R.st.inf.tu-dresden.de/files/teaching/ss14/cbse/... · 9 !!) !! Ó : System.out.println("foo...
34
CBSE, © Prof. Uwe Aßmann 1 44. Aspect-Oriented Programming with Aspect/J Prof. Dr. Uwe Aßmann Technische Universität Dresden Institut für Software- und Multimediatechnik http://st.inf.tu-dresden.de Version 14-0.9, June 14, 2014 1. The Problem of Crosscutting 2. Aspect-Oriented Programming 3. Composition Operators and Point-Cuts 4. AOSD 5. Evaluation as Composition System Prof. U. Aßmann, CBSE 2 Literature ► http://www.eclipse.org/aspectj/ ► http://aosd.net/ ► [KLM+97] G. Kiczales, J. Lamping, A. Mendhekar, C. Maeda, C. Videira Lopes, J.-M. Loingtier, J. Irwin. Aspect-Oriented Programming. 1997 ► R. Laddad. Aspect/J in Action. Manning Publishers. 2003. Book with many details and applications of Aspect/J.
Transcript of R.st.inf.tu-dresden.de/files/teaching/ss14/cbse/... · 9 !!) !! Ó : System.out.println("foo...
-
CBSE
, © P
rof. U
we A
ßman
n 1
44. A
spec
t-Orie
nted
Pro
gram
min
g w
ith A
spec
t/J
Pro
f. D
r. U
we
Aßm
ann
Tech
nisc
he U
nive
rsitä
t Dre
sden
In
stitu
t für
Sof
twar
e- u
nd M
ultim
edia
tech
nik
http
://st
.inf.t
u-dr
esde
n.de
V
ersi
on 1
4-0.
9, J
une
14, 2
014
1.
The
Pro
blem
of C
ross
cutti
ng
2.
Asp
ect-O
rient
ed P
rogr
amm
ing
3.
Com
posi
tion
Ope
rato
rs a
nd
Poi
nt-C
uts
4.
AO
SD
5.
Eva
luat
ion
as C
ompo
sitio
n S
yste
m
Prof.
U. A
ßman
n, CB
SE
2
Lite
ratu
re
►
http
://w
ww
.ecl
ipse
.org
/asp
ectj/
►
http
://ao
sd.n
et/
►
[KLM
+97]
G. K
icza
les,
J. L
ampi
ng, A
. Men
dhek
ar, C
. Mae
da, C
. V
idei
ra L
opes
, J.-M
. Loi
ngtie
r, J.
Irw
in. A
spec
t-Orie
nted
P
rogr
amm
ing.
199
7 ►
R. L
adda
d. A
spec
t/J in
Act
ion.
Man
ning
Pub
lishe
rs. 2
003.
Boo
k w
ith
man
y de
tails
and
app
licat
ions
of A
spec
t/J.
-
Prof.
U. A
ßman
n, CB
SE
3
Oth
er li
tera
ture
• C
. V. L
opes
. Asp
ect-O
rient
ed P
rogr
amm
ing:
An
His
toric
al
Per
spec
tive
(Wha
t's in
a N
ame?
). 20
02
http
://w
ww
.isr.u
ci.e
du/te
ch_r
epor
ts/U
CI-I
SR
-02-
5.pd
f •
G. K
icza
les.
Asp
ect O
rient
ed P
rogr
amm
ing
- Rad
ical
Res
earc
h in
M
odul
arity
. Goo
gle
Tech
Tal
k, 5
7 m
in
http
://vi
deo.
goog
le.c
om/v
ideo
sear
ch?q
=Kic
zale
s •
Jend
rik J
ohan
nes.
Com
pone
nt-B
ased
Mod
el-D
riven
Sof
twar
e D
evel
opm
ent.
PhD
thes
is, D
resd
en U
nive
rsity
of T
echn
olog
y,
Dec
embe
r 201
0.
• Je
ndrik
Joh
anne
s an
d U
we
Aßm
ann.
Con
cern
-bas
ed (d
e)co
mpo
sitio
n of
mod
el-d
riven
sof
twar
e de
velo
pmen
t pro
cess
es. I
n D
. C
. Pet
riu, N
. Rou
quet
te, a
nd O
.Hau
gen,
edi
tors
, MoD
ELS
(2),
volu
me
6395
of L
ectu
re N
otes
in C
ompu
ter S
cien
ce, p
ages
47-
62.
Spr
inge
r, 20
10.
CBSE
, © P
rof. U
we A
ßman
n 4
44.1
The
Pro
blem
of C
ross
cutti
ng
-
Prof.
U. A
ßman
n, CB
SE
5
XML
pars
ing
in o
rg.a
pach
e.to
mca
t
Goo
d m
odul
arity
: Th
e „r
ed“
conc
ern
is h
andl
ed b
y co
de in
one
cla
ss
[Pic
ture
take
n fr
om th
e as
pect
j.org
w
ebsi
te]
Prof.
U. A
ßman
n, CB
SE
6
UR
L pa
ttern
mat
chin
g in
org
.apa
che.
tom
cat
Goo
d m
odul
arity
: Th
e “r
ed”
conc
ern
is h
andl
ed b
y co
de in
two
clas
ses
rela
ted
by in
herit
ance
[Pic
ture
take
n fr
om th
e as
pect
j.org
w
ebsi
te]
-
Prof.
U. A
ßman
n, CB
SE
7
Logg
ing
in o
rg.a
pach
e.to
mca
t
BA
D m
odul
arity
: Th
e co
ncer
n is
han
dled
by
code
that
is s
catte
red
over
alm
ost a
ll cl
asse
s
[Pic
ture
take
n fr
om th
e as
pect
j.org
w
ebsi
te]
Prof.
