BSE - TU Dresden
38
CBSE, © Prof. Uwe Aßmann 1 11b) Classical Component Systems – CORBA Prof. Dr. Uwe Aßmann Florian Heidenreich Technische Universität Dresden Institut für Software- und Multimediatechnik http://st.inf.tu-dresden.de 11-0.2, Mai 4, 2011 1. Basic mechanisms for modularity, exchangability, adaptation, transparency 2. Composition technique (connections) 1. Dynamic Call 2. Traded Call 3. Evaluation according to our criteria list 4. CORBA Services 5. CORBA Facilities Prof. U. Aßmann, CBSE 2 Obligatory Reading ► ISC, 3.1-3.3 ► Szyperski 2 nd edition, Chap 13 ► http://java.sun.com/javase/6/docs/technotes/guides/idl/ ► http://java.sun.com/developer/technicalArticles/releases/corba/
Transcript of BSE - TU Dresden
CB
SE
, © P
rof.
Uw
e A
ßman
n 1
11b)
Cla
ssic
al C
ompo
nent
Sys
tem
s –
CO
RB
A
Pro
f. D
r. U
we
Aßm
ann
Flor
ian
Hei
denr
eich
Te
chni
sche
Uni
vers
ität D
resd
en
Inst
itut f
ür S
oftw
are-
und
M
ultim
edia
tech
nik
http
://st
.inf.t
u-dr
esde
n.de
11
-0.2
, Mai
4, 2
011
1.
Bas
ic m
echa
nism
s fo
r m
odul
arity
, exc
hang
abili
ty,
adap
tatio
n, tr
ansp
aren
cy
2.
Com
posi
tion
tech
niqu
e (c
onne
ctio
ns)
1.
Dyn
amic
Cal
l 2.
Trad
ed C
all
3.
Eva
luat
ion
acco
rdin
g to
our
cr
iteria
list
4.
CO
RB
A S
ervi
ces
5.
CO
RB
A Fa
cilit
ies
Pro
f. U
. Aßm
ann,
CB
SE
2
Obl
igat
ory
Rea
ding
►
ISC
, 3.1
-3.3
►
Szy
pers
ki 2
nd e
ditio
n, C
hap
13
►
http
://ja
va.s
un.c
om/ja
vase
/6/d
ocs/
tech
note
s/gu
ides
/idl/
►
http
://ja
va.s
un.c
om/d
evel
oper
/tech
nica
lArti
cles
/rele
ases
/cor
ba/
Pro
f. U
. Aßm
ann,
CB
SE
3
Lite
ratu
re
►
R. O
rfali,
D. H
arke
y: C
lient
/Ser
ver p
rogr
amm
ing
with
Jav
a an
d C
orba
. Wile
y&S
ons.
eas
y to
read
. ►
R. O
rfali,
D. H
arke
y, J
. Edw
ards
: Ins
tant
Cor
ba. A
ddis
on-W
esle
y.
►
CO
RB
A. C
omm
unic
atio
ns o
f the
AC
M, O
ct. 1
998.
All
artic
les.
O
verv
iew
on
CO
RB
A 3
.0.
►
CO
RB
A 3
.1 s
peci
ficat
ion:
http
://w
ww
.om
g.or
g/sp
ec/C
OR
BA
/3.1
/ ►
Jens
-Pet
er R
edlic
h, C
OR
BA
2.0
/ P
rakt
isch
e E
infü
hrun
g fü
r C++
und
Ja
va. V
erla
g: A
ddis
on-W
esle
y, 1
996.
ISB
N: 3
-827
3-10
60-1
Pro
f. U
. Aßm
ann,
CB
SE
4
The
CO
RB
A V
isio
n
One
Rep
osito
ry to
regi
ster
them
all,
One
Rep
osito
ry to
find
them
, O
ne R
epos
itory
to s
tart
them
all,
and
with
IIO
P b
ind
them
In
the
land
of C
OR
BA
whe
re th
e ob
ject
s lie
.
(J. S
iege
l, af
ter J
.J.R
. Tol
kien
)
CB
SE
, © P
rof.
Uw
e A
ßman
n 5
11b.
1 B
asic
Mec
hani
sms
Pro
f. U
. Aßm
ann,
CB
SE
6
CO
RB
A
►
Com
mon
Obj
ect R
eque
st B
roke
r Arc
hite
ctur
e®
►
Foun
ding
yea
r of t
he O
MG
(obj
ect m
anag
emen
t gro
up) 1
989
►
Goa
l: pl
ug-a
nd-p
lay
com
pone
nts
ever
ywhe
re
►
Cor
ba 1
.1 1
991
(IDL,
OR
B, B
OA
) ►
OD
MG
-93
(Sta
ndar
d fo
r OO
-dat
abas
es)
►
Cor
ba 2
.0 1
995,
late
r 2.2
and
2.4
►
Cor
ba 3
.0 1
999
Pro
f. U
. Aßm
ann,
CB
SE
7
Ingr
edie
nts
of C
OR
BA
►
Com
pone
nt M
odel
■
Com
pone
nts
are
clas
ses
and
obje
cts,
i.e.
, sim
ilar t
o ob
ject
-orie
nted
sof
twar
e .
In C
OR
BA
3.0
, the
CC
M h
as a
dditi
onal
ly b
een
intro
duce
d
■ C
ompo
nent
s ha
ve m
ore
com
pone
nt s
ecre
ts
. La
ngua
ge in
tero
pera
bilit
y by
uni
form
inte
rface
des
crip
tion
. Lo
catio
n tra
nspa
renc
y .
Nam
e tra
nspa
renc
y .
Tran
spar
ent n
etw
ork
prot
ocol
s ■
Sta
ndar
diza
tion
. C
OR
BA
Ser
vice
s .
CO
RB
A F
acili
ties
n
Hor
izon
tal v
s. v
ertic
al
►
Com
posi
tion
Tech
niqu
es
■ A
dapt
atio
n by
stu
bs a
nd s
kele
tons
■
CO
RB
A M
OF
for m
etam
odel
ling
Pro
f. U
. Aßm
ann,
CB
SE
8
OM
A (O
bjec
t Man
agem
ent A
rchi
tect
ure)
►
A s
oftw
are
bus,
bas
ed o
n th
e M
edia
tor (
Bro
ker)
des
ign
patte
rn
■ C
oupl
ed b
y de
cora
tor-
conn
ecto
rs
Obj
ect R
eque
st B
roke
r
Obj
ect S
ervi
ces
App
licat
ion
Inte
rface
s D
omai
n In
terfa
ces
Com
mon
Fa
cilit
ies
Pro
f. U
. Aßm
ann,
CB
SE
9
Cor
ba’s
Hyd
roce
phal
us
►
Cor
ba is
larg
e ■
Obj
ect R
eque
st B
roke
r – 2
000
page
s of
spe
cific
atio
n ■
Obj
ect S
ervi
ces
– 30
0 pa
ges
■ C
omm
on F
acili
ties
– 15
0 pa
ges
►
Tech
nica
l rea
sons
■
Cle
an d
etai
led
solu
tion
■ S
omet
imes
ove
rkill
►
Soc
iolo
gic
reas
ons
■ O
MG
is la
rge
(ove
r 800
par
tner
s) a
nd h
eter
ogen
ic
■ S
tand
ard
cove
rs a
wid
e ra
ge
►
Ling
uist
ic re
ason
s ■
Tons
of u
nint
uitiv
e 3-
capi
tals
-nam
es (O
MG
, OR
B, I
DL,
…)
Pro
f. U
. Aßm
ann,
CB
SE
10
The
Top
Cla
ss C
OR
BA
::Obj
ect
CO
RB
A::O
bjec
t
get_
impl
emen
tatio
n ge
t_in
terf
ace
is_n
il is
_a
crea
te_r
eque
st
dupl
icat
e re
leas
e ...
.
►
The
clas
s C
OR
BA
::Obj
ect
defin
es a
com
pone
nt m
odel
■
The
clas
s m
ust b
e in
herit
ed to
al
l obj
ects
in th
e ap
plic
atio
n ►
CO
RB
A su
ppor
ts re
flect
ion
and
intro
spec
tion:
■
get_
inte
rface
del
iver
s a
refe
renc
e to
the
entry
in th
e in
terfa
ce re
posi
tory
■
get_
impl
emen
tatio
n a
refe
renc
e to
the
impl
emen
tatio
n ►
Ref
lect
ion
wor
ks b
y th
e in
terfa
ce re
posi
tory
(li
st_i
nitia
l_re
fere
nces
from
the
CO
RB
A::O
RB
inte
rface
).
