<s>
In	O
aspect-oriented	B-Architecture
programming	I-Architecture
,	O
a	O
pointcut	B-Application
is	O
a	O
set	O
of	O
join	B-Application
points	I-Application
.	O
</s>
<s>
Pointcut	B-Application
specifies	O
where	O
exactly	O
to	O
apply	O
advice	B-Application
,	O
which	O
allows	O
separation	O
of	O
concerns	O
and	O
helps	O
in	O
modularizing	O
business	O
logic	O
.	O
</s>
<s>
Pointcuts	B-Application
are	O
often	O
specified	O
using	O
class	O
names	O
or	O
method	O
names	O
,	O
in	O
some	O
cases	O
using	O
regular	O
expressions	O
that	O
match	O
class	O
or	O
method	O
name	O
.	O
</s>
<s>
Different	O
frameworks	O
support	O
different	O
Pointcut	B-Application
expressions	O
;	O
AspectJ	B-Application
syntax	O
is	O
considered	O
as	O
de	O
facto	O
standard	O
.	O
</s>
<s>
Frameworks	O
are	O
available	O
for	O
various	O
programming	O
languages	O
like	O
Java	B-Language
,	O
Perl	B-Language
,	O
Ruby	B-Language
,	O
and	O
many	O
more	O
which	O
support	O
pointcut	B-Application
.	O
</s>
<s>
Due	O
to	O
limitations	O
in	O
various	O
programming	O
languages	O
,	O
cross-cutting	B-Application
concern	I-Application
has	O
not	O
modularized	O
.	O
</s>
<s>
Cross-cutting	B-Application
concern	I-Application
refers	O
to	O
parts	O
of	O
software	O
that	O
logically	O
belong	O
to	O
one	O
module	O
and	O
affect	O
the	O
whole	O
system	O
:	O
this	O
could	O
be	O
security	O
or	O
logging	O
,	O
for	O
example	O
.	O
</s>
<s>
Aspect-oriented	B-Architecture
programming	I-Architecture
tries	O
to	O
solve	O
these	O
cross	B-Application
cutting	I-Application
concerns	I-Application
by	O
allowing	O
programmers	O
to	O
write	O
modules	O
called	O
aspects	O
,	O
which	O
contain	O
pieces	O
of	O
code	O
executed	O
at	O
particular	O
point	O
.	O
</s>
<s>
The	O
expressions	O
required	O
to	O
select	O
a	O
particular	O
point	O
led	O
to	O
creation	O
of	O
Pointcut	B-Application
Expressions	O
.	O
</s>
<s>
Whenever	O
the	O
program	O
execution	O
reaches	O
one	O
of	O
the	O
join	B-Application
points	I-Application
described	O
in	O
the	O
pointcut	B-Application
,	O
a	O
piece	O
of	O
code	O
associated	O
with	O
the	O
pointcut	B-Application
(	O
called	O
advice	B-Application
)	O
is	O
executed	O
.	O
</s>
<s>
Pointcut	B-Application
permits	O
the	O
addition	O
of	O
aspects	O
to	O
existing	O
software	O
,	O
as	O
well	O
as	O
the	O
design	O
of	O
software	O
with	O
a	O
clear	O
separation	O
of	O
concerns	O
,	O
wherein	O
the	O
programmer	O
weaves	B-Application
(	O
merges	O
)	O
different	O
aspects	O
into	O
a	O
complete	O
application	O
.	O
</s>
<s>
With	O
aspect-oriented	B-Architecture
programming	I-Architecture
,	O
we	O
can	O
apply	O
pointcut	B-Application
to	O
the	O
Modify	O
Database	O
method	O
and	O
have	O
an	O
advice	B-Application
that	O
is	O
called	O
to	O
log	O
the	O
required	O
information	O
.	O
</s>
<s>
Following	O
are	O
some	O
of	O
the	O
important	O
pointcut	B-Application
expressions	O
supported	O
by	O
AspectJ	B-Application
.	O
</s>
<s>
This	O
pointcut	B-Application
matches	O
execution	O
of	O
the	O
User.setPassword	O
method	O
.	O
</s>
<s>
When	O
User.getPassword	O
is	O
called	O
,	O
this	O
pointcut	B-Application
is	O
matched	O
.	O
</s>
<s>
Pointcut	B-Application
will	O
match	O
when	O
the	O
object	O
currently	O
executing	O
is	O
of	O
UserType	O
.	O
</s>
<s>
Pointcut	B-Application
will	O
match	O
when	O
the	O
target	O
object	O
is	O
of	O
UserType	O
.	O
</s>
<s>
Pointcut	B-Application
will	O
match	O
when	O
the	O
code	O
executing	O
belongs	O
to	O
UserType	O
.	O
</s>
<s>
Pointcut	B-Application
languages	O
impact	O
important	O
software	O
properties	O
like	O
evolvability	B-General_Concept
and	O
comprehensibility	O
in	O
a	O
negative	O
way	O
.	O
</s>
<s>
It	O
is	O
also	O
not	O
scalable	B-Architecture
when	O
there	O
are	O
multiple	O
aspects	O
to	O
be	O
applied	O
on	O
the	O
same	O
code	O
and	O
each	O
aspect	O
requires	O
a	O
different	O
refactoring	O
.	O
</s>
<s>
In	O
general	O
every	O
aspect	O
will	O
be	O
tightly	O
coupled	O
with	O
an	O
application	O
’s	O
structure	O
as	O
the	O
pointcuts	B-Application
explicitly	O
contain	O
a	O
method	O
’s	O
signature	O
,	O
so	O
when	O
an	O
application	O
changes	O
the	O
pointcut	B-Application
needs	O
to	O
be	O
changed	O
as	O
well	O
.	O
</s>