U. A
ßman
n, CB
SE
8
Com
paris
on
Bad
mod
ular
ity
►
scat
terin
g –
code
add
ress
ing
one
conc
ern
is s
prea
d ar
ound
in
the
code
►
“man
y pl
aces
in th
e co
de a
re
colo
red
with
the
colo
r of t
he
conc
ern”
►
tang
ling
– co
de in
one
regi
on
addr
esse
s m
ultip
le c
once
rns
►
“one
pla
ces
in th
e co
de is
col
ored
w
ith th
e co
lors
of m
any
conc
erns
”
►
Sca
tterin
g an
d ta
nglin
g ap
pear
to
geth
er; t
hey
desc
ribe
diffe
rent
fa
cets
of t
he s
ame
prob
lem
■
redu
ndan
t cod
e ■
diffi
cult
to re
ason
abo
ut
■ di
fficu
lt to
cha
nge
Goo
d M
odul
arity
►
sepa
rate
d –
impl
emen
tatio
n of
a
conc
ern
can
be tr
eate
d as
re
lativ
ely
sepa
rate
ent
ity
►
loca
lized
– im
plem
enta
tion
of
a co
ncer
n ap
pear
s in
one
par
t of
pro
gram
►
mod
ular
– a
bove
+ h
as a
cl
ear,
wel
l def
ined
inte
rface
to
rest
of s
yste
m
-
Prof.
U. A
ßman
n, CB
SE
9
A fi
rst e
xam
ple
for s
catte
ring
►
Eve
ry c
all t
o fo
o is
pre
cede
d by
a lo
g ca
ll (s
catte
ring)
►
Obs
erve
the
gree
n co
lor o
f the
con
cern
“log
ging
”
:
System.out.println("foo called");
Helper.foo(n/3);
:
:
System.out.println("foo called");
Helper.foo(i+j+k);
:
:
System.out.println("foo called");
Helper.foo(x);
:
class Helper {
:
public static void foo(int n) {
…
}
:
}
Prof.
U. A
ßman
n, CB
SE
10
Cla
ssic
Sol
utio
n: R
efac
torin
g of
Sca
ttere
d C
alls
►
Pro
cedu
res
can
mod
ular
ize
this
cas
e (u
nles
s lo
gs u
se c
allin
g co
ntex
t) ►
Sca
ttere
d ca
lls c
an b
e re
fact
ored
into
cal
led
proc
edur
es
:
Helper.foo(n/3);
:
:
Helper.foo(i+j+k);
:
:
Helper.foo(x);
:
class Helper {
:
public static void foo(int n) {
System.out.println("foo called");
…
}
:
}
-
Prof.
U. A
ßman
n, CB
SE
11
A s
econ
d ex
ampl
e of
S&
T
►
all s
ubcl
asse
s ha
ve a
n id
entic
al
met
hod
•
inhe
ritan
ce c
an m
odul
ariz
e th
is
• R
efac
torin
g m
oveU
pMet
hod
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
draw
()
refre
sh()
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
draw
()
refre
sh()
Figu
reEl
emen
t
mov
eBy(
int,
int)
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
draw
()
refre
sh()
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
draw
()
refre
sh()
Figu
reEl
emen
t
mov
eBy(
int,
int)
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
draw
()
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
draw
()
Figu
reEl
emen
t
mov
eBy(
int,
int)
refre
sh()
Prof.
U. A
ßman
n, CB
SE
12
A F
inal
Exa
mpl
e of
S&
T in
the
Impl
emen
tatio
n of
Met
hods
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
draw
()
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
draw
()
Figu
reEl
emen
t
mov
eBy(
int,
int)
refre
sh()
Som
e sc
atte
rings
can
not e
asily
be
refa
ctor
ed.
Exa
mpl
e:
All
impl
emen
tatio
ns o
f th
ese
met
hods
end
with
ca
ll to
: Display.update();
-
Prof.
U. A
ßman
n, CB
SE
13
Nee
ds A
OP
for a
Sol
utio
n
Dis
play
Upd
atin
g
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
draw
()
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
draw
()
Figu
reEl
emen
t
mov
eBy(
int,
int)
refre
sh()
after(): call(void FigureElement+.set*(..))
|| call(void FigureElement.moveBy(int, int))
{
Display.update();
}
after(): call(void FigureElement+.set*(..))
|| call(void FigureElement.moveBy
(int, int))
{
Display.update();
}
Aspe
ct: a
sepa
rate
hype
rslice
s with
conc
ern m
appin
g (cr
ossc
ut re
lation
)
Prof.
U. A
ßman
n, CB
SE
14
Cro
sscu
t Gra
phs
• C
ross
cuts
are
repr
esen
ted
by c
ross
cut g
raph
s be
twee
n co
re a
nd
aspe
ct
• P
oint
cut s
peci
ficat
ions
spe
cify
cro
sscu
t gra
phs
Cor
e A
spec
t
Cro
sscu
t gr
aph
Poi
ntcu
t sp
ecifi
catio
n
-
CBSE
, © P
rof. U
we A
ßman
n 15
44.2
CSS
as
Dec
lara
tive
Asp
ect-O
rient
ed L
angu
age
Cro
sscu
t gra
ph a
s ex
ampl
e be
twee
n co
re s
truct
ure
and
attri
bute
s (c
olor
s)
CBSE
, © P
rof. U
we A
ßman
n 16
44.2
Asp
ect-O
rient
ed P
rogr
amm
ing
-
Prof.
U. A
ßman
n, CB
SE
17
The
AO
P Id
ea
►
Cro
sscu
tting
(sca
tterin
g an
d ta
nglin
g) is
inhe
rent
in c
ompl
ex
syst
ems
■ Th
e “ty
rann
y of
the
dom
inan
t dec
ompo
sitio
n”
■ C
ross
cutti
ng c
once
rns
have
a c
lear
pur
pose
Wha
t ■
have
som
e re
gula
r int
erac
tion
poin
ts
Whe
re
►
AO
P p
ropo
ses
to c
aptu
re c
ross
cutti
ng c
once
rns
expl
icitl
y...
■ in
a m
odul
ar w
ay w
ith c
ore
com
pone
nts
and
aspe
ct c
ompo
nent
s
►
AO
P im
prov
es V
iew
-Bas
ed P
rogr
amm
ing
■ A
OP
als
o re
lies
on o
pen
defin
ition
s. A
cor
e pr
ogra
m is
ope
n in
any
of i
ts jo
in
poin
ts. J
oin
poin
ts s
peci
fy th
e “p
oint
s of
ext
ensi
on”
■ B
eyon
d na
me
mer
ging
(ope
n de
finiti
ons)
, cro
ss-c
uts
(cro
ss-c
uttin
g re
latio
nshi
ps)
can
be d
efin
ed s
uch
that
man
y de
finiti
ons
are
exte
nded
by
an e
xten
sion
■
An
“asp
ect”
is a
gen
eral
ized
con
stru
ctiv
e hy
pers
lice
whi
ch c
an e
xten
d m
any
open
de
finiti
ons,
whi
le a
nor
mal
vie
w u
sual
ly e
xten
ds o
nly
one
open
def
initi
on
Prof.
