O
</s>
<s>
Cocoa	B-Language
consists	O
of	O
the	O
Foundation	B-Operating_System
Kit	I-Operating_System
,	O
Application	B-Operating_System
Kit	I-Operating_System
,	O
and	O
Core	B-Application
Data	I-Application
frameworks	B-Application
,	O
as	O
included	O
by	O
the	O
Cocoa.h	O
header	O
file	O
,	O
and	O
the	O
libraries	O
and	O
frameworks	B-Application
included	O
by	O
those	O
,	O
such	O
as	O
the	O
C	B-Language
standard	O
library	O
and	O
the	O
Objective-C	B-Language
runtime	O
.	O
</s>
<s>
Cocoa	B-Language
applications	B-Application
are	O
typically	O
developed	O
using	O
the	O
development	O
tools	O
provided	O
by	O
Apple	O
,	O
specifically	O
Xcode	B-Operating_System
(	O
formerly	O
Project	B-Operating_System
Builder	I-Operating_System
)	O
and	O
Interface	O
Builder	O
(	O
now	O
part	O
of	O
Xcode	B-Operating_System
)	O
,	O
using	O
the	O
programming	O
languages	O
Objective-C	B-Language
or	O
Swift	B-Application
.	O
</s>
<s>
However	O
,	O
the	O
Cocoa	B-Operating_System
programming	I-Operating_System
environment	O
can	O
be	O
accessed	O
using	O
other	O
tools	O
.	O
</s>
<s>
It	O
is	O
also	O
possible	O
to	O
write	O
Objective-C	B-Language
Cocoa	B-Language
programs	O
in	O
a	O
simple	O
text	B-Application
editor	I-Application
and	O
build	O
it	O
manually	O
with	O
GNU	B-Application
Compiler	I-Application
Collection	I-Application
(	O
GCC	B-Application
)	O
or	O
Clang	B-Application
from	O
the	O
command	O
line	O
or	O
from	O
a	O
makefile	B-Application
.	O
</s>
<s>
For	O
end	O
users	O
,	O
Cocoa	B-Language
applications	B-Application
are	O
those	O
written	O
using	O
the	O
Cocoa	B-Operating_System
programming	I-Operating_System
environment	O
.	O
</s>
<s>
Such	O
applications	B-Application
usually	O
have	O
a	O
familiar	O
look	O
and	O
feel	O
,	O
since	O
the	O
Cocoa	B-Operating_System
programming	I-Operating_System
environment	O
provides	O
a	O
lot	O
of	O
common	O
UI	B-Application
elements	I-Application
(	O
such	O
as	O
buttons	O
,	O
scroll	O
bars	O
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
and	O
automates	O
many	O
aspects	O
of	O
an	O
application	O
to	O
comply	O
with	O
Apple	O
's	O
human	B-Application
interface	I-Application
guidelines	I-Application
.	O
</s>
<s>
For	O
iOS	B-Application
,	O
iPadOS	B-Operating_System
,	O
tvOS	B-Operating_System
,	O
and	O
watchOS	B-Device
,	O
a	O
similar	O
API	B-Application
exists	O
,	O
named	O
Cocoa	B-Operating_System
Touch	I-Operating_System
,	O
which	O
includes	O
gesture	B-General_Concept
recognition	I-General_Concept
,	O
animation	O
,	O
and	O
a	O
different	O
set	O
of	O
graphical	O
control	O
elements	O
.	O
</s>
<s>
It	O
is	O
used	O
in	O
applications	B-Application
for	O
Apple	O
devices	O
such	O
as	O
the	O
iPhone	B-Device
,	O
