figure 12 - cs.boisestate.educs.boisestate.edu/~jhyeh/cs410/cs410_bookfigures_ch12.pdf · ©...

© Addison Wesley Longman, Inc. 2000, Elmasri/Navathe, Fundamentals of Database Systems, Third Edition

Figure 12.1a Overview of the interface definitions for part of the ODMG

object model. The basic Object interface, inherited by all objects.

interface Object {...boolean same_as(in Object other_object);Object copy();void delete();

};


inte

rfac

e D

ate

: Obj

ect {

enum

Wee

kday

{Sun

day,

Mon

day,

Tue

sday

, Wed

nesd

ay, T

hurs

day,

Frid

ay, S

atur

day}

;en

umM

onth

{Jan

uary

, Feb

ruar

y, M

arch

, Apr

il, M

ay, J

une,

Jul

y, A

ugus

t, S

epte

mbe

r, O

ctob

er, N

ovem

ber,

Dec

embe

r};

unsi

gned

sho

rtye

ar()

;un

sign

ed s

hort

mon

th()

;un

sign

ed s

hort

day(

);… bo

olea

nis

_equ

al(in

Dat

e ot

her_

Dat

e);

bool

ean

is_g

reat

er(in

Dat

e ot

her_

Dat

e);

…}; in

terf

ace

Tim

e : O

bjec

t {… un

sign

ed s

hort

hour

();

unsi

gned

sho

rtm

inut

e();

unsi

gned

sho

rtse

cond

();

unsi

gned

sho

rtm

illis

econ

d();

… bool

ean

is_e

qual

(in T

ime

othe

r_T

ime)

;bo

olea

nis

_gre

ater

(in T

ime

othe

r_T

ime)

;… T

ime

add_

inte

rval

(in In

terv

al s

ome_

Inte

rval

);T

ime

subt

ract

_int

erva

l(in

Inte

rval

som

e_In

terv

al);

Inte

rval

subt

ract

_tim

e(in

Tim

e ot

her_

Tim

e);

}; inte

rfac

e T

imes

tam

p : O

bjec

t {… un

sign

ed s

hort

year

();

unsi

gned

sho

rtm

onth

();

unsi

gned

sho

rtda

y();

unsi

gned

sho

rtho

ur()

;un

sign

ed s

hort

min

ute(

);un

sign

ed s

hort

seco

nd()

;un

sign

ed s

hort

mill

isec

ond(

);… T

imes

tam

ppl

us(in

Inte

rval

som

e_In

terv

al);

Tim

esta

mp

min

us(in

Inte

rval

som

e_In

terv

al);

bool

ean

is_e

qual

(in T

imes

tam

p ot

her_

Tim

esta

mp)

;bo

olea

nis

_gre

ater

(in T

imes

tam

p ot

her_

Tim

esta

mp)

;…

}; inte

rfac

e In

terv

al :

Obj

ect {

unsi

gned

sho

rtda

y();

unsi

gned

sho

rtho

ur()

;un

sign

ed s

hort

min

ute(

);un

sign

ed s

hort

seco

nd()

;un

sign

ed s

hort

mill

isec

ond(

);… In

terv

alpl

us(in

Inte

rval

som

e_In

terv

al);

Inte

rval

min

us(in

Inte

rval

som

e_In

terv

al);

Inte

rval

prod

uct(

in lo

ng s

ome_

valu

e);

Inte

rval

quot

ient

(in lo

ng s

ome_

valu

e);

bool

ean

is_e

qual

(in In

terv

al o

ther

_Int

erva

l);bo

olea

nis

_gre

ater

(in In

terv

al o

ther

_Int

erva

l);…

};

Figure 12.1b Overview of the interface definitions for part of the ODMG

object model. Some standard interfaces for structured literals.


inte

rfac

e C

olle

ctio

n : O

bjec

t {... ex

cept

ion

Ele

men

tNot

Fou

nd{a

ny e

lem

ent;

};un

sign

ed lo

ngca

rdin

ality

();

bool

ean

is_e

mpt

y();

... bool

ean

cont

ains

_ele

men

t(in

any

ele

men

t);

void

inse

rt_e

lem

ent(

in a

ny e

lem

ent)

;vo

idre

mov

e_el

emen

t(in

any

ele

men

t)

rai

ses(

Ele

men

tNot

Fou

nd);

Itera

tor

crea

te_i

tera

tor(

in b

oole

an s

tabl

e);