U. A
ßman
n, CB
SE
18
The
AO
P Id
ea (2
)
►
Asp
ects
are
sep
arat
e, in
depe
nden
t hyp
ersl
ices
, in
whi
ch a
cro
sscu
tting
co
ncer
n m
appi
ng re
late
s fra
gmen
t gro
ups
(adv
ices
) to
conc
erns
►
Wea
ving
des
crib
es th
e co
mpo
sitio
n, e
xten
ding
a c
ore
prog
ram
at j
oin
poin
ts
►
At s
oftw
are
deve
lopm
ent t
ime,
asp
ects
and
cla
sses
are
kep
t as
two,
sep
arat
e di
men
sion
s.
►
At r
un-ti
me,
bot
h di
men
sion
nee
d to
be
com
bine
d in
som
e w
ay fo
r obt
aini
ng th
e fin
al p
rodu
ct.
►
Wea
ving
is n
on-s
ymm
etric
com
posi
tion
(hyp
ersl
ice
com
posi
tion
is
sym
met
ric)
Wea
ving
Aspe
ct cla
sses
(fr
agme
nts)
Base
prog
ram
(core
) Jo
in po
ints
Cros
scut
grap
h(p
ointcu
ts)
-
Prof.
U. A
ßman
n, CB
SE
19
Asp
ects
are
Wov
en b
y In
terp
reta
tion
of th
e C
ross
cut G
raph
s •
Cro
sscu
t gra
phs
are
inte
rpre
ted
to in
sert
advi
ce fr
agm
ents
into
cor
e jo
inpo
ints
Cor
e A
spec
t C
ross
cut
grap
h
Poi
ntcu
t sp
ecifi
catio
n
Pat
ched
Cor
e
Prof.
U. A
ßman
n, CB
SE
20
Cro
sscu
t Gra
phs
in V
iew
-Bas
ed P
rogr
amm
ing
• C
ross
cut g
raph
s in
vie
w-b
ased
pro
gram
min
g ar
e in
ject
ive
(Vie
w c
an
exte
nd o
nly
one
open
def
initi
on, b
ut o
pen
defin
ition
s ca
n be
ex
tend
ed b
y m
any
view
s)
• Th
is s
olve
s ta
nglin
g •
Cor
e po
sitio
ns a
re m
ulti-
colo
red
Cor
e Vi
ew
Cro
sscu
t gr
aph
Poi
ntcu
t sp
ecifi
catio
n
-
Prof.
U. A
ßman
n, CB
SE
21
Asp
ects
allo
w fo
r Gen
eral
Cro
sscu
t Gra
phs
• C
ross
cuts
are
non
-inje
ctiv
e, a
spec
ts c
an e
xten
d se
vera
l ope
n de
finiti
ons
• Th
is s
imul
ates
sca
tterin
g •
Asp
ect f
ragm
ents
(adv
ices
) are
mul
tiply
use
d
Cor
e A
spec
t
Cro
sscu
t gr
aph
Poi
ntcu
t sp
ecifi
catio
n
Prof.
U. A
ßman
n, CB
SE
22
Asp
ectJ
: a W
eave
r for
Jav
a
►
Firs
t pro
duct
ion-
qual
ity A
OP
-tech
nolo
gy
►
Allo
ws
spec
ifyin
g hy
pers
lices
for c
ross
cutti
ng c
once
rns
as s
epar
ate
entit
ies:
Asp
ects
■
Stat
ic jo
in p
oint
s ar
e co
de p
ositi
ons,
hoo
ks, o
pen
for e
xten
sion
■
Dyn
amic
join
poi
nts
are
som
e po
ints
in th
e ex
ecut
ion
trace
of a
n ap
plic
atio
n,
open
for e
xten
sion
■
Poin
tcut
: a s
et o
f log
ical
ly re
late
d jo
in p
oint
s ■
Adv
ice:
a fr
agm
ent w
ith b
ehav
ior t
hat s
houl
d be
com
e ac
tive
whe
neve
r a d
ynam
ic
join
poi
nt is
enc
ount
ered
■
Wea
ving
: a
tech
nolo
gy fo
r brin
ging
asp
ects
and
bas
e co
de to
geth
er
// aspects are hyperslices plus integrated concern mapping
aspect <concern> {
// introductions: fragments added to classes of the core
// advices: fragments for extensions of methods
// pointcuts: concern mapping from advices to
// joinpoints of the core
}
-
Prof.
U. A
ßman
n, CB
SE
23
Exam
ple:
A S
impl
e Fi
gure
Edi
tor
oper
atio
ns th
at m
ove
elem
ents
fact
ory
met
hods
D
ispl
ay
*
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
Figu
re
mak
ePoi
nt(..
) m
akeL
ine(
..)
Figu
reEl
emen
t
mov
eBy(
int,
int)
Prof.
U. A
ßman
n, CB
SE
24
Exam
ple:
A S
impl
e Fi
gure
Edi
tor (
Java
)
class Line implements FigureElement{
private Point p1, p2;
Point getP1() { return p1; }
Point getP2() { return p2; }
void setP1(Point p1) { this.p1 = p1; }
void setP2(Point p2) { this.p2 = p2; }
void moveBy(int dx, int dy) { ... }
}
class Point implements FigureElement {
private int x = 0, y = 0;
int getX() { return x; }
int getY() { return y; }
void setX(int x) { this.x = x; }
void setY(int y) { this.y = y; }
void moveBy(int dx, int dy) { ... }
}
-
Prof.
U. A
ßman
n, CB
SE
25
Dis
play
Upd
atin
g
►
Col
lect
ion
of fi
gure
ele
men
ts
■ th
at m
ove
perio
dica
lly
■ m
ust r
efre
sh th
e di
spla
y as
nee
ded
we
will
ass
ume
just
a
sing
le d
ispl
ay
Prof.