the	O
iPod	B-Device
Touch	I-Device
,	O
the	O
iPad	B-Device
,	O
the	O
Apple	B-Device
TV	I-Device
,	O
and	O
the	O
Apple	B-Device
Watch	I-Device
.	O
</s>
<s>
Cocoa	B-Language
continues	O
the	O
lineage	O
of	O
several	O
software	B-Architecture
frameworks	I-Architecture
(	O
mainly	O
the	O
App	O
Kit	O
and	O
Foundation	B-Operating_System
Kit	I-Operating_System
)	O
from	O
the	O
NeXTSTEP	B-Application
and	O
OpenStep	B-Operating_System
programming	O
environments	O
developed	O
by	O
NeXT	O
in	O
the	O
1980s	O
and	O
1990s	O
.	O
</s>
<s>
Apple	O
acquired	O
NeXT	O
in	O
December	O
1996	O
,	O
and	O
subsequently	O
went	O
to	O
work	O
on	O
the	O
Rhapsody	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
that	O
was	O
to	O
be	O
the	O
direct	O
successor	O
of	O
OpenStep	B-Operating_System
.	O
</s>
<s>
It	O
was	O
to	O
have	O
had	O
an	O
emulation	O
base	O
for	O
classic	B-Application
Mac	I-Application
OS	I-Application
applications	B-Application
,	O
named	O
Blue	O
Box	O
.	O
</s>
<s>
The	O
OpenStep	B-Operating_System
base	O
of	O
libraries	O
and	O
binary	O
support	O
was	O
termed	O
Yellow	O
Box	O
.	O
</s>
<s>
Rhapsody	B-Operating_System
evolved	O
into	O
Mac	B-Application
OS	I-Application
X	B-Operating_System
,	O
and	O
the	O
Yellow	O
Box	O
became	O
Cocoa	B-Language
.	O
</s>
<s>
Thus	O
,	O
Cocoa	B-Language
classes	O
begin	O
with	O
the	O
letters	O
NS	O
,	O
such	O
as	O
NSString	O
or	O
NSArray	O
.	O
</s>
<s>
These	O
stand	O
for	O
the	O
original	O
proprietary	B-Application
term	O
for	O
the	O
OpenStep	B-Operating_System
framework	O
,	O
NeXTSTEP	B-Application
.	O
</s>
<s>
Much	O
of	O
the	O
work	O
that	O
went	O
into	O
developing	O
OpenStep	B-Operating_System
was	O
applied	O
to	O
developing	O
Mac	B-Application
OS	I-Application
X	B-Operating_System
,	O
Cocoa	B-Language
being	O
the	O
most	O
visible	O
part	O
.	O
</s>
<s>
For	O
example	O
,	O
NeXTSTEP	B-Application
and	O
OpenStep	B-Operating_System
used	O
Display	O
PostScript	B-Language
for	O
on-screen	O
display	O
of	O
text	O
and	O
graphics	O
,	O
while	O
Cocoa	B-Language
depends	O
on	O
Apple	O
's	O
Quartz	B-Operating_System
(	O
which	O
uses	O
the	O
Portable	B-Application
Document	I-Application
Format	I-Application
(	O
PDF	B-Application
)	O
imaging	O
model	O
,	O
but	O
not	O
its	O
underlying	O
technology	O
)	O
.	O
</s>
<s>
Cocoa	B-Language
also	O
has	O
a	O
level	O
of	O
Internet	O
support	O
,	O
including	O
the	O
NSURL	O
and	O
WebKit	B-Language
HTML	B-Language
classes	O
,	O
and	O
others	O
,	O
while	O
OpenStep	B-Operating_System
had	O
only	O
rudimentary	O
support	O
for	O
managed	O
network	O
connections	O
via	O
NSFileHandle	O
classes	O
and	O
Berkeley	B-Protocol
sockets	I-Protocol
.	O
</s>
<s>
The	O
resulting	O
software	B-Architecture