Pro
f. U
. Aßm
ann,
CB
SE
11
Prob
lem
: Mul
tiple
Inhe
ritan
ce o
f CO
RB
A
Obj
ect
►
CO
RB
A::O
bjec
t inc
lude
s co
de in
to a
cla
ss
►
Man
y la
ngua
ges
only
offe
r onl
y si
ngle
inhe
ritan
ce
■ A
pplic
atio
n su
per c
lass
mus
t be
a de
lega
tee
■ C
ould
be
solv
ed b
y m
ixin
inhe
ritan
ce (m
ixin
laye
rs)
CO
RB
A::O
bjec
t
App
licat
ionC
lass
th
at n
eeds
co
nnec
tion
App
licat
ionC
lass
S
uper
Cla
ss
CO
RB
A::O
bjec
t
App
licat
ionC
lass
th
at n
eeds
co
nnec
tion
App
licat
ionC
lass
S
uper
Cla
ss
CB
SE
, © P
rof.
Uw
e A
ßman
n 12
11b.
2 C
ompo
sitio
n Te
chni
que
of
CO
RB
A
(Bas
ic C
OR
BA
Con
nect
ions
)
Pro
f. U
. Aßm
ann,
CB
SE
13
Bas
ic C
onne
ctio
ns in
CO
RB
A
►
CO
RB
A c
ompo
ses
com
pone
nts
with
con
nect
ions
■
Sta
tic m
etho
d ca
ll w
ith s
tatic
stu
bs a
nd s
kele
tons
.
Loca
l or r
emot
e ■
Pol
ymor
phic
cal
l .
Loca
l or r
emot
e ■
Eve
nt tr
ansm
issi
on
■ C
allb
ack
(sim
plifi
ed O
bser
ver p
atte
rn)
■ D
ynam
ic in
voca
tion
(DII,
requ
est b
roki
ng)
. S
earc
hing
ser
vice
s dy
nam
ical
ly in
the
web
(loc
atio
n tra
nspa
renc
y of
a s
ervi
ce)
■ Tr
adin
g .
Find
ser
vice
s in
a y
ello
w p
ages
ser
vice
, bas
ed o
n pr
oper
ties
Pro
f. U
. Aßm
ann,
CB
SE
14
Stat
ic C
OR
BA
Cal
l
►
Adv
anta
ge: m
etho
ds o
f the
par
ticip
ants
are
sta
tical
ly k
now
n
■ In
dire
ct c
all b
y st
ub a
nd s
kele
tons
, with
out i
nvol
vem
ent o
f an
OR
B
■ S
uppo
rts d
istri
butio
n (e
xcha
nge
of lo
cal c
all i
n on
e ad
dres
s sp
ace
to re
mot
e ca
ll is
ve
ry e
asy)
.
Inhe
rit fr
om C
OR
BA
cla
ss
. W
rite
an ID
L sp
ec
■ N
o se
arch
for s
ervi
ce o
bjec
ts, r
athe
r fas
t ■
Bet
ter t
ype
chec
k, s
ince
the
com
pile
r kno
ws
the
invo
lved
type
s
►
The
call
goes
thro
ugh
the
serv
er o
bjec
t ada
pter
(ser
ver d
ecor
ator
) ■
Bas
ic (s
erve
r) o
bjec
t ada
pter
(BO
A)
■ P
orta
ble
(ser
ver)
obj
ect a
dapt
er (P
OA
) ■
This
hid
es th
e w
heth
er th
e se
rver
is tr
ansi
ent o
r per
sist
ent
Pro
f. U
. Aßm
ann,
CB
SE
15
Bas
ic O
bjec
t Ada
pter
BO
A
►
The
BO
A h
ides
■
Life
tim
e of
the
serv
er o
bjec
t (a
ctiv
atio
n: s
tart,
sto
p)
■ P
ersi
sten
cy
►
The
BO
A is
impl
emen
ted
in
ever
y O
RB
, for
min
imal
ser
vice
pr
ovis
ion
►
The
BO
A m
aint
ains
an
impl
emen
tatio
n re
posi
tory
(c
ompo
nent
regi
stry
) ►
It su
ppor
ts n
on-o
bjec
t-orie
nted
co
de
►
The
BO
A is
a re
al a
dapt
er (n
o de
cora
tor)
CO
RB
A::B
OA
crea
te
get_
id
disp
ose
set_
exce
ptio
n im
pl_i
s_re
ady
obj_
is_r
eady
ch
ange
_im
plem
enta
tion
deac
tivat
e_im
pl
deac
tivat
e_ob
j
Pro
f. U
. Aßm
ann,
CB
SE
16
Serv
er S
ite
Bas
ic O
bjec
t Ada
pter
B
OA
IDL
Ske
leto
n
Net
wor
k
Ser
ver /
Obj
ect I
mpl
emen
tatio
n
deac
tivat
e_ob
j de
activ
ate_
impl
im
pl_i
s_re
ady
obje
ct_i
s_re
ady
upca
lls cr
eate
get_
id
Pro
f. U
. Aßm
ann,
CB
SE
17
Obj
ect A
ctiv
atio
n on
the
Serv
er th
roug
h a
BO
A
Serv
er
obje
ct1
obje
ct2
CO
RB
A::B
OA
crea
te
get_
id
obj_
is_r
eady
obj_
is_r
eady
im
pl_i
s_re
ady
deac
tivat
e_ob
j
deac
tivat
e_ob
j
deac
tivat
e_im
pl
Pro
f. U
. Aßm
ann,
CB
SE
18
Port
able
Obj
ect A
dapt
er P
OA
►
The
PO
A is
a e
volu
tion
of th
e B
OA
in C
OR
BA
3.0
■ O
ne p
er s
erve
r, se
rvin
g m
any
obje
cts
■ N
este
d P
OA
s po
ssib
le, w
ith n
este
d na
me
spac
es
►
Use
r pol
icie
s fo
r obj
ect
man
agem
ent
■ U
ser-
writ
ten
inst
ance
man
ager
s fo
r m
anag
emen
t of o
bjec
t ins
tanc
es
CO
RB
A::P
OA
crea
te_P
OA
find_
POA
crea
te_r
efer
ence
di
spos
e se
t_ex
cept
ion
impl
_is_
read
y ob
j_is
_rea
dy
chan
ge_i
mpl
emen
tatio
n ac
tivat
e_ob
ject
de
activ
ate_
obje
ct
Pro
f. U
. Aßm
ann,
CB
SE
19
Obj
ect A
dapt
ers
Supp
ort D
iffer
ent S
erve
r Life
-Ti
me
Mod
els
►
Com
mon
ser
ver p
roce
ss (s
hare
d se
rver
) ■
Sev
eral
obj
ects
resi
de in
one
pro
cess
on
the
serv
er; t
he B
OA
initi
aliz
es th
em a
s th
read
s w
ith c
omm
on a
ddre
ss s
pace
(com
mon
apa
rtmen
t)
. de
activ
ate_
impl
, im
pl_i
s_re
ady,
obj
_is_
read
y ar
e m
appe
d di
rect
ly to
thre
ad
func
tions
►
Sepa
rate
ser
ver p
roce
ss (u
nsha
red
serv
er)
■ Fo
r eve
ry o
bjec
t an
own
proc
ess
►
Serv
er-p
er-r
eque
st (s
essi
on s
erve
r)
■ E
very
requ
est g
ener
ates
a n
ew p
roce
ss
■ S
imila
r to
Ses
sion
EJB
►
Pers
iste
nt s
erve
r ■
Ano
ther
app
licat
ion
stor
es th
e ob
ject
s (e
.g.,
a da
ta b
ase)
.