U. A
ßman
n, CB
SE
26
a Li
ne
a Po
int
Asp
ect/J
Dyn
amic
Joi
n Po
ints
(Dyn
amic
H
ooks
)
►
A d
ynam
ic jo
in p
oint
is a
hoo
k (e
xten
sion
poi
nt) i
n th
e ex
ecut
ion
trace
of a
pro
gram
, als
o in
dyn
amic
cal
l gra
ph
retu
rnin
g or
th
row
ing
disp
atch
disp
atch
a m
etho
d ca
ll re
turn
ing
or th
row
ing
a m
etho
d ex
ecut
ion
retu
rnin
g or
thro
win
g a
met
hod
exec
utio
n
line.moveBy(2, 2)
-
Prof.
U. A
ßman
n, CB
SE
27
Dyn
amic
Joi
n Po
int T
erm
inol
ogy
►
The
join
-poi
nt m
odel
of A
spec
t/J d
efin
es s
ever
al ty
pes
of jo
in
poin
ts (j
oin-
poin
t typ
es)
■ m
etho
d &
con
stru
ctor
cal
l ■
met
hod
& c
onst
ruct
or e
xecu
tion
■ fie
ld g
et &
set
■
exce
ptio
n ha
ndle
r exe
cutio
n ■
stat
ic &
dyn
amic
initi
aliz
atio
n a Li
ne
disp
atch
met
hod
call
join
poi
nts
Met
hod
body
ex
ecut
ion
join
poi
nts
Prof.
U. A
ßman
n, CB
SE
28
Join
Poi
nt T
erm
inol
ogy
a Po
int
a Li
ne
all j
oin
poin
ts o
n th
is s
lide
are
with
in th
e co
ntro
l flo
w re
gion
of
this
join
poi
nt
a Po
int
line.moveBy(2, 2)
-
Prof.
U. A
ßman
n, CB
SE
29
Prim
itive
Poi
ntcu
ts
►
A p
oint
cut i
s an
spe
cific
atio
n ad
dres
sing
a s
et o
f joi
n po
ints
that
: ■
can
mat
ch o
r not
mat
ch a
ny g
iven
join
poi
nt a
nd
■ op
tiona
lly, c
an p
ull o
ut s
ome
of th
e va
lues
at t
hat j
oin
poin
t ■
“a m
eans
of i
dent
ifyin
g jo
in p
oint
s”
► E
xam
ple:
call(void Line.setP1(Point))
mat
ches
if th
e jo
in p
oint
is a
met
hod
call
with
this
sig
natu
re
Prof.
U. A
ßman
n, CB
SE
30
Poin
tcut
Com
posi
tion
►
Poi
ntcu
ts a
re lo
gica
l exp
ress
ions
in A
spec
t/J, t
hey
com
pose
like
pr
edic
ates
, usi
ng &
&, |
| and
!
whe
neve
r a L
ine
rece
ives
a
“vo
id s
etP
1(P
oint
)” o
r “vo
id s
etP
2(P
oint
)” m
etho
d ca
ll or
a “v
oid
Line
.set
P2(
Poi
nt)”
cal
l
a “v
oid
Line
.set
P1(
Poi
nt)”
cal
l
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point));
-
Prof.
U. A
ßman
n, CB
SE
31
Use
r-D
efin
ed P
oint
cuts
►
Use
r-de
fined
(nam
ed) p
oint
cuts
can
be
used
in th
e sa
me
way
as
prim
itive
poi
ntcu
ts
pointcut move():
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point));
nam
e pa
ram
eter
s
mor
e on
par
amet
ers
and
how
poi
ntcu
t can
ex
pose
val
ues
at jo
in
poin
ts in
a fe
w s
lides
Prof.
U. A
ßman
n, CB
SE
32
pointcut move():
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point));
after() returning: move() {
<code here runs after each move>
}
Afte
r Adv
ice
►
An
afte
r adv
ice
is a
frag
men
t des
crib
ing
the
actio
n to
take
afte
r co
mpu
tatio
n un
der j
oin
poin
ts
a Li
ne
afte
r adv
ice
runs
“o
n th
e w
ay b
ack
out”
-
Prof.
U. A
ßman
n, CB
SE
33
A S
impl
e A
spec
t
• A
n as
pect
def
ines
a s
peci
al c
lass
col
lect
ing
all f
ragm
ents
rela
ted
to
one
conc
ern
and
whi
ch w
ill c
ross
cut c
ore
clas
ses
• W
ith o
ne o
r sev
eral
adv
ices
(fra
gmen
ts p
lus
com
posi
tion
expr
essi
on)
• W
ith a
t lea
st o
ne p
oint
cut e
xpre
ssin
g th
e cr
ossc
ut g
raph
aspect DisplayUpdating {
pointcut move():
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point));
after() returning: move() {
Display.update();
}
}
Prof.
U. A
ßman
n, CB
SE
34
With
and
With
out A
spec
tJ
■ D
ispl
ay.u
pdat
e ca
lls a
re ta
ngle
d th
roug
h th
e co
de
■ “w
hat i
s go
ing
on” i
s le
ss e
xplic
it
class Line {
private Point p1, p2;
Point getP1() { return p1; }
Point getP2() { return p2; }
void setP1(Point p1) {
this.p1 = p1;
// join point
}
void setP2(Point p2) {
this.p2 = p2;
// join point
}
}
class Line {
private Point p1, p2;
Point getP1() { return p1; }
Point getP2() { return p2; }
void setP1(Point p1) {
this.p1 = p1;
Display.update();
}
void setP2(Point p2) {
this.p2 = p2;
Display.update();
}
}
aspect DisplayUpdating {
pointcut move():
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point));
after() returning: move() {
Display.update();
}
}
Wea
ver
-
Prof.
U. A
ßman
n, CB
SE
35
A m
ulti-
clas
s as
pect
With
poi
ntcu
ts c
uttin
g ac
ross
mul
tiple
cla
sses
aspect DisplayUpdating {
pointcut move():
call(void FigureElement.moveBy(int, int)) ||
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int));
after() returning: move() {
Display.update();
}
}
Prof.