framework	I-Architecture
received	O
the	O
name	O
Cocoa	B-Language
for	O
the	O
sake	O
of	O
expediency	O
,	O
because	O
the	O
name	O
had	O
already	O
been	O
trademarked	O
by	O
Apple	O
.	O
</s>
<s>
For	O
many	O
years	O
before	O
this	O
present	O
use	O
of	O
the	O
name	O
,	O
Apple	O
's	O
Cocoa	B-Language
trademark	O
had	O
originated	O
as	O
the	O
name	O
of	O
a	O
multimedia	O
project	O
design	O
application	O
for	O
children	O
.	O
</s>
<s>
The	O
application	O
was	O
originally	O
developed	O
at	O
the	O
Apple	O
Advanced	O
Technology	O
Group	O
under	O
the	O
name	O
KidSim	B-Language
,	O
and	O
was	O
then	O
renamed	O
and	O
trademarked	O
as	O
"	O
Cocoa	B-Language
"	O
.	O
</s>
<s>
The	O
name	O
,	O
coined	O
by	O
Peter	O
Jensen	O
who	O
was	O
hired	O
to	O
develop	O
Cocoa	B-Language
for	O
Apple	O
,	O
was	O
intended	O
to	O
evoke	O
"	O
Java	O
for	O
kids	O
"	O
,	O
as	O
it	O
ran	O
embedded	O
in	O
web	O
pages	O
.	O
</s>
<s>
The	O
trademark	O
,	O
and	O
thus	O
the	O
name	O
"	O
Cocoa	B-Language
"	O
,	O
was	O
re-used	O
to	O
avoid	O
the	O
delay	O
which	O
would	O
have	O
occurred	O
while	O
registering	O
a	O
new	O
trademark	O
for	O
this	O
software	B-Architecture
framework	I-Architecture
.	O
</s>
<s>
The	O
original	O
"	O
Cocoa	B-Language
"	O
program	O
was	O
discontinued	O
at	O
Apple	O
in	O
one	O
of	O
the	O
rationalizations	O
that	O
followed	O
Steve	O
Jobs	O
's	O
return	O
to	O
Apple	O
.	O
</s>
<s>
It	O
was	O
then	O
licensed	O
to	O
a	O
third	O
party	O
and	O
marketed	O
as	O
Stagecast	B-Language
Creator	I-Language
until	O
2014	O
.	O
</s>
<s>
One	O
feature	O
of	O
the	O
Cocoa	B-Language
environment	O
is	O
its	O
facility	O
for	O
managing	O
dynamically	O
allocated	O
memory	O
.	O
</s>
<s>
Foundation	B-Operating_System
Kit	I-Operating_System
's	O
NSObject	O
class	O
,	O
from	O
which	O
most	O
classes	O
,	O
both	O
vendor	O
and	O
user	O
,	O
are	O
derived	O
,	O
implements	O
a	O
reference	B-General_Concept
counting	I-General_Concept
scheme	O
for	O
memory	O
management	O
.	O
</s>
<s>
When	O
an	O
object	O
's	O
retain	O
count	O
reaches	O
zero	O
,	O
it	O
is	O
deallocated	O
by	O
a	O
procedure	O
similar	O
to	O
a	O
C++	B-Language
destructor	O
.	O
</s>
<s>
Starting	O
with	O
Objective-C	B-Language
2.0	O
,	O
the	O
Objective-C	B-Language
runtime	O
implemented	O
an	O
optional	O
garbage	O
collector	O
,	O
which	O
is	O
now	O
obsolete	O
and	O
deprecated	O
in	O
favor	O
of	O
Automatic	B-Language
Reference	I-Language
Counting	I-Language
(	O
ARC	O
)	O
.	O
</s>
<s>
In	O
this	O
model	O
,	O
the	O
runtime	O
turned	O
Cocoa	B-Language
reference	B-General_Concept
counting	I-General_Concept
operations	O
such	O
as	O
"	O
retain	O
"	O
and	O
"	O
release	O
"	O
into	O
no-ops	B-Language
.	O
</s>
<s>
The	O
garbage	O