...}; in

terf

ace

Itera

tor

{ex

cept

ion

NoM

oreE

lem

ents

();

... bool

ean

is_s

tabl

e();

bool

ean

at_e

nd()

;vo

idre

set(

);an

yge

t_el

emen

t()

rais

es(N

oMor

eEle

men

ts);

void

next

_pos

ition

() r

aise

s(N

oMor

eEle

men

ts);

...}; in

terf

ace

Set

: C

olle

ctio

n {

Set

crea

te_u

nion

(in S

et o

ther

_set

);... bo

olea

nis

_sub

set_

of(in

Set

oth

er_s

et);

...}; in

terf

ace

Bag

: C

olle

ctio

n {

unsi

gned

long

occu

rren

ces_

of(in

any

ele

men

t);

Bag

crea

te_u

nion

(in B

ag o

ther

_bag

);...

}; inte

rfac

e Li

st :

Col

lect

ion

{ex

cept

ion

Inva

lid_I

ndex

{uns

igne

d_lo

ng in

dex;

};

void

rem

ove_

elem

ent_

at(in

uns

igne

d lo

ng p

ositi

on)

rais

es(I

nval

idIn

dex)

;an

yre

trie

ve_e

lem

ent_

at(in

uns

igne

d lo

ng p

ositi

on)

rais

es(I

nval

idIn

dex)

;vo

idre

plac

e_el

emen

t_at

(in a

ny e

lem

ent,

in u

nsig

ned

long

pos

ition

)ra

ises

(Inv

alid

Inde

x);

void

inse

rt_e

lem

ent_

afte

r(in

any

ele

men

t, in

uns

igne

d lo

ng p

ositi

on)

rais

es(I

nval

idIn

dex)

;... vo

idin

sert

_ele

men

t_fir

st(in

any

ele

men

t);

... void

rem

ove_

first

_ele

men

t()

rais

es(I

nval

idIn

dex)

;... an

yre

trie

ve_f

irst_

elem

ent(

) ra

ises

(Inv

alid

Inde

x);

... List

conc

at(in

Lis

t oth

er_l

ist)

;vo

idap

pend

(in L

ist o

ther

_lis

t);

}; inte

rfac

e A

rray

: C

olle

ctio

n {

exce

ptio

nIn

valid

_Ind

ex{u

nsig

ned_

long

inde

x; }

;vo

idre

mov

e_el

emen

t_at

(in u

nsig

ned

long

inde

x)ra

ises

(Inv

alid

Inde

x);

any

retr

ieve

_ele

men

t_at

(in u

nsig

ned

long

inde

x)

rais

es(I

nval

idIn

dex)

;vo

idre

plac

e_el

emen

t_at

(in u

nsig

ned

long

inde

x, in

any

ele

men

t)ra

ises

(Inv

alid

Inde

x);

void

resi

ze(in

uns

igne

d lo

ng n

ew_s

ize)

;}; st

ruct

Ass

ocia

tion

{any

key

; any

val

ue; }

;

inte

rfac

e D

ictio

nary

: C

olle

ctio

n {

exce

ptio

nK

eyN

otF

ound

{any

key

; };

void

bind

(in a

ny k

ey, i

n an

y va

lue)

;vo

idun

bind

(in a

ny k

ey)

rais

es(K

eyN

otF

ound

);an

ylo

okup

(in a

ny k

ey)

rais

es(K

eyN

otF

ound

);bo

olea

nco

ntai

ns_k

ey(in

any

key

);};

Figure 12.1c Overview of the interface definitions for part of the ODMG

object model. Interface definitions for collection objects.


Object

Iterator Collection Date Time Interval

Set List Bag Array Dictionary

Timestamp

Figure 12.2 Inheritance hierarchy for thebuilt-in interfaces of the object model.


class Employee( extent all_employees

key ssn ){

attribute string name;attribute string ssn;attribute date birthdate;attribute enum Gender{M, F} sex;attribute short age;relationship Department works_for

inverse Department::has_emps;void reassign_emp(in string new_dname)

raises(dname_not_valid);};

class Department( extent all_departments

key dname, dnumber ){

attribute string dname;attribute short dnumber;attribute struct Dept_Mgr {Employee manager, date startdate}

mgr;attribute set<string> locations;attribute struct Projs {string projname, time weekly_hours}

projs;relationship set<Employee> has_emps inverse Employee::works_for;void add_emp(in string new_ename) raises(ename_not_valid);void change_manager(in string new_mgr_name; in date startdate);

};

Figure 12.3 The attributes, relationships,and operations in a class definition.


interface ObjectFactory {Object new();

};

interface DateFactory : ObjectFactory {exception InvalidDate{};...Date calendar_date( in unsigned short year,

in unsigned short month,in unsigned short day)

raises(InvalidDate);...Date current();

};

interface DatabaseFactory {Database new();

};

interface Database {void open(in string database_name);void close();void bind(in any some_object, in string object_name);Object unbind(in string name);Object lookup(in string object_name)

raises(ElementNotFound);...