U. A
ßman
n, CB
SE
36
pointcut move(FigureElement figElt):
target(figElt) &&
(call(void FigureElement.moveBy(int, int)) ||
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int)));
after(FigureElement fe) returning: move(fe) {
<fe is bound to the figure element>
} Usi
ng v
alue
s at
join
poi
nts
►
A p
oint
cut c
an e
xplic
itly
expo
se c
erta
in ru
n-tim
e va
lues
in
para
met
ers
►
An
advi
ce c
an u
se th
e ex
pose
d va
lue
P
oint
cut
Par
amet
er
defin
ed a
nd
used
Poi
ntcu
t par
amet
er
advi
ce p
aram
eter
s
-
Prof.
U. A
ßman
n, CB
SE
37
Para
met
ers
of u
ser-
defin
ed p
oint
cut d
esig
nato
r
► V
aria
ble
is b
ound
by
user
-def
ined
poi
ntcu
t dec
lara
tion
■ P
oint
cut s
uppl
ies
valu
e fo
r var
iabl
e ■
Val
ue is
ava
ilabl
e to
all
user
s of
use
r-de
fined
poi
ntcu
t
poin
tcut
par
amet
ers
pointcut move(Line l):
target(l) &&
(call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)));
after(Line line): move(line) {
<line is bound to the line>
}
type
d va
riabl
e in
pla
ce o
f typ
e na
me
Prof.
U. A
ßman
n, CB
SE
38
Para
met
ers
of a
dvic
e
► V
aria
ble
is b
ound
by
advi
ce d
ecla
ratio
n ■
Poi
ntcu
t sup
plie
s va
lue
for v
aria
ble
■ V
alue
is a
vaila
ble
in a
dvic
e bo
dy
pointcut move(Line l):
target(l) &&
(call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)));
after(Line line): move(line) {
<line is bound to the line>
}
Poi
ntcu
t par
amet
er
advi
ce p
aram
eter
s
-
Prof.
U. A
ßman
n, CB
SE
39
Expl
aini
ng p
aram
eter
s…
► Va
lue
is ‘p
ulle
d’
■ rig
ht to
left
acro
ss ‘:
’
le
ft si
de :
right
sid
e ■
from
poi
ntcu
ts to
use
r-de
fined
poi
ntcu
ts
■ fro
m p
oint
cuts
to a
dvic
e, a
nd th
en a
dvic
e bo
dy
pointcut move(Line l):
target(l) &&
(call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)));
after(Line line): move(line) {
<line is bound to the line>
}
Prof.
U. A
ßman
n, CB
SE
40
Join
Poi
nt Q
ualif
ier “
Targ
et”
A jo
in p
oint
qua
lifie
r doe
s tw
o th
ings
: •
expo
ses
info
rmat
ion
from
the
cont
ext o
f the
join
poi
nt (e
.g, t
arge
t ob
ject
of a
mes
sage
) •
test
s a
pred
icat
e on
join
poi
nts
(e.g
., a
dyna
mic
type
test
- an
y jo
in p
oint
at w
hich
targ
et o
bjec
t is
an in
stan
ce o
f typ
e na
me)
target(<type name> | <formal reference>)
target(Point)
target(Line)
target(FigureElement)
“any
join
poi
nt” m
eans
it m
atch
es jo
in p
oint
s of
all
kind
s:
met
hod
& c
onst
ruct
or c
all j
oin
poin
ts
met
hod
& c
onst
ruct
or e
xecu
tion
join
poi
nts
field
get
& s
et jo
in p
oint
s ex
cept
ion
hand
ler e
xecu
tion
join
poi
nts
stat
ic &
dyn
amic
initi
aliz
atio
n jo
in p
oint
s
-
Prof.
U. A
ßman
n, CB
SE
41
pointcut move(FigureElement figElt):
target(figElt) &&
(call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int)));
after(FigureElement fe): move(fe) {
<fe is bound to the figure element>
} Get
ting
targ
et o
bjec
t in
a po
lym
orph
ic p
oint
cut
target(<supertype name>) &&
► do
es n
ot fu
rther
rest
rict t
he jo
in p
oint
s ► do
es p
ick
up th
e ta
rget
obj
ect
Prof.
U. A
ßman
n, CB
SE
42
Con
text
& m
ultip
le c
lass
es
aspect DisplayUpdating {
pointcut move(FigureElement figElt):
target(figElt) &&
(call(void FigureElement.moveBy(int, int)) ||
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int)));
after(FigureElement fe): move(fe) {
Display.update(fe);
}
}
-
Prof.
U. A
ßman
n, CB
SE
43
class Line {
private Point p1, p2;
Point getP1() { return p1; }
Point getP2() { return p2; }
void setP1(Point p1) {
this.p1 = p1;
Display.update(this);
}
void setP2(Point p2) {
this.p2 = p2;
Display.update(this);
}
}
class Point {
private int x = 0, y = 0;
int getX() { return x; }
int getY() { return y; }
void setX(int x) {
this.x = x;
Display.update(this);
}
void setY(int y) {
this.y = y;
Display.update(this);
}
}
With
out A
spec
tJ
►
no lo
cus
of “d
ispl
ay u
pdat
ing”
■
evol
utio
n is
cum
bers
ome
■ ch
ange
s in
all
clas
ses
■ ha
ve to
trac
k &
cha
nge
all c
alle
rs
Prof.
U. A
ßman
n, CB
SE
44
With
Asp
ectJ
►
clea
r dis
play
upd
atin
g m
odul
e ■
all c
hang
es in
sin
gle
aspe
ct
■ ev
olut
ion
is m
odul
ar
aspect DisplayUpdating {
pointcut move(FigureElement figElt):
target(figElt) &&
(call(void FigureElement.moveBy(int, int) ||
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int)));
after(FigureElement fe) returning: move(fe) {
Display.update(fe);
}
}
class Line {
private Point p1, p2;
Point getP1() { return p1; }
Point getP2() { return p2; }
void setP1(Point p1) {
this.p1 = p1;
}
void setP2(Point p2) {
this.p2 = p2;
}
}
class Point {
private int x = 0, y = 0;
int getX() { return x; }
int getY() { return y; }
void setX(int x) {
this.x = x;
}
void setY(int y) {
this.y = y;
}
}
-
Prof.