collector	O
does	O
not	O
exist	O
on	O
the	O
iOS	B-Application
implementation	O
of	O
Objective-C	B-Language
2.0	O
.	O
</s>
<s>
Garbage	O
collection	O
in	O
Objective-C	B-Language
ran	O
on	O
a	O
low-priority	O
background	O
thread	O
,	O
and	O
can	O
halt	O
on	O
Cocoa	B-Language
's	O
user	O
events	O
,	O
with	O
the	O
intention	O
of	O
keeping	O
the	O
user	O
experience	O
responsive	O
.	O
</s>
<s>
The	O
legacy	O
garbage	O
collector	O
is	O
still	O
available	O
on	O
Mac	B-Application
OS	I-Application
X	B-Operating_System
version	O
10.13	O
,	O
but	O
no	O
Apple-provided	O
applications	B-Application
use	O
it	O
.	O
</s>
<s>
In	O
2011	O
,	O
the	O
LLVM	B-Application
compiler	O
introduced	O
Automatic	B-Language
Reference	I-Language
Counting	I-Language
(	O
ARC	O
)	O
,	O
which	O
replaces	O
the	O
conventional	O
garbage	O
collector	O
by	O
performing	O
static	O
analysis	O
of	O
Objective-C	B-Language
source	O
code	O
and	O
inserting	O
retain	O
and	O
release	O
messages	O
as	O
necessary	O
.	O
</s>
<s>
Cocoa	B-Language
consists	O
of	O
three	O
Objective-C	B-Language
object	O
libraries	O
called	O
frameworks	B-Application
.	O
</s>
<s>
Frameworks	B-Application
are	O
functionally	O
similar	O
to	O
shared	B-Library
libraries	I-Library
,	O
a	O
compiled	O
object	O
that	O
can	O
be	O
dynamically	O
loaded	O
into	O
a	O
program	O
's	O
address	O
space	O
at	O
runtime	O
,	O
but	O
frameworks	B-Application
add	O
associated	O
resources	O
,	O
header	O
files	O
,	O
and	O
documentation	O
.	O
</s>
<s>
The	O
Cocoa	B-Language
frameworks	B-Application
are	O
implemented	O
as	O
a	O
type	O
of	O
bundle	B-Application
,	O
containing	O
the	O
aforementioned	O
items	O
in	O
standard	O
locations	O
.	O
</s>
<s>
Foundation	B-Operating_System
Kit	I-Operating_System
(	O
Foundation	O
)	O
,	O
first	O
appeared	O
in	O
Enterprise	O
Objects	O
Framework	O
on	O
NeXTSTEP	B-Application
3	O
.	O
</s>
<s>
It	O
was	O
developed	O
as	O
part	O
of	O
the	O
OpenStep	B-Operating_System
work	O
,	O
and	O
subsequently	O
became	O
the	O
basis	O
for	O
OpenStep	B-Operating_System
's	O
AppKit	B-Operating_System
when	O
that	O
system	O
was	O
released	O
in	O
1994	O
.	O
</s>
<s>
On	O
macOS	B-Application
,	O
Foundation	O
is	O
based	O
on	O
Core	B-Operating_System
Foundation	I-Operating_System
.	O
</s>
<s>
Foundation	O
is	O
a	O
generic	O
object-oriented	B-Language
library	O
providing	O
string	O
and	O
value	O
manipulation	O
,	O
containers	B-Application
and	O
iteration	B-Algorithm
,	O
distributed	B-Architecture
computing	I-Architecture
,	O
event	B-General_Concept
loops	I-General_Concept
(	O
run	O
loops	O
)	O
,	O
and	O
other	O
functions	O
that	O
are	O
not	O
directly	O
tied	O
to	O
the	O
graphical	B-Application
user	I-Application