};

Figure 12.4 Interfaces to illustrate factory objects and database objects.


Interface

Class

Relationships

Person-IF

Student

1.1

1:N

M:N

Inheritance Interface (is-a)inheritanceusing “:”

Classinheritanceusing extends

Figure 12.5 An example of a database schema. (a) Graphical notationfor representing ODL schemas.


Person Department

Section

Course

has_majors offers

majors_in

completed_sections

offered_by

has_sections

students

of_course

registered_students

registered_in

committee

advisoradvises

on_committee_of

Faculty

GradStudent

Student

CurrSection

has_faculty

works_in

Figure 12.5 An example of a database schema. (b) A graphical objectdatabase schema for part of the UNIVERSITY database.


clas

s P

erso

n(

exte

nt

pers

ons

key

ssn

){

attr

ibu

test

ruct

Pna

me

{str

ing

fnam

e, s

trin

g m

nam

e, s

trin

g m

nam

e }

nam

e;at

trib

ute

stri

ng

ssn;

attr

ibu

ted

ate

birt

hdat

e;at

trib

ute

en

um

Gen

der{

M, F

}se

x;at

trib

ute

stru

ct A

ddre

ss {

sho

rt n

o, s

trin

g s

tree

t, sh

ort

apt

no,

stri

ng

city

, str

ing

sta

te, s

ho

rt z

ip }

addr

ess;

sho

rt a

ge()

;}; cl

ass

Fac

ulty

ext

end

s P

erso

n(

exte

nt

facu

lty

){

attr

ibu

test

rin

g

rank

;at

trib

ute

flo

atsa

lary

;at

trib

ute

stri

ng

offic

e;at

trib

ute

stri

ng

phon

e;re

lati

on

ship

Dep

artm

ent

wor

ks_i

n in

vers

e D

epar

tmen

t::ha

s_fa

culty

;re

lati

on

ship

set<

Gra

dStu

dent

> a

dvis

es in

vers

e G

radS

tude

nt::a

dvis

or;

rela

tio

nsh

ipse

t<G

radS

tude

nt>

on_

com

mitt

ee_o

fin

vers

e G

radS

tude

nt::c

omm

ittee

;vo

idgi

ve_r

aise

(in

flo

at r

aise

);vo

idpr

omot

e(in

str

ing

new

_ran

k);

}; clas

s G

rade

(ex

ten

tgr

ades

)

{at

trib

ute

en

um

Gra

deV

alue

s{A

,B,C

,D,F

,I,P

}gr

ade;

rela

tio

nsh

ipS

ectio

n se

ctio

n in

vers

e S

ectio

n::s

tude

nts;

rela

tio

nsh

ipS

tude

nt s

tude

nt in

vers

e S

tude

nt::c

ompl

eted

_sec

tions

;}; cl

ass

Stu

dent

ext

end

s P

erso

n(

exte

nt

stud

ents

)

{at

trib

ute

stri

ng

clas

s;at

trib

ute

Dep

artm

ent

min

ors_

in;

rela

tio

nsh

ipD

epar

tmen

t maj

ors_

in in

vers

e D

epar

tmen

t::ha

s_m

ajor

s;re

lati

on

ship

set<

Gra

de>

com

plet

ed_s

ectio

ns in

vers

e G

rade

::stu

dent

;re

lati

on

ship

set<

Cur

rSec

tion>

reg

iste

red_

inin

vers

e C

urrS

ectio

n::r

egis

tere

d_st

uden

ts;

void

chan

ge_m

ajor

(in

str

ing

dna

me)

rai

ses(

dnam

e_no

t_va

lid);

flo

atgp

a();

void

regi

ster

(in

sh

ort

sec

no)

rais

es(s

ectio

n_no

t_va

lid);

void

assi

gn_g

rade

(in

sh

ort

sec

no; i

n G

rad

eVal

ue

grad

e)ra

ises

(sec

tion_

not_

valid

,gra

de_n

ot_v

alid

);};