■ Th
e B
OA
pas
ses
on th
e qu
erie
s
■ S
imila
r to
Ent
ity B
ean
Pro
f. U
. Aßm
ann,
CB
SE
20
Cal
lbac
k C
onne
ctor
s w
ith th
e C
allb
ack
Serv
ice
►
The
Cal
lbac
k pa
ttern
is a
sim
plifi
ed O
bser
ver p
atte
rn
■ R
egis
tratio
n an
d no
tific
atio
n, b
ut n
ot s
tatu
s up
date
►
Cal
lbac
k fu
nctio
n re
gist
ratio
n ■
Reg
iste
r a p
roce
dure
var
iabl
e, a
clo
sure
(pro
cedu
re v
aria
ble
with
arg
umen
ts),
or a
re
fere
nce
to a
n ob
ject
at t
he s
ubje
ct, t
he s
erve
r
►
Cal
lbac
k w
orks
for a
ll la
ngua
ges,
not
onl
y ob
ject
-orie
nted
one
s
Clie
nt
Ser
ver
(sub
ject
) C
lient
2
regi
ster
Cal
lbac
k()
riseE
vent
()
callC
allb
ack(
)
retu
rn()
sign
al()
Pro
f. U
. Aßm
ann,
CB
SE
21
Even
t Con
nect
ions
►
Mos
t fle
xibl
e w
ay o
f com
mun
icat
ion
(als
o ca
lled
mes
sage
s)
■ A
sync
hron
ous
com
mun
icat
ion
■ W
orks
for e
very
CO
RB
A la
ngua
ge
►
Rec
eive
r mod
els
■ U
nica
st: o
ne re
ceiv
er
■ M
ultic
ast:
man
y re
ceiv
ers
■ D
ynam
ical
ly v
aryi
ng re
ceiv
ers
►
Push
mod
el: P
ushC
onsu
mer
/Pus
hSup
plie
r: ob
ject
del
iver
s ev
ent w
ith p
ush,
ev
ent i
s sh
ippe
d au
tom
atic
ally
►
Pull
mod
el: P
ullS
uppl
ier/P
ullC
onsu
mer
: ob
ject
wai
ts fo
r eve
nt w
ith p
ull
■ S
ynch
rono
us o
r asy
nchr
onou
s ■
Unt
yped
gen
eric
eve
nts,
or t
yped
by
IDL
►
Even
t cha
nnel
s as
inte
rmed
iate
buf
fers
■
Cha
nnel
s bu
ffer,
filte
r, an
d m
ap o
f pul
l to
push
■
Adv
anta
ge:
. A
sync
hron
ous
Wor
king
in th
e W
eb (w
ith II
OP
and
dyn
amic
Cal
l) .
Atta
chm
ent o
f leg
acy
syst
ems
inte
rest
ing
for u
ser i
nter
face
s, n
etw
ork
com
putin
g et
c.
■ D
isad
vant
age:
Ver
y ge
nera
l int
erfa
ce
CB
SE
, © P
rof.
Uw
e A
ßman
n 22
11b.
2.1
Dyn
amic
Cal
l Con
nect
or
(Req
uest
Bro
king
)
Pro
f. U
. Aßm
ann,
CB
SE
23
Dyn
amic
Cal
l Con
nect
or (R
eque
st B
roki
ng)
►
CO
RB
A d
ynam
ic c
all i
s a
sym
bolic
cal
l, i.e
., a
refle
ctiv
e ca
ll w
ith a
sy
mbo
lic n
ame
and
argu
men
ts
■ W
ithou
t kno
win
g th
at th
e se
rvic
e ex
ists
■
Ser
vice
s ca
n be
dyn
amic
ally
exc
hang
ed,
brou
ght i
nto
the
play
a p
oste
riori
■
With
out r
ecom
pila
tion
of c
lient
s, n
or re
gene
ratio
n of
stu
bs
■ B
indi
ng o
f nam
es to
adr
esse
s is
dyn
amic
►
Req
uire
s de
scrip
tions
of s
eman
tics
of s
ervi
ce c
ompo
nent
s ■
For i
dent
ifica
tion
of s
ervi
ces
. M
etad
ata
(des
crip
tive
data
): ca
talo
gues
of c
ompo
nent
s (in
terfa
ce re
posi
tory
, im
plem
enta
tion
repo
sito
ry)
. P
rope
rty s
ervi
ce (l
ater
)
►
and
a m
edia
tor,
that
look
s fo
r ser
vice
s: th
e O
RB
Pro
f. U
. Aßm
ann,
CB
SE
24
Obj
ect R
eque
st B
roke
r (O
RB
)
►
For a
dyn
amic
cal
l, th
e O
RB
mus
t be
invo
lved
►
The
OR
B is
a m
edia
tor (
desi
gn
patte
rn) b
etw
een
clie
nt a
nd s
erve
r ►
Hid
es th
e th
e en
viro
nmen
t fro
m c
lient
s ►
Can
talk
to o
ther
OR
Bs,
als
o on
the
web
CO
RB
A::O
RB
init
obje
ct_t
o_st
ring
strin
g_to
_obj
ect
BO
A_i
nit
list_
initi
al_s
ervi
ces
reso
lve_
initi
al_r
efer
ence
s ge
t_de
faul
t_co
ntex
t cr
eate
_env
ironm
ent
....
Pro
f. U
. Aßm
ann,
CB
SE
25
OR
B A
ctiv
atio
n
Clie
nt ob
ject
CO
RB
A O
RB
OR
B_i
nit
BO
A_i
nit
list_
initi
al_s
ervi
ces
reso
lve_
initi
al_r
efer
ence
s
Del
iver
s se
rvic
e na
mes
(as
st
rings
) D
eliv
ers
obje
ct re
fere
nces
to
ser
ver o
bjec
ts fr
om s
ervi
ce
nam
es
Initi
aliz
es th
e se
rver
BO
A
Initi
aliz
es th
e m
edia
tor
Pro
f. U
. Aßm
ann,
CB
SE
26
Req
uest
ing
a Se
rvic
e vi
a th
e O
RB
►
Ref
lect
ive
calls
■
Bui
ldin
g a
call
obje
ct (R
eque
st)
■ A
ddin
g ar
gum
ents
■
Invo
king
■
Pol
ling,
read
ing
CO
RB
A::O
RB
// dy
nam
ic c
all
crea
te_l
ist
crea
te_o
pera
tion_
list
add_
item
ad
d_va
lue
invo
ke
poll_
resp
onse
se
nd
get_
resp
onse
de
lete
...
.
Pro
f. U
. Aßm
ann,
CB
SE
27
Prot
ocol
of D
ynam
ic C
all (
DII)
<<<<
<
Serv
er ob
ject
Nam
ing
Con
text
get_
inte
rface
reso
lve
crea
te_l
ist
Clie
nt ob
ject
Ope
ratio
nDef
OR
B
add_
valu
e
add_
item
_req
uest in
voke
dele
te Fr
ee
Req
uest
argu
men
ts
Pro
f. U
. Aßm
ann,
CB
SE
28
Exam
ple
Dyn
amic
Cal
l in
C++
// W
ow
, a c
om
ple
x p
roto
co
l!!