U. A
ßman
n, CB
SE
45
Asp
ects
Cro
sscu
t Cla
sses
aspe
ct m
odul
arity
cut
s ac
ross
cl
ass
mod
ular
ity
Asp
ect
Dis
play
Upd
atin
g
Dis
play
*
2 Po
int
getX
()
getY
()
setX
(int)
setY
(int)
mov
eBy(
int,
int)
Line
getP
1()
getP
2()
setP
1(P
oint
) se
tP2(
Poi
nt)
mov
eBy(
int,
int)
Figu
re
mak
ePoi
nt(..
) m
akeL
ine(
..)
Figu
reEl
emen
t
mov
eBy(
int,
int) C
BSE,
© P
rof. U
we A
ßman
n 46
44.3
Com
posi
tion
Ope
rato
rs a
nd
Poin
t-Cut
s
-
Prof.
U. A
ßman
n, CB
SE
47
Type
s of
Adv
ice
Com
posi
tion
Ope
rato
rs
►
befo
re
bef
ore
proc
eedi
ng a
t joi
n po
int
►
afte
r ret
urni
ng a
val
ue to
join
poi
nt
►
afte
r thr
owin
g a
thro
wab
le to
join
poi
nt
►
afte
r
retu
rnin
g to
join
poi
nt e
ither
way
►
arou
nd
on
arriv
al a
t joi
n po
int g
ets
expl
icit
c
ontro
l ove
r whe
n an
d if
prog
ram
pro
ceed
s
Prof.
U. A
ßman
n, CB
SE
48
Exam
ple:
Con
trac
t che
ckin
g w
ith A
spec
ts
►
Sim
ple
appl
icat
ion
of b
efor
e/af
ter/a
roun
d co
mpo
sitio
n op
erat
ors
►
pre-
cond
ition
s (a
ssum
ptio
ns)
■ ch
eck
whe
ther
par
amet
er is
val
id
►
post
-con
ditio
ns (g
uara
ntee
s)
■ ch
eck
whe
ther
val
ues
wer
e se
t
►
Inva
riant
s
►
Che
ck c
ondi
tions
that
sho
uld
be tr
ue e
very
whe
re
►
cond
ition
enf
orce
men
t ■
forc
e pa
ram
eter
s to
be
valid
and
con
sist
ent
-
Prof.
U. A
ßman
n, CB
SE
49
Pre-
Con
ditio
n (A
ssum
ptio
n)
usin
g be
fore
adv
ice
aspect PointBoundsPreCondition {
before(int newX):
call(void Point.setX(int)) && args(newX) {
assert(newX >= MIN_X);
assert(newX <= MAX_X);
}
before(int newY):
call(void Point.setY(int)) && args(newY) {
assert(newY >= MIN_Y);
assert(newY <= MAX_Y);
}
private void assert(boolean v) {
if ( !v )
throw new RuntimeException();
}
}
wha
t fol
low
s th
e ‘:’
is
alw
ays
a po
intc
ut –
pr
imiti
ve o
r use
r-de
fined
Prof.
U. A
ßman
n, CB
SE
50
Post
-con
ditio
n
aspect PointBoundsPostCondition {
after(Point p, int newX) returning:
call(void Point.setX(int)) && target(p) && args(newX) {
assert(p.getX() == newX);
}
after(Point p, int newY) returning:
call(void Point.setY(int)) && target(p) && args(newY) {
assert(p.getY() == newY);
}
private void assert(boolean v) {
if ( !v )
throw new RuntimeException();
}
}
usin
g af
ter a
dvic
e
-
Prof.
U. A
ßman
n, CB
SE
51
Con
ditio
n en
forc
emen
t
aspect PointBoundsEnforcement {
void around(int newX):
call(void Point.setX(int)) && args(newX) {
proceed(// before the join point
clip(newX, MIN_X, MAX_X)
);
// after the join point
System.out.println(“after”);
}
void around(int newY):
call(void Point.setY(int)) && args(newY) {
proceed(clip(newY, MIN_Y, MAX_Y));
}
private int clip(int val, int min, int max) {
return Math.max(min, Math.min(max, val));
}
}
usin
g ar
ound
adv
ice
Prof.
U. A
ßman
n, CB
SE
52
Spec
ial M
etho
ds (H
ooks
in A
dvic
es)
►
For e
ach
arou
nd a
dvic
e w
ith th
e si
gnat
ure
<Tr> around(T1 arg1, T2 arg2, …)
► th
ere
is a
spe
cial
met
hod
with
the
sign
atur
e <Tr> proceed(T1, T2, …)
►
avai
labl
e on
ly in
aro
und
advi
ce, m
eani
ng “r
un w
hat w
ould
hav
e ru
n if
this
aro
und
advi
ce h
ad n
ot b
een
defin
ed”
-
Prof.
U. A
ßman
n, CB
SE
53
Prop
erty
-bas
ed c
ross
cutti
ng (“
List
ener
A
spec
ts”)
►
cros
scut
s of
met
hods
with
a c
omm
on p
rope
rty
■ pu
blic
/priv
ate,
retu
rn a
cer
tain
val
ue, i
n a
parti
cula
r pac
kage
►
logg
ing,
deb
uggi
ng, p
rofil
ing
■ lo
g on
ent
ry to
eve
ry p
ublic
met
hod
package
com.xerox.print;
public class C1 {
…
public void foo() {
A.doSomething(…);
…
}
…
}
package
com.xerox.scan;
public class C2 {
…
public int frotz() {
A.doSomething(…);
…
}
public int bar() {
A.doSomething(…);
…
}
…
}
package
com.xerox.copy;
public class C3 {
…
public String s1() {
A.doSomething(…);
…
}
…
}
Prof.
U. A
ßman
n, CB
SE
54
Prop
erty
-bas
ed c
ross
cutti
ng
►
cons
ider
cod
e m
aint
enan
ce
►
anot
her p
rogr
amm
er a
dds
a pu
blic
met
hod
. i.e
. ext
ends
pub
lic in
terfa
ce –
this
cod
e w
ill s
till w
ork
►
anot
her p
rogr
amm
er re
ads
this
cod
e .