interface	I-Application
.	O
</s>
<s>
The	O
"	O
NS	O
"	O
prefix	O
,	O
used	O
for	O
all	O
classes	O
and	O
constants	O
in	O
the	O
framework	O
,	O
comes	O
from	O
Cocoa	B-Language
's	O
OPENSTEP	B-Operating_System
heritage	O
,	O
which	O
was	O
jointly	O
developed	O
by	O
NeXT	O
and	O
Sun	O
Microsystems	O
.	O
</s>
<s>
Application	B-Operating_System
Kit	I-Operating_System
(	O
AppKit	B-Operating_System
)	O
is	O
directly	O
descended	O
from	O
the	O
original	O
NeXTSTEP	B-Application
Application	B-Operating_System
Kit	I-Operating_System
.	O
</s>
<s>
It	O
contains	O
code	O
programs	O
can	O
use	O
to	O
create	O
and	O
interact	O
with	O
graphical	B-Application
user	I-Application
interfaces	I-Application
.	O
</s>
<s>
AppKit	B-Operating_System
is	O
built	O
on	O
top	O
of	O
Foundation	O
,	O
and	O
uses	O
the	O
same	O
NS	O
prefix	O
.	O
</s>
<s>
Core	B-Application
Data	I-Application
is	O
the	O
object	O
persistence	O
framework	O
included	O
with	O
Foundation	O
and	O
Cocoa	B-Language
and	O
found	O
in	O
Cocoa.h.	O
</s>
<s>
A	O
key	O
part	O
of	O
the	O
Cocoa	B-Language
architecture	O
is	O
its	O
comprehensive	O
views	O
model	O
.	O
</s>
<s>
This	O
is	O
organized	O
along	O
conventional	O
lines	O
for	O
an	O
application	B-Application
framework	I-Application
,	O
but	O
is	O
based	O
on	O
the	O
Portable	B-Application
Document	I-Application
Format	I-Application
(	O
PDF	B-Application
)	O
drawing	O
model	O
provided	O
by	O
Quartz	B-Operating_System
.	O
</s>
<s>
This	O
allows	O
creating	O
custom	O
drawing	O
content	O
using	O
PostScript-like	O
drawing	O
commands	O
,	O
which	O
also	O
allows	O
automatic	O
printer	O
support	O
and	O
so	O
forth	O
.	O
</s>
<s>
Since	O
the	O
Cocoa	B-Language
framework	O
manages	O
all	O
the	O
clipping	O
,	O
scrolling	O
,	O
scaling	O
and	O
other	O
chores	O
of	O
drawing	O
graphics	O
,	O
the	O
programmer	O
is	O
freed	O
from	O
implementing	O
basic	O
infrastructure	O
and	O
can	O
concentrate	O
on	O
the	O
unique	O
aspects	O
of	O
an	O
application	O
's	O
content	O
.	O
</s>
<s>
The	O
Smalltalk	B-Application
teams	O
at	O
Xerox	O
PARC	O
eventually	O
settled	O
on	O
a	O
design	O
philosophy	O
that	O
led	O
to	O
easy	O
development	O
and	O
high	O
code	O
reuse	O
.	O
</s>
<s>
Cocoa	B-Language
's	O
design	O
is	O
a	O
fairly	O
,	O
but	O
not	O
absolutely	O
strict	O
application	O
of	O
MVC	O
principles	O
.	O
</s>
<s>
Under	O
OpenStep	B-Operating_System
,	O
most	O
of	O
the	O
classes	O
provided	O
were	O
either	O
high-level	O
View	O
classes	O
(	O
in	O
AppKit	B-Operating_System
)	O
or	O
one	O
of	O
a	O
number	O
of	O
relatively	O
low-level	O
model	O
classes	O
like	O
NSString	O
.	O
</s>
<s>
Compared	O
to	O
similar	O
MVC	O
systems	O
,	O
OpenStep	B-Operating_System
lacked	O
a	O
strong	O