CO
RB
A::
OR
B_p
tr o
rb;
ma
in(i
nt
arg
c, c
ha
r* a
rgv[
]) {
o
rb=
CO
RB
A::
OR
B_i
nit
(arg
c,a
rgv,
OR
BID
);
// a
lte
rnat
ive
de
scri
pti
on
of
serv
ice
C
osN
am
ing
::N
am
ing
Co
nte
xt_p
tr n
am
ing
=
Co
sNa
min
g::
Na
min
gC
on
text
::_n
arr
ow
(
::
reso
lve
_in
itia
l_re
fere
nc
es
(“N
am
eS
erv
ice
”));
C
OR
BA
::O
bje
ct_
ptr
ob
j;
try
{
ob
j= n
am
ing
->re
solv
e(m
k_n
am
e("
dii_
smp
l"))
; }
cat
ch (
CO
RB
A::
Exc
ep
tio
n)
{
ce
rr <
< "
no
t re
gis
tere
d"
<<
en
dl;
exi
t(1
); }
//
co
nst
ruc
t a
rgu
me
nts
C
OR
BA
::A
ny
val1
; va
l1 <
<=
(C
OR
BA
::S
ho
rt)
12
3;
CO
RB
A::
An
y va
l2;
val2
<<
= (
CO
RB
A::
Sh
ort
) 0
; C
OR
BA
::A
ny
val3
; va
l3 <
<=
(C
OR
BA
::S
ho
rt)
45
6;
// M
ake
re
qu
est
(sh
ort
form
) C
OR
BA
::R
eq
ue
st_p
tr r
q=
ob
j->
_re
qu
est
("o
p")
; //
Cre
ate
arg
um
en
t lis
t r
q->
arg
um
en
ts()
= o
rb->
cre
ate
_lis
t();
r
q->
arg
um
en
ts()
->a
dd
_va
lue
("a
rg1
",va
l1,C
OR
BA
::A
RG
_IN
);
rq
->a
rgu
me
nts
()->
ad
d_v
alu
e("
arg
2",
val2
,CO
RB
A::
AR
G_O
UT
);
rq
->a
rgu
me
nts
()->
ad
d_v
alu
e("
arg
3",
val3
,CO
RB
A::
AR
G_I
NO
UT
);
// S
tart
re
qu
est
(sy
nch
ron
ou
sly)
c
ou
t <
< "
sta
rt r
eq
ue
st"
<<
en
dl;
r
q->
invo
ke()
;
/
/ an
aly
ze r
esu
lt
CO
RB
A::
Sh
ort
rsl
t ;
if
(*(r
q->
resu
lt()
->va
lue
())
>>
= r
slt)
{
// A
na
lyze
th
e o
ut/
ino
ut-
pra
me
ters
(a
rg1
ha
s in
de
x 0
)
C
OR
BA
::S
ho
rt _
arg
2, _
arg
3;
*(rq
->a
rgu
me
nts
()->
ite
m(1
)->
valu
e()
) >
>=
_a
rg2
;
*(
rq->
arg
um
en
ts()
->it
em
(2)-
>va
lue
())
>>
= _
arg
3;
co
ut
<<
" a
rg2
= "
<
< _
arg
2 <
< "
arg
3=
" <
< _
arg
3
<
< "
re
turn
= "
<<
rsl
t <
< e
nd
l; }
e
lse
{
co
ut
<<
“re
sult
ha
s u
ne
xpe
cte
d t
ype
" <
< e
nd
l; }
}
Pro
f. U
. Aßm
ann,
CB
SE
29
DII
Invo
catio
n in
Jav
a (1
)
// Client.java
// Building Distributed Object Applications with CORBA
// Infowave (Thailand) Co., Ltd.
// http://www.waveman.com
// Jan 1998
public class Client {
public static void main(String[] args) {
if (args.length != 2) {
System.out.println("Usage: vbj Client <carrier-name> <aircraft-name>");
return;
}
String carrierName = args[0];
String aircraftName = args[1];
org.omg.CORBA.Object carrier = null;
org.omg.CORBA.Object aircraft = null;
org.omg.CORBA.ORB orb = null;
try {
orb = org.omg.CORBA.ORB.init(args, null);
}
catch (org.omg.CORBA.systemsxception se) {
System.err.println("ORB init failure " + se);
System.exit(1);
}
Pro
f. U
. Aßm
ann,
CB
SE
30
{ // scope
try {
carrier = orb.bind("IDL:Ship/AircraftCarrier:1.0",
carrierName, null, null);
} catch (org.omg.CORBA.systemsxception se) {
System.err.println("ORB init failure " + se);
System.exit(1);
}
org.omg.CORBA.Request request = carrier._request("launch");
request.add_in_arg().insert_string(aircraftName);
request.set_return_type(orb.get_priwithive_tc(
org.omg.CORBA.TCKind.tk_objref));
request.invoke();
aircraft = request.result().value().extract_Object();
}
{ // scope
org.omg.CORBA.Request request = aircraft._request("codeNumber");
request.set_return_type(orb.get_priwithive_tc(
org.omg.CORBA.TCKind.tk_string));
request.invoke();
String designation = request.result().value().extract_string();
System.out.println("Aircraft " + designation + " is coming your way");
}
DII
Invo
catio
n in
Jav
a (2
)
Pro
f. U
. Aßm
ann,
CB
SE
31
// Building Distributed Object Applications with CORBA
// Infowave (Thailand) Co., Ltd.
// http://www.waveman.com
// Jan 1998
public class Server {
public static void main(String[] args) {
org.omg.CORBA.ORB orb = null;
try {
orb = org.omg.CORBA.ORB.init(args, null);
} catch (org.omg.CORBA.systemsxception se) {
System.err.println("ORB init failure " + se);
System.exit(1);
}
org.omg.CORBA.BOA boa = null;
try {
boa = orb.BOA_init();
} catch (org.omg.CORBA.systemsxception se) {
System.err.println("BOA init failure " + se);
System.exit(1);
}
Ship.AircraftCarrier carrier =
new AircraftCarrierImpl("Nimitz");
try {
boa.obj_is_ready(carrier);
} catch (org.omg.CORBA.systemsxception se) {
System.err.println(
"Object Ready failure " + se);
System.exit(1);
}
System.out.println(
carrier + " ready for launch !!!");
try {
boa.impl_is_ready();
} catch (org.omg.CORBA.systemsxception se) {
System.err.println(
"Impl Ready failure " + se);
System.exit(1);
}
}
}
Serv
er Im
plem
enta
tion
Pro
f. U
. Aßm
ann,
CB
SE
32
Exam
ple:
Tim
e Se
rver
in J
ava
►
On
one
mac
hine
; 2 a
ddre
ss s
pace
s (p
roce
sses
) ►
Cal
l pro
vide
s cu
rren
t tim
e ►
Con
tain
s ■
IDL
■ S
erve
r .
Sta
rts O
RB
.
Initi
aliz
es S
ervi
ce
. G
ives
IOR
to th
e ou
tput
■ C
lient
.
Take
s IO
R
. C
alls
ser
vice
// TestTimeServer.idl
module TestTimeServer{
interface ObjTimeServer{
string getTime();
};
};
Pro
f. U
. Aßm
ann,
CB
SE
33
Serv
ice
Com
pone
nt
// TestTimeServerImpl.java – Server Skeleton
import CORBA.*;
class ObjTestTimeServerImpl extends
TestTimeServer.ObjTimeServer_Skeleton { // generated from IDL
// Variables
// Constructor
// Method (Service) Implementation
public String getTime() throws CORBA.SystemException {
return “Time: “ + currentTime;
}
};
Pro
f. U
. Aßm
ann,
CB
SE
34
Serv
er Im
plem
enta
tion
// TimeServer_Server.java
import CORBA.*;
public class TimeServer_Server{
public static void main(String[] argv){
try {
CORBA.ORB orb = CORBA.ORB.init();
…
ObjTestTimeServerImpl obj =
new ObjTestTimeServerImpl(…);
…
System.out.println(orb.object_to_string(obj));
}
catch (CORBA.SystemException e){
System.err.println(e);
}
}
};
Pro
f. U
. Aßm
ann,
CB
SE
35
Clie
nt Im
plem
enta
tion
(Sim
pler
Pro
toco
l)
// TimeServer_Client.java
import CORBA.*;
public class TimeServer_Client{
public static void main(String[] argv){
try {
CORBA.ORB orb= CORBA.ORB.init();
…
CORBA.object obj = orb.string_to_object(argv[0]);
…
TestTimeServer.ObjTimeServer timeServer =
TestTimeServerImpl.ObjTimeServer_var.narrow(obj);
…
System.out.println(timeServer.getTime());
}
catch (CORBA.SystemException e){
System.err.println(e);
}
}
};
Pro
f. U
. Aßm
ann,
CB
SE
36
Exec
utio
n
// starting server
C:\> java TimeServer_Server
IOR:00000000000122342435 …
// starting client
C:\> java TimeServer_Client IOR:00000000000122342435 …
Time: 14:35:44
Pro
f. U
. Aßm
ann,
CB
SE
37
OR
Bs
►
Java
-bas
ed
■ IB
M W
ebS
pher
e ■
ION
A O
rbix
: In
Java
, O
RB
lets
pos
sibl
e ■
BE
A W
ebLo
gic
■ V
isib
roke
r (in
Net
scap
e)
■ V
oyag
er (O
bjec
tSpa
ce) (
with
M
obile
Age
nts)
■
free:
Jac
OR
B, I
LU, J
orba
, D
ynaO
RB
►
C-b
ased
■
AC
E O
RB
TA
O, U
nive
rsity
W
ashi
ngto
n (w
ith tr
ader
)
■ Li
nux
OR
BIT
(gno
me)
■ Li
nux
MIC
O
►
Pyth
on-b
ased
■
fnor
b
►
http
://w
ww
.om
g.or
g
CB
SE
, © P
rof.