“wha
t’s re
ally
goi
ng o
n” is
exp
licit
aspect PublicErrorLogging {
Log log = new Log();
pointcut publicInterface():
call(public * com.xerox..*.*(..));
after() throwing (Error e): publicInterface() {
log.write(e);
}
}
neat
ly c
aptu
res
publ
ic i
nter
face
of
myp
acka
ge
-
Prof.
U. A
ßman
n, CB
SE
55
Wild
card
ing
in p
oint
cuts
target(Point)
target(graphics.geom.Point)
target(graphics.geom.*)
any
type
in g
raph
ics.
geom
target(graphics..*)
an
y ty
pe in
any
sub
-pac
kage
of g
raph
ics
call(void Point.setX(int))
call(public * Point.*(..))
any
publ
ic m
etho
d on
Poi
nt
call(public * *(..))
any
publ
ic m
etho
d on
any
type
call(void Point.getX())
call(void Point.getY())
call(void Point.get*())
call(void get*())
any
gette
r ca
ll(Point.new(int, int))
call(new(..))
any
cons
truct
or
“*” i
s w
ild c
ard
“..” i
s m
ulti-
part
wild
car
d
Prof.
U. A
ßman
n, CB
SE
56
Oth
er P
rimiti
ve P
oint
cuts
this(<type name>)
any
join
poi
nt a
t whi
ch c
urre
ntly
exe
cutin
g ob
ject
is a
n in
stan
ce o
f typ
e na
me
within(<type name>)
any
join
poi
nt a
t whi
ch c
urre
ntly
exe
cutin
g co
de is
con
tain
ed w
ithin
type
na
me
withincode(<method/constructor signature>)
any
join
poi
nt a
t whi
ch c
urre
ntly
exe
cutin
g co
de is
spe
cifie
d m
etho
d or
con
stru
ctor
ge
t(int Point.x)
set(int Point.x)
field
refe
renc
e or
ass
ignm
ent j
oin
poin
ts
-
Prof.
U. A
ßman
n, CB
SE
57
Oth
er P
rimiti
ve P
oint
cuts
execution(void Point.setX(int))
met
hod/
cons
truct
or e
xecu
tion
join
poi
nts
(act
ual r
unni
ng m
etho
d)
initialization(Point)
obje
ct in
itial
izat
ion
join
poi
nts
staticinitialization(Point)
clas
s in
itial
izat
ion
join
poi
nts
(as
the
clas
s is
load
ed)
cflow(pointcut designator)
all j
oin
poin
ts w
ithin
the
dyna
mic
con
trol f
low
of a
ny jo
in p
oint
in
poin
tcut
des
igna
tor
cflowbelow(pointcut designator)
all j
oin
poin
ts w
ithin
the
dyna
mic
con
trol f
low
bel
ow a
ny jo
in p
oint
in
poi
ntcu
t des
igna
tor,
excl
udin
g th
isJo
inP
oint
Prof.
U. A
ßman
n, CB
SE
58
Exam
ple:
Onl
y to
p-le
vel m
oves
aspect DisplayUpdating {
pointcut move(FigureElement fe):
target(fe) &&
(call(void FigureElement.moveBy(int, int)) ||
call(void Line.setP1(Point)) ||
call(void Line.setP2(Point)) ||
call(void Point.setX(int)) ||
call(void Point.setY(int)));
pointcut topLevelMove(FigureElement fe):
move(fe) && !cflowbelow(move(FigureElement));
after(FigureElement fe) returning: topLevelMove(fe) {
Display.update(fe);
}
}
-
Prof.
U. A
ßman
n, CB
SE
59
Asp
ect/J
Intr
oduc
tions
• A
n as
pect
can
intro
duce
new
attr
ibut
es a
nd m
etho
ds to
exi
stin
g cl
asse
s
aspect PointObserving {
private Vector Point.observers = new Vector();
public static void addObserver(Point p, Screen s){
p.observers.add(s); }
public static void removeObserver(Point p, Screen s){
p.observers.remove(s); }
pointcut changes(Point p): target(p) && call(void Point.set*(int));
after(Point p): changes(p) {
Iterator iter = p.observers.iterator();
while ( iter.hasNext() ) {
updateObserver(p, (Screen)iter.next()); }
}
static void updateObserver(Point p, Screen s) {
s.display(p); }
}
Prof.
U. A
ßman
n, CB
SE
60
Oth
er a
ppro
ache
s (1
)
►
http
://w
ww
.aos
d.ne
t/ ►
Asp
ectJ
use
s co
mpi
le-ti
me
byte
code
wea
ving
, ■
but a
lso
inse
rts c
ode
that
mat
ches
dyn
amic
join
poi
nts
(dyn
amic
wea
ving
) ■
supp
orts
wea
ving
asp
ects
to e
xist
ing
*.cl
ass
files
(bas
ed o
n B
CE
L)
►
Asp
ect/J
was
take
n ov
er b
y IB
M a
s pa
rt of
the
Ecl
ipse
pro
ject
: ht
tp://
ww
w.e
clip
se.o
rg/a
spec
tj A
spec
tC+
+ is
an
aspe
ct-o
rien
ted
exte
nsio
n to
the
C+
+ p
rogr
amm
ing
lang
uage
.
Asp
ectJ
is a
sea
mle
ss a
spec
t-or
ient
ed e
xten
sion
to
Java
tha
t en
able
s th
e m
odul
ar
impl
emen
tatio
n of
a w
ide
rang
e of
cro
sscu
ttin
g co
ncer
ns.
A
spec
tWer
kz is
a d
ynam
ic,
light
wei
ght
and
high
-per
form
ant
AO
P/AO
SD
fra
mew
ork
for
Java
.
JAC
is a
Jav
a fr
amew
ork
for
aspe
ct-o
rien
ted
dist
ribu
ted
prog
ram
min
g.
JBos
s-A
OP
is t
he J
ava
AO
P ar
chite
ctur
e us
ed for
the
JBO
SS a
pplic
atio
n se
rver
.
Nan
nin
g is
an
Asp
ect
Orien
ted
Fram
ewor
k fo
r Ja
va b
ased
on
dyna
mic
pro
xies
and
asp
ects
im
plem
ente
d as
ord
inar
y Ja
va-c
lass
es.