model	O
layer	O
.	O
</s>
<s>
During	O
the	O
transition	O
to	O
Cocoa	B-Language
,	O
the	O
model	O
layer	O
was	O
expanded	O
greatly	O
,	O
introducing	O
a	O
number	O
of	O
pre-rolled	O
classes	O
to	O
provide	O
functionality	O
common	O
to	O
desktop	B-Application
applications	I-Application
.	O
</s>
<s>
In	O
Mac	B-Application
OS	I-Application
X	B-Operating_System
10.3	O
,	O
Apple	O
introduced	O
the	O
NSController	O
family	O
of	O
classes	O
,	O
which	O
provide	O
predefined	O
behavior	O
for	O
the	O
controller	O
layer	O
.	O
</s>
<s>
These	O
classes	O
are	O
considered	O
part	O
of	O
the	O
Cocoa	B-Language
Bindings	B-Application
system	O
,	O
which	O
also	O
makes	O
extensive	O
use	O
of	O
protocols	O
such	O
as	O
Key-Value	O
Observing	O
and	O
Key-Value	O
Binding	O
.	O
</s>
<s>
Bindings	B-Application
allow	O
the	O
developer	O
to	O
focus	O
more	O
on	O
declarative	O
relationships	O
rather	O
than	O
orchestrating	O
fine-grained	O
behavior	O
.	O
</s>
<s>
With	O
the	O
arrival	O
of	O
Mac	B-Application
OS	I-Application
X	B-Operating_System
10.4	O
,	O
Apple	O
extended	O
this	O
foundation	O
further	O
by	O
introducing	O
the	O
Core	B-Application
Data	I-Application
framework	O
,	O
which	O
standardizes	O
change	O
tracking	O
and	O
persistence	O
in	O
the	O
model	O
layer	O
.	O
</s>
<s>
In	O
most	O
object-oriented	B-Language
languages	I-Language
,	O
calls	O
to	O
methods	O
are	O
represented	O
physically	O
by	O
a	O
pointer	O
to	O
the	O
code	O
in	O
memory	O
.	O
</s>
<s>
While	O
Cocoa	B-Language
retains	O
this	O
approach	O
for	O
the	O
most	O
part	O
,	O
Objective-C	B-Language
'	O
s	O
late	O
binding	O
opens	O
up	O
more	O
flexibility	O
.	O
</s>
<s>
Under	O
Objective-C	B-Language
,	O
methods	O
are	O
represented	O
by	O
a	O
selector	O
,	O
a	O
string	O
describing	O
the	O
method	O
to	O
call	O
.	O
</s>
<s>
When	O
a	O
message	O
is	O
sent	O
,	O
the	O
selector	O
is	O
sent	O
into	O
the	O
Objective-C	B-Language
runtime	O
,	O
matched	O
against	O
a	O
list	O
of	O
available	O
methods	O
,	O
and	O
the	O
method	O
's	O
implementation	O
is	O
called	O
.	O
</s>
<s>
By	O
a	O
similar	O
token	O
,	O
Cocoa	B-Language
provides	O
a	O
pervasive	O
data	O
manipulation	O
method	O
called	O
key-value	O
coding	O
(	O
KVC	O
)	O
.	O
</s>
<s>
Also	O
,	O
by	O
extending	O
this	O
system	O
using	O
something	O
Cocoa	B-Language
terms	O
key-value	O
observing	O
(	O
KVO	O
)	O
,	O
automatic	O
support	O
for	O
undo-redo	B-Application
is	O
provided	O
.	O
</s>
<s>
The	O
binding	O
of	O
names	O
before	O
the	O
program	O
is	O
run	O
is	O
called	O
static	O
(	O
early	O
)	O
;	O
bindings	B-Application
performed	O
as	O
the	O
program	O
runs	O
are	O
dynamic	O
(	O
late	O
or	O
virtual	O
)	O
.	O
</s>
<s>
One	O
of	O
the	O
most	O
useful	O