Uw
e A
ßman
n 38
11b.
2.2
Trad
er-B
ased
Cal
l
The
foun
datio
n of
ser
vice
-orie
nted
arc
hite
ctur
e (S
OA
)
Pro
f. U
. Aßm
ann,
CB
SE
39
Bey
ond
Dyn
amic
Cal
l: Se
rvic
e C
all w
ith th
e Tr
ader
Ser
vice
►
A s
ervi
ce c
all i
s a
call,
not
bas
ed o
n na
min
g bu
t on
sem
antic
at
tribu
tes,
pub
lishe
d pr
oper
ties
■
Req
uire
s a
yello
w p
age
dire
ctor
y of
ser
vice
s
►
Ser
vice
-orie
nted
arc
hite
ctur
es (S
OA
), re
quire
s m
atch
mak
ing
of
serv
ices
■
The
OR
B re
solv
es o
pera
tions
stil
l bas
ed o
n na
min
g (w
ith th
e na
me
serv
ice)
. The
tra
der,
how
ever
, res
olve
s se
rvic
es w
ithou
t nam
es, o
nly
base
d on
pro
perti
es a
nd
polic
ies
►
The
trade
r get
s of
fers
from
ser
vers
, con
tain
ing
new
ser
vice
s
Trad
er
Clie
nt S
ervi
ce
Med
iato
r pat
tern
, m
edia
tor l
ets
clie
nts
look
up s
ervi
ces
Inte
ract
Impo
rt fu
nctio
nalit
y E
xpor
t fu
nctio
nalit
y
Pro
f. U
. Aßm
ann,
CB
SE
40
Serv
ice
Offe
rs fo
r Tra
der
►
Ser
vice
offe
r (IO
R w
ith p
rope
rties
(met
adat
a))
■ P
rope
rties
des
crib
e se
rvic
es
■ A
re u
sed
by tr
ader
s to
mat
ch s
ervi
ces
to q
uerie
s ■
not f
acet
-bas
ed, o
ne-d
imen
sion
al
►
Dyn
amic
pro
perty
■
A p
rope
rty c
an b
e qu
erie
d dy
nam
ical
ly b
y th
e tra
der o
f ser
vice
■
The
serv
ice-
obje
ct c
an d
eter
min
e th
e va
lue
of a
dyn
amic
pro
perty
ane
w
►
Mat
chin
g w
ith th
e st
anda
rd c
onst
rain
t lan
guag
e ■
Boo
lean
exp
ress
ions
abo
ut p
rope
rties
■
Num
eric
and
stri
ng c
ompa
rison
s
Pro
f. U
. Aßm
ann,
CB
SE
41
Trad
ers
Prov
ide
Serv
ice
Hop
ping
►
If a
trade
r doe
sn’t
find
a se
rvic
e, it
ca
lls n
eigh
bor t
rade
rs
■ D
esig
n pa
ttern
Cha
in o
f R
espo
nsib
ility
►
Gra
ph o
f tra
ders
■
Link
s to
nei
ghbo
rs v
ia
Trad
erLi
nk
■ Tr
ader
Link
filte
rs
quer
ies
and
m
anip
ulat
e vi
a po
licie
s
trade
r 1
trade
r 1
trade
r 4
trade
r 3
trade
r 2
Pol
icie
s, th
at
chan
ge th
e va
lues
of
the
prop
ertie
s du
ring
pass
ing
on
Flow
of t
he
prop
ertie
s of
th
e se
rvic
e qu
ery
Offe
rs w
ith
the
trade
r
Pro
f. U
. Aßm
ann,
CB
SE
42
Mod
ifica
tion
of Q
uerie
s
►
Pol
icie
s pa
ram
eter
ize
the
beha
viou
r of t
he tr
ader
s an
d th
e Tr
ader
Link
s
■ Fi
lters
, i.e
., va
lues
, mod
ifyin
g th
e qu
erie
s:
■ m
ax_s
earc
h_ca
rd: m
axim
um c
ardi
nalit
y fo
r the
ong
oing
sea
rche
s
■ m
ax_m
atch
_car
d: m
axim
um c
ardi
nalit
y fo
r mat
chin
gs
■ m
ax_h
op_c
ount
: car
dina
lity
sear
ch d
epth
in th
e gr
aph
po
ssib
le
off
ers
po
ssib
le
off
ers
po
ssib
le
off
ers
po
ssib
le
off
ers
fou
nd
off
ers
inve
stig
ated
o
ffer
s
ca
rdin
alit
ies
for
sea
rch
c
ard
ina
litie
s
for
mat
chin
g
Ca
rdin
alit
ies
fo
r re
turn
off
ers
Pro
f. U
. Aßm
ann,
CB
SE
43
Inte
rfac
es T
radi
ng S
ervi
ce
►
Bas
ic in
terfa
ces
■ Lo
okup
(que
ry)
■ R
egis
ter (
for e
xpor
t, re
tract
, im
port
of s
ervi
ces)
■ A
dmin
(inf
o ab
out s
ervi
ces)
■ Li
nk (c
onst
ruct
ion
of t
rade
r gra
ph)
►
How
doe
s a
look
up q
uery
look
like
? ■
Lookup.Query(in ServicetypeName, in Constraint,
in PolicySeq, in SpecifiedProperties,
in howTo, out OfferSequence, offerIterator)
►
Unf
ortu
nate
ly, n
o fa
cete
d m
atch
mak
ing
poss
ible
!
Pro
f. U
. Aßm
ann,
CB
SE
44
CO
RB
A T
rade
r Typ
es
Lo
oku
p
sim
ple
trade
r
Lo
oku
p
stan
dalo
ne
trade
r
Lo
oku
p R
eg
iste
r R
eg
iste
r A
dm
in
soc
ial t
rad
er
(lin
ked
tra
de
r)
Lo
oku
p Re
gis
ter
Ad
min
Lin
k
sub
stit
ute
t
rad
er
(pro
xy t
rad
er)
Lo
oku
p Re
gis
ter
Ad
min
pro
xy
full-
serv
ice
tra
de
r
Lo
oku
p Re
gis
ter
Ad
min
Lin
k p
roxy
quer
y tra
der
Pro
f. U
. Aßm
ann,
CB
SE
45
Cor
ba 3
.0
►
Pro
vide
s th
e w
ell-d
efin
ed p
acka
ging
for p
rodu
cing
com
pone
nts
■ C
OR
BA
Com
pone
nt M
odel
(CC
M):
sim
ilar t
o E
JB
►
Mes
sage
Ser
vice
MO
M: O
bjec
ts h
ave
asyn
chro
nous
buf
fere
d m
essa
ge q
ueue
s
►
Lang
uage
map
ping
s av
oid
IDL
►
Gen
erat
ing
IDL
from
lang
uage
spe
cific
type
def
initi
ons
►
C++
2ID
L, J
ava2
IDL,
…
►
XM
L in
tegr
atio
n (S
OA
P m
essa
ges)
►
Scr
iptin
g (C
OR
BA
scr
ipt),
a c
ompo
sitio
n la
ngua
ge
CB
SE
, © P
rof.
Uw
e A
ßman
n 46
11b.
3 Ev
alua
tion
of C
OR
BA
as c
ompo
sitio
n sy
stem
Pro
f. U
. Aßm
ann,
CB
SE
47
Com
pone
nt M
odel
►
Mec
hani
sms
for s
ecre
ts a
nd tr
ansp
aren
cy: v
ery
good
■
Inte
rface
and
Impl
emen
tatio
n re
posi
tory
■
Com
pone
nt la
ngua
ge h
idde
n (in
tero
pera
bilit
y)
■ Li
fe-ti
me
of s
ervi
ce h
idde
n ■
Iden
tity
of s
ervi
ces
hidd
en
■ Lo
catio
n hi
dden
►
No
para
met
eriz
atio
n ►
Sta
ndar
diza
tion:
qui
te g
ood!
