<s>
In	O
computing	O
,	O
subject-oriented	B-Application
programming	I-Application
is	O
an	O
object-oriented	B-Language
software	O
paradigm	O
in	O
which	O
the	O
state	O
(	O
fields	O
)	O
and	O
behavior	O
(	O
methods	B-Language
)	O
of	O
objects	O
are	O
not	O
seen	O
as	O
intrinsic	O
to	O
the	O
objects	O
themselves	O
,	O
but	O
are	O
provided	O
by	O
various	O
subjective	O
perceptions	O
(	O
"	O
subjects	O
"	O
)	O
of	O
the	O
objects	O
.	O
</s>
<s>
As	O
illustrated	O
in	O
that	O
paper	O
,	O
an	O
analogy	O
is	O
made	O
with	O
the	O
contrast	O
between	O
the	O
philosophical	O
views	O
of	O
Plato	B-Operating_System
and	O
Kant	O
with	O
respect	O
to	O
the	O
characteristics	O
of	O
"	O
real	O
"	O
objects	O
,	O
but	O
applied	O
to	O
software	O
ones	O
.	O
</s>
<s>
Subject-oriented	B-Application
programming	I-Application
advocates	O
the	O
organization	O
of	O
the	O
classes	O
that	O
describe	O
objects	O
into	O
"	O
subjects	O
"	O
,	O
which	O
may	O
be	O
composed	O
to	O
form	O
larger	O
subjects	O
.	O
</s>
<s>
At	O
points	O
of	O
access	O
to	O
fields	O
or	O
methods	B-Language
,	O
several	O
subjects	O
 '	O
contributions	O
may	O
be	O
composed	O
.	O
</s>
<s>
These	O
points	O
were	O
characterized	O
as	O
the	O
join-points	B-Application
of	O
the	O
subjects	O
.	O
</s>
<s>
For	O
example	O
,	O
if	O
a	O
tree	O
is	O
cut	O
down	O
,	O
the	O
methods	B-Language
involved	O
may	O
need	O
to	O
join	O
behavior	O
in	O
the	O
bird	O
and	O
tax-assessor	O
'	O
s	O
subjects	O
with	O
that	O
of	O
the	O
tree	O
's	O
own	O
.	O
</s>
<s>
The	O
introduction	O
of	O
aspect-oriented	B-Architecture
programming	I-Architecture
in	O
1997	O
raised	O
questions	O
about	O
its	O
relationship	O
to	O
subject-oriented	B-Application
programming	I-Application
,	O
and	O
about	O
the	O
difference	O
between	O
subjects	O
and	O
aspects	O
.	O
</s>
<s>
These	O
questions	O
were	O
unanswered	O
for	O
some	O
time	O
,	O
but	O
were	O
addressed	O
in	O
the	O
patent	O
on	O
Aspect-oriented	B-Architecture
programming	I-Architecture
filed	O
in	O
1999	O
in	O
which	O
two	O
points	O
emerge	O
as	O
characteristic	O
differences	O
from	O
earlier	O
art	O
:	O
</s>
<s>
Hindsight	O
makes	O
it	O
also	O
possible	O
to	O
distinguish	O
aspect-oriented	B-Architecture
programming	I-Architecture
by	O
its	O
introduction	O
and	O
exploitation	O
of	O
the	O
concept	O
of	O
a	O
query-like	O
pointcut	B-Application
to	O
externally	O
impose	O
the	O
join-points	B-Application
used	O
by	O
aspects	O
in	O
general	O
ways	O
.	O
</s>
<s>
In	O
the	O
presentation	O
of	O
subject-oriented	B-Application
programming	I-Application
,	O
the	O
join-points	B-Application
were	O
deliberately	O
restricted	O
to	O
field	O
access	O
and	O
method	B-Language
call	I-Language
on	O
the	O
grounds	O
that	O
those	O
were	O
the	O
points	O
at	O
which	O
well-designed	O
frameworks	O
were	O
designed	O
to	O
admit	O
functional	O
extension	O
.	O
</s>
<s>
The	O
use	O
of	O
externally	O
imposed	O
pointcuts	B-Application