features	O
of	O
Cocoa	B-Language
is	O
the	O
powerful	O
base	O
objects	O
the	O
system	O
supplies	O
.	O
</s>
<s>
As	O
an	O
example	O
,	O
consider	O
the	O
Foundation	O
classes	O
NSString	O
and	O
NSAttributedString	O
,	O
which	O
provide	O
Unicode	O
strings	O
,	O
and	O
the	O
NSText	B-Application
system	O
in	O
AppKit	B-Operating_System
,	O
which	O
allows	O
the	O
programmer	O
to	O
place	O
string	O
objects	O
in	O
the	O
GUI	B-Application
.	O
</s>
<s>
NSText	B-Application
and	O
its	O
related	O
classes	O
are	O
used	O
to	O
display	O
and	O
edit	O
strings	O
.	O
</s>
<s>
The	O
collection	O
of	O
objects	O
involved	O
permit	O
an	O
application	O
to	O
implement	O
anything	O
from	O
a	O
simple	O
single-line	O
text	O
entry	O
field	O
to	O
a	O
complete	O
multi-page	O
,	O
multi-column	O
text	O
layout	O
schema	O
,	O
with	O
full	O
professional	O
typography	B-Application
features	O
such	O
as	O
kerning	O
,	O
ligatures	O
,	O
running	O
text	O
around	O
arbitrary	O
shapes	O
,	O
rotation	O
,	O
full	O
Unicode	O
support	O
,	O
and	O
anti-aliased	B-Algorithm
glyph	B-Application
rendering	O
.	O
</s>
<s>
Unlimited	O
undo/redo	O
support	O
is	O
built	O
in	O
.	O
</s>
<s>
Using	O
only	O
the	O
built-in	O
features	O
,	O
one	O
can	O
write	O
a	O
text	B-Application
editor	I-Application
application	O
in	O
as	O
few	O
as	O
10	O
lines	O
of	O
code	O
.	O
</s>
<s>
When	O
extensions	O
are	O
needed	O
,	O
Cocoa	B-Language
's	O
use	O
of	O
Objective-C	B-Language
makes	O
this	O
a	O
straightforward	O
task	O
.	O
</s>
<s>
Objective-C	B-Language
includes	O
the	O
concept	O
of	O
"	O
,	O
"	O
which	O
allows	O
modifying	O
existing	O
class	O
"	O
in-place	O
"	O
.	O
</s>
<s>
The	O
Cocoa	B-Language
frameworks	B-Application
are	O
written	O
in	O
Objective-C	B-Language
.	O
Java	O
bindings	B-Application
for	O
the	O
Cocoa	B-Language
frameworks	B-Application
(	O
termed	O
the	O
Java	B-Operating_System
bridge	I-Operating_System
)	O
were	O
also	O
made	O
available	O
with	O
the	O
aim	O
of	O
replacing	O
Objective-C	B-Language
with	O
a	O
more	O
popular	O
language	O
but	O
these	O
bindings	B-Application
were	O
unpopular	O
among	O
Cocoa	B-Language
developers	O
and	O
Cocoa	B-Language
's	O
message	O
passing	O
semantics	O
did	O
not	O
translate	O
well	O
to	O
a	O
statically-typed	O
language	O
such	O
as	O
Java	O
.	O
</s>
<s>
Cocoa	B-Language
's	O
need	O
for	O
runtime	O
binding	O
means	O
many	O
of	O
Cocoa	B-Language
's	O
key	O
features	O
are	O
not	O
available	O
with	O
Java	O
.	O
</s>
<s>
In	O
2005	O
,	O
Apple	O
announced	O
that	O
the	O
Java	B-Operating_System
bridge	I-Operating_System
was	O
to	O
be	O
deprecated	O
,	O
meaning	O
that	O
features	O
added	O
to	O
Cocoa	B-Language
in	O
macOS	B-Application
versions	O
later	O
than	O
10.4	O