■
Ser
vice
s, a
pplic
atio
n se
rvic
es a
re a
vaila
ble
■ O
n th
e ot
her h
and,
som
e st
anda
rds
are
FAT
■ Te
chni
cal v
s. a
pplic
atio
n sp
ecifi
c vs
bus
ines
s co
mpo
nent
s:
■ ..
but f
or b
usin
ess
obje
cts,
the
stan
dard
s m
ust b
e ex
tend
ed (v
ertic
al fa
cilit
ies)
(th
ats´
s w
here
the
mon
ey is
)
Pro
f. U
. Aßm
ann,
CB
SE
48
Com
posi
tion
Tech
niqu
e
►
Mec
hani
sms
for c
onne
ctio
n ■
Mec
hani
sms
for a
dapt
atio
n .
Stu
bs, s
kele
tons
, ser
ver a
dapt
ers
■ M
echa
nism
s fo
r glu
eing
: mar
shal
ling
base
d on
IDL
►
Mec
hani
sms
for a
spec
t sep
arat
ion
■ M
ultip
le in
terfa
ces
per o
bjec
t .
Faca
de c
lass
es/o
bjec
ts (d
esig
n pa
ttern
faca
de)
►
Not
hing
for e
xten
sion
s ►
Mec
hani
sms
for m
eta-
mod
elin
g ■
Inte
rface
Rep
osito
ries
with
type
cod
es
■ Im
plem
enta
tion
repo
sito
ries
■ D
ynam
ic c
all a
nd tr
aded
cal
l are
refle
ctiv
e an
d in
trosp
ectiv
e
►
Sca
labi
lity
■ C
onne
ctio
ns c
anno
t eas
ily b
e ex
chan
ged
(exc
ept s
tatic
loca
l and
rem
ote
call)
Pro
f. U
. Aßm
ann,
CB
SE
49
Com
posi
tion
Lang
uage
►
Wea
k: C
OR
BA
scr
iptin
g pr
ovid
es th
e a
faci
lity
to w
rite
glue
cod
e, b
ut
only
bla
ck-b
ox c
ompo
sitio
n
Pro
f. U
. Aßm
ann,
CB
SE
50
CO
RB
A
Sca
labi
lity
Ada
ptat
ion
Met
acom
posi
tion
Asp
ect S
epar
atio
n
Ext
ensi
bilit
y S
oftw
are
proc
ess
Con
nect
ion
Pro
duct
qua
lity
CB
SE
, © P
rof.
Uw
e A
ßman
n 51
11b.
4 C
orba
Ser
vice
s
(opt
iona
l mat
eria
l)
Pro
f. U
. Aßm
ann,
CB
SE
52
Lite
ratu
re
►
OM
G. C
OR
BA
ser
vice
s: C
omm
on O
bjec
t Ser
vice
Spe
cific
atio
ns.
http
://w
ww
.om
g.or
g.
►
OM
G: C
OR
BA
faci
litie
s: C
omm
on O
bjec
t Fac
ilitie
s S
peci
ficat
ions
.
Pro
f. U
. Aßm
ann,
CB
SE
53
Ove
rvie
w o
n C
orba
Ser
vice
s
►
Ser
vice
s pr
ovid
e fu
nctio
nalit
y a
prog
ram
min
g la
ngua
ge m
ight
not
pr
ovid
e (e
.g, C
obol
, For
tran)
►
16+
stan
dard
ized
ser
vice
inte
rface
s (i.
e., a
libr
ary)
■
Sta
ndar
dize
d, b
ut s
tatu
s of
impl
emen
tatio
n di
ffere
nt d
epen
ding
on
prod
ucer
►
Obj
ect s
ervi
ces
■ D
eal w
ith fe
atur
es a
nd m
anag
emen
t of o
bjec
ts
►
Col
labo
ratio
n se
rvic
es
■ D
eal w
ith c
olla
bora
tion,
i.e.
, obj
ect c
onte
xts
►
Bus
ines
s se
rvic
es
■ D
eal w
ith b
usin
ess
appl
icat
ions
►
The
serv
ices
ser
ve fo
r crit
erio
n M
-3, s
tand
ardi
zatio
n. T
hey
are
very
im
porta
nt to
incr
ease
reus
e.
■ R
emem
ber,
they
are
ava
ilabl
e fo
r eve
ry la
ngua
ge, a
nd o
n di
strib
uted
sys
tem
s!
Pro
f. U
. Aßm
ann,
CB
SE
54
Obj
ect S
ervi
ces:
Rat
her S
impl
e
►
Nam
e se
rvic
e (d
irect
ory
serv
ice)
■
Rec
ords
ser
ver o
bjec
ts in
a s
impl
e tre
e-lik
e na
me
spac
e ■
(Is a
sim
ple
com
pone
nt s
yste
m it
self)
►
Life
cycl
e se
rvic
e (a
lloca
tion
serv
ice)
■
Not
aut
omat
ic; s
eman
tics
of d
eallo
catio
n un
defin
ed
►
Pro
perty
ser
vice
(fea
ture
ser
vice
for o
bjec
ts)
►
Per
sist
ency
ser
vice
(sto
ring
obje
cts
in d
ata
base
s)
►
Rel
atio
nshi
p se
rvic
e to
bui
ld in
tero
pera
ble
rela
tions
and
gra
phs
■ S
uppo
rt of
sta
ndar
d re
latio
ns re
fere
nce,
con
tain
men
t ■
Div
ided
in s
tand
ard
role
s co
ntai
ns, c
onta
ined
In, r
efer
ence
s, re
fere
nced
►
Con
tain
er s
ervi
ce (c
olle
ctio
n se
rvic
e)
Pro
f. U
. Aßm
ann,
CB
SE
55
Col
labo
ratio
n Se
rvic
es
►
Com
mun
icat
ion
serv
ices
■
Res
embl
e co
nnec
tors
in a
rchi
tect
ure
syst
ems,
but
can
not b
e ex
chan
ged
to e
ach
othe
r
■ E
vent
ser
vice
. pu
sh m
odel
: the
com
pone
nts
push
eve
nts
into
the
even
t cha
nnel
. pu
ll m
odel
: the
com
pone
nts
wai
t at t
he c
hann
el a
nd e
mpt
y it
■ C
allb
ack
serv
ice
►
Par
alle
lism
■
Con
curr
eny
serv
ice:
lock
s
■ O
bjec
t tra
nsac
tion
serv
ice,
OTS
: Fla
t tra
nsac
tions
on
obje
ct g
raph
s
. N
este
d tra
nsac
tions
?
Pro
f. U
. Aßm
ann,
CB
SE
56
Bus
ines
s Se
rvic
es
►
Trad
er s
ervi
ce
■ Y
ello
w P
ages
, loc
aliz
atio
n of
ser
vice
s
►
Que
ry s
ervi
ce
■ S
earc
h fo
r obj
ects
with
attr
ibut
es a
nd th
e O
QL,
SQ
L (O
DM
G-9
3)
►
Lice
nsin
g se
rvic
e ■
For a
pplic
atio
n pr
ovid
ers
(app
licat
ion
serv
ers)
■ Li
cens
e m
anag
ers
►
Sec
urity
ser
vice
■
Use
of S
SL
and
othe
r bas
ic s
ervi
ces
Pro
f. U
. Aßm
ann,
CB
SE
57
Dep
ende
ncie
s B
etw
een
the
Serv
ices
Nam
es
Life
-tim
e
Rel
atio
ns
Per
sist
ency
M
arsh
allin
g
Con
curr
ency
Tran
sact
ions
Que
ry
Trad
er
Pro
perti
es
Sec
urity
Eve
nts
Lice
nses
Col
lect
ions
C
allb
ack
Pro
f. U
. Aßm
ann,
CB
SE
58
Obj
ect S
ervi
ces:
Nam
es
►
Bin
ding
of
a na
me
asso
ciat
es a
nam
e to
an
obje
ct in
a n
ame
spac
e (d
irect
ory,
sco
pe, n
amin
g co
ntex
t) ■
A n
ame
spac
e is
an
asso
ciat
ive
arra
y w
ith a
set
of b
indi
ngs
of n
ames
to v
alue
s ■
Nam
espa
ces
are
recu
rsiv
e, i.
e., t
hey
can
refe
renc
e ea
ch o
ther
and
bui
ld n
ame
grap
hs
■ O
ther
s: A
ctiv
e D
irect
ory,
LD
AP
►
The
repr
esen
tatio
n of
a n
ame
is b
ased
on
abst
ract
syn
tax,
not
on
the
conc
rete
syn
tax
of a
ope
ratin
g sy
stem
or U
RL.