is	O
an	O
important	O
linguistic	O
capability	O
,	O
but	O
remains	O
one	O
of	O
the	O
most	O
controversial	O
features	O
of	O
aspect-oriented	B-Architecture
programming	I-Architecture
.	O
</s>
<s>
To	O
distinguish	O
the	O
common	O
field	O
of	O
interest	O
from	O
Aspect-Oriented	B-Architecture
Programming	I-Architecture
with	O
its	O
particular	O
patent	O
definitions	O
and	O
to	O
emphasize	O
that	O
the	O
compositional	O
technology	O
deals	O
with	O
more	O
than	O
just	O
the	O
coding	O
phase	O
of	O
software	O
development	O
,	O
these	O
technologies	O
were	O
organized	O
together	O
under	O
the	O
term	O
Aspect-Oriented	B-Architecture
Software	I-Architecture
Development	I-Architecture
,	O
and	O
an	O
organization	O
and	O
series	O
on	O
international	O
conferences	O
begun	O
on	O
the	O
subject	O
.	O
</s>
<s>
Like	O
aspect-oriented	B-Architecture
programming	I-Architecture
,	O
subject-oriented	B-Application
programming	I-Application
,	O
composition	O
filters	O
,	O
feature-oriented	B-Application
programming	I-Application
and	O
adaptive	O
methods	B-Language
are	O
considered	O
to	O
be	O
aspect-oriented	B-Architecture
software	I-Architecture
development	I-Architecture
approaches	O
.	O
</s>
<s>
The	O
original	O
formulation	O
of	O
subject-oriented	B-Application
programming	I-Application
deliberately	O
envisioned	O
it	O
as	O
a	O
packaging	O
technology	O
–	O
allowing	O
the	O
space	O
of	O
functions	O
and	O
data	O
types	O
to	O
be	O
extended	O
in	O
either	O
dimension	O
.	O
</s>
<s>
This	O
new	O
concept	O
was	O
implemented	O
for	O
composing	O
Java	B-Language
software	O
,	O
using	O
the	O
name	O
Hyper/J	O
for	O
the	O
tool	O
.	O
</s>
<s>
A	O
research	O
vehicle	O
for	O
Eclipse	B-Application
,	O
called	O
the	O
Concern	O
Manipulation	O
Environment	O
(	O
CME	O
)	O
,	O
has	O
been	O
described	O
in	O
which	O
tools	O
for	O
query	O
,	O
analysis	O
,	O
modelling	O
,	O
and	O
composition	O
are	O
applied	O
to	O
artifacts	O
in	O
any	O
language	O
or	O
representation	O
,	O
through	O
the	O
use	O
of	O
appropriate	O
plug-in	O
adapters	O
to	O
manipulate	O
the	O
representation	O
.	O
</s>
<s>
a	O
query	O
language	O
with	O
unification	O
to	O
identify	O
join	B-Application
points	I-Application
,	O
</s>
<s>
Method	O
dispatch	O
in	O
object	B-Language
oriented	I-Language
programming	I-Language
can	O
be	O
thought	O
of	O
as	O
"	O
two	O
dimensional	O
"	O
in	O
the	O
sense	O
that	O
the	O
code	O
executed	O
depends	O
on	O
both	O
the	O
method	B-Language
name	I-Language
and	O
the	O
object	O
in	O
question	O
.	O
</s>
<s>
This	O
can	O
be	O
contrasted	O
with	O
procedural	O
programming	O
,	O
where	O
a	O
procedure	O
name	O
resolves	O
directly	O
,	O
or	O
one	O
dimensionally	O
,	O
onto	O
a	O
subroutine	O
,	O
and	O
also	O
to	O
subject	B-Application
oriented	I-Application
programming	I-Application
,	O
where	O
the	O
sender	O
or	O
subject	O
is	O
also	O
relevant	O
to	O
dispatch	O
,	O
constituting	O
a	O
third	O
dimension	O
.	O
</s>