would	O
not	O
be	O
added	O
to	O
the	O
Cocoa-Java	O
programming	B-Application
interface	I-Application
.	O
</s>
<s>
At	O
Apple	O
Worldwide	O
Developers	O
Conference	O
(	O
WWDC	O
)	O
2014	O
,	O
Apple	O
introduced	O
a	O
new	O
programming	O
language	O
named	O
Swift	B-Application
,	O
which	O
is	O
intended	O
to	O
replace	O
Objective-C	B-Language
.	O
</s>
<s>
Originally	O
,	O
AppleScript	B-Application
Studio	O
could	O
be	O
used	O
to	O
develop	O
simpler	O
Cocoa	B-Language
applications	B-Application
.	O
</s>
<s>
It	O
was	O
replaced	O
with	O
AppleScriptObjC	O
,	O
which	O
allows	O
programming	O
in	O
AppleScript	B-Application
,	O
while	O
using	O
Cocoa	B-Language
frameworks	B-Application
.	O
</s>
<s>
The	O
Cocoa	B-Operating_System
programming	I-Operating_System
environment	O
can	O
be	O
accessed	O
using	O
other	O
tools	O
with	O
the	O
aid	O
of	O
bridge	B-Application
mechanisms	I-Application
such	O
as	O
PasCocoa	B-Operating_System
,	O
PyObjC	B-Operating_System
,	O
CamelBones	B-Operating_System
,	O
RubyCocoa	B-Operating_System
,	O
and	O
a	O
D/Objective	O
-C	O
Bridge	O
.	O
</s>
<s>
Third-party	O
bindings	B-Application
available	O
for	O
other	O
languages	O
include	O
AppleScript	B-Application
,	O
Clozure	B-Application
CL	I-Application
,	O
Monobjc	B-Library
and	O
NObjective	B-Operating_System
(	O
C#	B-Application
)	O
,	O
Cocoa#	B-Language
(	O
CLI	O
)	O
,	O
Cocodao	O
and	O
D/Objective	O
-C	O
Bridge	O
,	O
LispWorks	B-Language
,	O
Object	B-Language
Pascal	I-Language
,	O
CamelBones	B-Operating_System
(	O
Perl	B-Language
)	O
,	O
PyObjC	B-Operating_System
(	O
Python	B-Language
)	O
,	O
FPC	O
PasCocoa	B-Operating_System
(	O
Lazarus	B-Language
and	O
Free	B-Operating_System
Pascal	I-Operating_System
)	O
,	O
RubyCocoa	B-Operating_System
(	O
Ruby	B-Language
)	O
.	O
</s>
<s>
A	O
Ruby	B-Language
language	I-Language
implementation	O
named	O
MacRuby	B-Operating_System
,	O
which	O
removes	O
the	O
need	O
for	O
a	O
bridge	O
mechanism	O
,	O
was	O
formerly	O
developed	O
by	O
Apple	O
,	O
while	O
Nu	B-Application
is	O
a	O
Lisp-like	O
language	O
that	O
uses	O
the	O
Objective-C	B-Language
object	O
model	O
directly	O
,	O
and	O
thus	O
can	O
use	O
the	O
Cocoa	B-Language
frameworks	B-Application
without	O
needing	O
a	O
binding	O
.	O
</s>
<s>
There	O
are	O
also	O
open	O
source	O
implementations	O
of	O
major	O
parts	O
of	O
the	O
Cocoa	B-Language
framework	O
,	O
such	O
as	O
GNUstep	B-Application
and	O
Cocotron	O
,	O
which	O
allow	O
cross-platform	B-Operating_System
Cocoa	B-Language
application	O
development	O
to	O
target	O
other	O
operating	B-General_Concept
systems	I-General_Concept
,	O
such	O
as	O
Microsoft	B-Application
Windows	I-Application
and	O
Linux	B-Application
.	O
</s>