■
A n
ame
cons
ists
of a
tupl
e (Id
entif
ier,
Kin
d).
■ Th
e id
entif
ier i
s th
e re
al n
ame,
the
Kin
d te
lls h
ow th
e na
me
is re
pres
ente
d (e
.g.,
c_so
urce
, obj
ect_
code
, exe
cuta
ble,
pos
tscr
ipt,.
.).
■ Fo
r cre
atio
n of
nam
es th
ere
is a
libr
ary
(des
ign
patte
rn A
bstra
ct F
acto
ry).
Pro
f. U
. Aßm
ann,
CB
SE
59
Nam
e Se
rvic
e C
osN
amin
g
bind
(in N
ame
n, in
Obj
ect o
bj) /
/ ass
ocia
te a
nam
e re
bind
(in N
ame
n, in
Obj
ect o
bj)
bind
_con
text
re
bind
_con
text
m
k_na
me(
Stri
ng s
) O
bjec
t res
olve
un
bind
(in N
ame
n) /
/ dis
asso
ciat
e a
nam
e N
amin
gCon
text
new
_con
text
; N
amin
gCon
text
bin
d_ne
w_c
onte
xt(in
Nam
e n)
vo
id d
estro
y vo
id li
st(..
)
_nar
row
()
Cos
Nam
ing:
:Nam
ingC
onte
xt
Pro
f. U
. Aßm
ann,
CB
SE
60
Nam
e Se
rvic
e
void bind(in Name n, in Object obj)
raises(NotFound, Cannotproceed, InvalidName, AlreadyBoand);
void rebind(in Name n, in Object obj)
raises(NotFound, Cannotproceed, InvalidName );
void bind_context(in Name n, in NamingContext nc)
raises(NotFound, Cannotproceed, InvalidName, AlreadyBoand );
void rebind_context(in Name n, in NamingContext nc)
raises( NotFound, Cannotproceed, InvalidName );
Name mk_name(String s);
Object resolve(in Name n)
raises( NotFound, Cannotproceed, InvalidName );
void unbind(in Name n)
raises( NotFound, Cannotproceed, InvalidName );
NamingContext new_context();
NamingContext bind_new_context(in Name n)
raises( NotFound, AlreadyBoand, Cannotproceed, InvalidName );
void destroy()
raises( NotEmpty );
void list(in unsigned long how_many,
out BindingLis bl, out Bindingeserator bi );
Pro
f. U
. Aßm
ann,
CB
SE
61
Nam
e Se
rvic
e in
IDL
module CosNaming{
struct NameComponent {
string id;
string kind;
};
typedef sequence <NameComponent> Name;
enum BindingType { nobject, ncontext };
struct Binding {
Name binding_name;
BindingType binding_type;
};
typedef sequence <Binding> BindingList;
interface BindingIterator;
interface NamingContext {
enum NotFoundReason { missing_node,
not_context, not_object };
exception NotFound {
NotFoundReason why;
Name rest_of_name;
};
}
exception Cannotproceed {
NamingContext cxt;
Name rest_of_name;
};
exception InvalidName {};
exception AlreadyBoand {};
exception NotEmpty {};
// methods see previous slide
};
interface BindingIterator {
boolean next_one(out Binding b);
boolean next_n(in unsigned long
how_many,
out BindingLis bl);
void destroy();
};
…
Pro
f. U
. Aßm
ann,
CB
SE
62
Bin
din
g (a
sso
cia
tio
n)
Se
arc
h/c
reat
e n
am
e s
pa
ce
Use
of N
ames
Sys
tem
de
pe
nd
en
t n
am
e Co
rba
-Na
me
ob
jec
t
Se
arc
h O
bje
ct
na
me
sp
ac
e
Cre
ate
Na
me
ob
jec
t
Pro
f. U
. Aßm
ann,
CB
SE
63
Nam
e Se
rvic
e: E
xam
ple
// From: Redlich
import java.io.*;
import java.awt.*;
import IE.Iona.Orbix2.CORBA.SystemException; // OrbixWeb
import CosNaming.NamingContext; // name service/context
import CosNaming.NamingContext.*; // name service/Exceptions
import Calc5.calc.complex; // Typ 'complex' from Calc5
class MyNaming extends CosNaming {
...
}
public class client extends Frame {
private Calc5.calc.Ref calc;
private TextField inR, inI;
private Button setB, addB, multB,
divB, quitB, zeroB;
public static void main(String argv[])
{
CosNaming.NamingContext.Ref cxt;
Calc5.calc_factory.Ref cf;
Frame f;
try {
cxt= NamingContext._narrow( MyNaming.
resolve_initial_references(MyNaming.NameService));
cf = Calc5.calc_factory._narrow(
cxt.resolve(MyNaming.mk_name("calcfac")));
f = new client(cf.create_new_calc());
f.pack();
f.show();
}
catch (Exception ex) {
System.out.println("Calc-5/Init:" + ex.toString());
}
}
Pro
f. U
. Aßm
ann,
CB
SE
64
Obj
ect S
ervi
ces:
Per
sist
ency
►
Def
initi
on o
f a P
ersi
sten
t Obj
ect I
dent
ifier
(PID
) ■
refe
renc
es th
e va
lue
of C
OR
BA
-obj
ects
(in
cont
rast
to a
CO
RB
A-o
bjec
t)
►
Inte
rface
■
conn
ect,
disc
onne
ct, s
tore
, res
tore
, del
ete
►
Atta
chm
ent t
o da
ta b
ases
pos
sibl
e (a
lso
OD
MG
com
patib
le)
Pro
f. U
. Aßm
ann,
CB
SE
65
Obj
ect S
ervi
ces:
Pro
pert
y Se
rvic
e
►
Man
agem
ent o
f lis
ts o
f fea
ture
s (p
rope
rties
) for
obj
ects
■
Pro
perti
es a
re s
tring
s
■ D
ynam
ical
ly e
xten
sibl
e
►
Con
cept
wel
l-kno
wn
as
■ LI
SP
pro
perty
list
s, a
ssoc
iativ
e ar
rays
, Jav
a pr
oper
ty c
lass
es
►
Itera
tors
for p
rope
rties
►
Inte
rface
: ■
defin
e_pr
oper
ty, d
efin
e_pr
oper
ties,
get
_pro
perty
_val
ue, g
et_p
rope
rties
, de
lete
_pro
perty
,
Pro
f. U
. Aßm
ann,
CB
SE
66
Col
labo
ratio
n Se
rvic
es: T
rans
actio
ns
►
Wha
t a d
ream
: the
Web
as
data
bas
e w
ith n
este
d tra
nsac
tions
. S
cena
rios:
■
Acc
ount
s as
Web
-obj
ects
. Tra
nsfe
rs a
s Tr
ansa
ctio
n on
the
obje
cts
of s
ever
al
bank
s
■ P
aral
lel w
orki
ng o
n w
eb s
ites:
how
to m
ake
cons
iste
nt?
►
Sta
ndar
d 2-
phas
e co
mm
it pr
otoc
ol:
■ be
gin_
ta, r
ollb
ack,
com
mit
►
Nes
ted
trans
actio
ns
■ be
gin_
subt
rans
actio
n, ro
llbac
k_su
btra
nsac
tion,
com
mit_
subt
rans
actio
n
CB
SE
, © P
rof.
Uw
e A
ßman
n 67
11b.