-
Prof.
U. A
ßman
n, CB
SE
61
Oth
er a
ppro
ache
s (2
)
Asp
ectR
is a
spec
t-or
ient
ed p
rogr
amm
ing
for
Rub
y th
at a
llow
s yo
u to
wra
p co
de
arou
nd e
xist
ing
met
hods
in y
our
clas
ses.
A
spec
tS is
an
early
prot
otyp
e th
at e
nabl
es a
spec
t-or
ient
ed p
rogr
amm
ing
in t
he
Squ
eak/
Sm
allta
lk e
nviron
men
t.
Cae
sarJ
is a
n as
pect
-orien
ted
prog
ram
min
g la
ngua
ge t
hat
focu
sses
on
mul
ti-vi
ew
deco
mpo
sitio
n an
d as
pect
reu
sabi
lity.
D
emet
erJ
and
DJ
faci
litat
e th
e st
ruct
ure-
shy
enca
psul
atio
n of
tra
vers
al-r
elat
ed
beha
vior
al c
once
rns.
JA
sCo
is a
n as
pect
-orien
ted
prog
ram
min
g la
ngua
ge t
ailo
red
for
com
pone
nt b
ased
so
ftw
are
deve
lopm
ent.
JM
ang
ler
is a
fra
mew
ork
for
load
-tim
e tr
ansf
orm
atio
n of
Jav
a pr
ogra
ms,
whi
ch
supp
orts
con
flict
-fre
e co
mpo
sitio
n of
inde
pend
ently
dev
elop
ed a
spec
ts
(im
plem
ente
d as
JM
angl
er t
rans
form
er c
ompo
nent
s) a
nd t
heir joi
nt a
pplic
atio
n to
ex
istin
g ba
se c
lass
es.
Mix
Juic
e is
an
exte
nsio
n to
Jav
a, b
ased
on
the
differ
ence
-bas
ed m
odul
e m
echa
nism
.
…
CBSE
, © P
rof. U
we A
ßman
n 62
44.4
AO
SD
-
Prof.
U. A
ßman
n, CB
SE
63
Prob
lem
of A
OSD
: Wea
ver P
rolif
erat
ion
• W
ho b
uild
s al
l the
se w
eave
rs, p
oint
cut s
peci
ficat
ion
lang
uage
s,
exte
nsio
n en
gine
s, a
nd te
mpl
ate
expa
nder
s?
• A
nsw
er:
– U
nive
rsal
poi
ntcu
t lan
guag
es
– U
nive
rsal
com
posa
bilit
y ad
d-on
s
Prof.
U. A
ßman
n, CB
SE
64
Uni
vers
al P
oint
cut L
angu
ages
• Th
e sp
ecifi
catio
n of
a p
oint
cut i
s a
grap
h-th
eore
tic p
robl
em, a
nd
does
not
rely
on
the
core
nor
asp
ect l
angu
age
• W
eave
r pro
lifer
atio
n ca
n be
avo
ided
by
univ
ersa
l poi
ntcu
t la
ngua
ges
for s
peci
fyin
g cr
ossc
ut g
raph
s th
at in
terc
onne
ct b
ase
and
aspe
ct in
any
lang
uage
Cor
e A
spec
t
Cro
sscu
t gr
aph
Poi
ntcu
t sp
ecifi
catio
n
-
Prof.
U. A
ßman
n, CB
SE
65
Uni
vers
al P
oint
cut L
angu
ages
• A
poi
ntcu
t lan
guag
e co
nnec
ts n
ames
of t
he c
ore
and
the
aspe
ct
– do
es n
ot k
now
mor
e co
ncep
ts
• It
can
be u
sed
univ
ersa
lly
•
Exa
mpl
e:
– X
path
, can
it b
e us
ed a
s po
intc
ut la
ngua
ge?
– C
an y
ou s
epar
ate
poin
tcut
s fro
m A
spec
t/J a
dvic
es a
nd a
ddre
ss a
dvic
e jo
inpo
ints
? –
Rel
atio
nal a
lgeb
ra, S
QL,
Dat
alog
–
Gra
ph re
writ
ing
– Lo
gic
Prof.
U. A
ßman
n, CB
SE
66
Tow
ards
Asp
ect-O
rient
ed S
yste
m
Dev
elop
men
t (A
OSD
)
►
Asp
ects
are
impo
rtant
in th
e w
hole
life
cycl
e ■
requ
irem
ents
(ear
ly a
spec
ts)
■ an
alys
is
■ de
sign
(mod
el a
spec
ts)
■ im
plem
enta
tion
(cod
e as
pect
s)
■ te
st
►
Asp
ect-a
war
e de
velo
pmen
t use
s cr
ossc
ut g
raph
s an
d th
eir
spec
ifica
tion
lang
uage
s fo
r all
lang
uage
s (m
odel
ing
and
prog
ram
min
g)
►
[Joh
anne
s] s
how
s ho
w to
mak
e cr
ossc
ut g
raph
s fo
r arb
itrar
y la
ngua
ges
►
Asp
ect-a
war
e to
ols
inte
rpre
t cro
sscu
t gra
phs
►
Reu
sew
are
is a
met
awea
ver,
a ge
nera
tor f
or w
eave
rs
-
Prof.
U. A
ßman
n, CB
SE
67
44.5
Eva
luat
ion:
A
spec
ts a
s C
ompo
sitio
n Sy
stem
Component model
Composition technique
Composition language
Sour
ce co
mpon
ents
(core
, asp
ect)
Advic
es us
e fra
gmen
t com
pone
nts
Grey
box c
ompo
nents
(asp
ects
with
advic
es
and i
ntrod
uctio
ns)
Simp
le se
t of c
ompo
sition
oper
ators
Asym
metric
comp
ositio
n (ex
tensio
n)
Cros
scut
grap
h defi
nition
s (wi
th po
intcu
ts)
Expr
essio
n-ba
sed
Prof.
U. A
ßman
n, CB
SE
68
The
End
►
Man
y sl
ides
cou
rtesy
to W
im V
ande
rper
ren,
Vrij
e U
nive
rsite
t Bru
ssel
, an
d th
e A
spec
t/J te
am