5 C
OR
BA
Fac
ilitie
s
(Sta
ndar
ds fo
r App
licat
ion
Dom
ains
)
App
licat
ion
dom
ain
spec
ific
inte
rface
s
Pro
f. U
. Aßm
ann,
CB
SE
68
Hor
izon
tal F
acili
ties
►
Use
r int
erfa
ces
■ P
rintin
g, S
crip
ting
■ C
ompo
und
docu
men
ts: s
ince
199
6 O
penD
oc is
acc
epte
d as
sta
ndar
d fo
rmat
. S
ourc
e C
ode
has
been
rele
ased
of I
BM
►
Info
rmat
ion
man
agem
ent
■ M
etad
ata(
met
a ob
ject
faci
lity,
MO
F)
■ To
ol in
terc
hang
e: a
text
- and
stre
am b
ased
exc
hang
efor
mat
for U
ML
(XM
I)
■ C
omm
on W
areh
ouse
Mod
el (C
WM
): M
OF-
base
d m
etas
chem
a fo
r dat
abas
e ap
plic
atio
ns
Pro
f. U
. Aßm
ann,
CB
SE
69
Vert
ical
Fac
ilitie
s (D
omai
n-Sp
ecifi
c Fa
cilit
ies)
Th
e D
omai
n te
chno
logy
com
mitt
ee (D
TC) c
reat
es d
omai
n ta
sk fo
rces
DTF
for a
ap
plic
atio
n do
mai
n
►
Bus
ines
s ob
ject
s ►
Fina
nce/
insu
ranc
e ■
Cur
renc
y fa
cilit
y
►
Ele
ctro
nic
com
mer
ce
►
Man
ufac
turin
g ■
Pro
duct
dat
a m
anag
emen
t ena
bler
s P
DM
►
Med
icin
e (h
ealth
care
Cor
baM
ed)
■ Le
xico
n Q
uery
Ser
vice
■ P
erso
n Id
entif
ier S
ervi
ce P
IDS
►
Tele
com
mun
icat
ions
■
Aud
io/v
isua
l stre
am c
ontro
l obj
ect
■ N
otifi
catio
n se
rvic
e
►
Tran
spor
tatio
n
Pro
f. U
. Aßm
ann,
CB
SE
70
CO
RB
A F
acili
ties
and
UM
L Pr
ofile
s
►
Sin
ce 2
000,
the
OM
G d
escr
ibes
dom
ain-
spec
ific
voca
bula
ries
with
U
ML
prof
iles
■ P
roba
bly,
all
CO
RB
A fa
cilit
ies
will
end
up
in U
ML
prof
iles
►
A U
ML
Pro
file
is a
UM
L di
alec
t of a
app
licat
ion
spec
ific
dom
ain
■ W
ith n
ew s
tere
otyp
es a
nd ta
gged
val
ues
■ C
orre
spon
ds to
an
exte
nsio
n of
the
UM
L m
etam
odel
■
Cor
resp
onds
to a
dom
ain
spec
ific
lang
uage
with
ow
n vo
cabu
lary
■
Eve
ry e
ntry
in p
rofil
e is
a te
rm
►
Exa
mpl
e U
ML
Pro
files
: ■
ED
OC
Ent
erpr
ise
Dis
tribu
ted
Obj
ects
Com
putin
g ■
Mid
dlew
are
prof
iles:
Cor
ba, .
NE
T, E
JB
■ E
mbe
dded
and
real
tim
e sy
stem
s:
. M
AR
TE p
rofil
e on
sch
edul
abili
ty, p
erfo
rman
ce, t
ime
. R
aven
scar
Pro
file
.
HID
OO
RS
Pro
file
on re
al-ti
me
mod
ellin
g w
ww
.hid
oors
.org
CB
SE
, © P
rof.
Uw
e A
ßman
n 71
11b.
6. C
OR
BA
and
the
Web
Pro
f. U
. Aßm
ann,
CB
SE
72
Cor
ba a
nd th
e W
eb
►
HTM
L so
lves
man
y of
the
CO
RB
A p
robl
ems
►
HTT
P o
nly
for d
ata
trans
port
■ H
TTP
can
not c
all m
etho
ds, e
xcep
t by
CG
I-Gat
eway
-func
tiona
lity
(com
mon
ga
tew
ay in
terfa
ce)
■ B
ehin
d th
e C
GI-i
nter
face
is a
gen
eral
s pr
ogra
m, c
omm
unic
atin
g w
ith H
TTP
with
un
type
d en
viro
nmen
t var
iabl
es (
HA
CK
!)
■ ht
tp-S
erve
r are
sim
ple
OR
Bs,
pag
es a
re o
bjec
ts
■ Th
e U
RI/U
RL-
nam
e sc
hem
a ca
n be
inte
grat
ed in
to C
OR
BA
►
IIOP
bec
omes
a s
tand
ard
inte
rnet
pro
toco
l ■
Sta
ndar
d po
rts, U
RL-
map
ping
s an
d S
tand
ard-
prox
ies
for F
irew
alls
are
ava
ilabl
e
►
CO
RB
A is
an
exte
nsio
n of
HTT
P o
f dat
a to
cod
e
Pro
f. U
. Aßm
ann,
CB
SE
73
CO
RB
A a
nd J
ava
►
Java
is a
n id
eal p
artn
er fo
r Cor
ba :
■ B
ytec
ode
is m
obile
, i.e
.,
. A
pple
ts:
mov
e ca
lcul
atio
ns to
clie
nts
(thin
/thic
k cl
ient
pro
blem
) .
can
be u
sed
for m
igra
tion
of o
bjec
ts, O
RB
s an
d ag
ents
■
Sin
ce 1
999
dire
ct C
orba
sup
port
in J
DK
1.2
.
IDL2
Java
map
ping
, ID
L co
mpi
ler,
Java
2ID
L co
mpi
ler,
nam
e se
rvic
e, O
RB
■
Cor
ba s
uppo
rts fo
r Jav
a a
dist
ribut
ed in
tero
pera
ble
infra
stru
ctur
e
►
Java
imita
tes
func
tiona
lity
of C
orba
■
Bas
ic s
ervi
ces:
Rem
ote
Met
hod
Invo
catio
n R
MI,
Java
Nat
ive
code
Inte
rface
JN
I ■
Ser
vice
s: s
eria
lizat
ion,
eve
nts
■ A
pplic
atio
n sp
ecifi
c se
rvic
es (f
acili
ties)
: ref
lect
ion,
pro
perti
es o
f Jav
aBea
ns
Pro
f. U
. Aßm
ann,
CB
SE
74
Cor
ba a
nd th
e W
eb (O
rble
ts)
►
OR
Bs
can
be w
ritte
n as
byt
ecod
e ap
plet
s if
they
are
writ
ten
in J
ava
(OR
Ble
t) ►
Cou
plin
g of
HTT
P a
nd II
OP
: Dow
nloa
d of
an
OR
Ble
ts w
ith H
TTP
: Ta
lk to
thi
s O
RB
, to
get c
onta
ct to
ser
ver
►
Sta
ndar
d w
eb s
ervi
ces
(see
late
r) a
re s
low
er th
an C
OR
BA
/OR
Ble
ts,
beca
use
they
incu
r int
erpr
etat
ion
over
head
OR
B
Htt
p s
erv
er
OR
B S
erv
er
We
b-C
lien
t W
eb
se
rve
r 1
) Fe
tch
pa
ge
2)
fetc
h O
RB
let
Bu
sin
ess
ob
jec
ts
3)
co
mm
un
icat
e w
ith
IIO
P
dat
a b
ase
s
Lo
tus
No
tes
Pro
f. U
. Aßm
ann,
CB
SE
75
Wha
t Hav
e W
e Le
arne
d
►
CO
RB
A is
big
, but
uni
vers
al:
■ Th
e C
orba
-inte
rface
s ar
e ve
ry fl
exib
le, w
ork
and
can
be u
sed
in p
ract
ice
■ ..
but a
lso
com
plex
and
fat,
may
be
too
flexi
ble
■ If
you
have
to c
onne
ct to
lega
cy s
yste
ms,
CO
RB
A w
orks
►
Cor
ba h
as th
e ad
vant
age
of a
n op
en s
tand
ard
►
To in
crea
se re
use
and
inte
rope
rabi
lity
in p
ract
ice,
one
has
to le
arn
man
y st
anda
rds
►
Trad
ing
and
dyna
mic
cal
l are
futu
re a
dvan
ced
com
mun
icat
ion
mec
hani
sms
►
CO
RB
A w
as p
roba
bly
only
the
first
ste
p, b
ut w
eb s
ervi
ces
mig
ht b
e ta
king
ove
r
Pro
f. U
. Aßm
ann,
CB
SE
76
The
End