Figure 12.6 Possible ODL schema for theUNIVERSITY database of Figure 12.5(b).


clas

s D

egre

e{

attr

ibu

test

rin

g

colle

ge;

attr

ibu

test

rin

gde

gree

;at

trib

ute

stri

ng

year

;}; cl

ass

Gra

dStu

dent

ext

end

s S

tude

nt(

exte

nt

grad

_stu

dent

s )

{at

trib

ute

set<

Deg

ree>

degr

ees;

rela

tio

nsh

ipF

acul

ty a

dvis

or in

vers

e F

acul

ty::a

dvis

es;

rela

tio

nsh

ipse

t<F

acul

ty>

com

mitt

ee in

vers

e F

acul

ty::o

n_co

mm

ittee

_of;

void

assi

gn_a

dvis

or(i

n s

trin

g ln

ame;

in s

trin

g fn

ame)

rais

es(f

acul

ty_n

ot_v

alid

);vo

idas

sign

_com

mitt

ee_m

embe

r(in

str

ing

lnam

e; in

str

ing

fnam

e)ra

ises

(fac

ulty

_not

_val

id);

}; clas

s D

epar

tmen

t(

exte

nt

depa

rtm

ents

)

{at

trib

ute

stri

ng

dnam

e;at

trib

ute

stri

ng

dpho

ne;

attr

ibu

test

rin

gdo

ffice

;at

trib

ute

stri

ng

colle

ge;

attr

ibu

teF

acul

tych

air;

rela

tio

nsh

ipse

t<F

acul

ty>

has

_fac

ulty

inve

rse

Fac

ulty

::wor

ks_i

n;re

lati

on

ship

set<

Stu

dent

> h

as_m

ajor

s in

vers

e S

tude

nt::m

ajor

s_in

;re

lati

on

ship

set<

Cou

rse>

offe

rs in

vers

e C

ours

e::o

ffere

d_by

;}; cl

ass

Cou

rse

(ex

tent

cour

ses

){

attr

ibu

test

rin

gcn

ame;

attr

ibu

test

rin

gcn

o;at

trib

ute

stri

ng

desc

riptio

n;re

lati

on

ship

set<

Sec

tion>

has

_sec

tions

inve

rse

Sec

tion:

:of_

cour

se;

rela

tio

nsh

ipse

t<D

epar

tmen

t> o

ffere

d_by

inve

rse

Dep

artm

ent::

offe

rs;

}; clas

s S

ectio

n(

exte

ntse

ctio

ns

){

attr

ibu

tesh

ort

secn

o;at

trib

ute

stri

ng

year

;at

trib

ute

en

um

Qua

rter

{Fal

l, W

inte

r, S

prin

g, S

umm

er}

qtr;

rela

tio

nsh

ipse

t<G

rade

> s

tude

nts

inve

rse

Gra

de::s

ectio

n;re

lati

on

ship

Cou

rse

of_c

ours

e in

vers

e C

ours

e::h

as_s

ectio

ns;

}; clas

s C

urrS

ectio

n ex

ten

ds

Sec

tion

(ex

tent

curr

ent_

sect

ions

){

rela

tio

nsh

ip s

et<

Stu

dent

> r

egis

tere

d.st

uden

ts in

vers

e S

tude

nt::r

egis

tere

d_in

void

regi

ster

_stu

dent

(in

str

ing

ssn

)

rai

ses(

stud

ent_

not_

valid

, sec

tion_

not_

valid

, sec

tion_

full)

;};

Figure 12.6 Possible ODL schema for theUNIVERSITY database of Figure 12.5(b).


GeometryObject

Rectangle Triangle Circle ...

Figure 12.7a An illustration of interface inheritance via “:”.Graphical schema representation.


inte

rfac

e G

eom

etry

Obj

ect

{at

trib

ute

enu

m S

hape

{Rec

tang

le,T

riang

le,C

ircle

,...}

sha

pe;

attr

ibu

test

ruct

Poi

nt {

sho

rt x

, sh

ort

y}

refe

renc

e_po

int;

flo

atpe

rimet

er()

;fl

oat

area

();

void

tran

slat

e(in

sh

ort

x_t

rans

latio

n; in

sh

ort

y_t

rans

latio

n);

void

rota

te(i

n f

loat

ang

le_o

f_ro

tatio

n);

}; clas

s R

ecta

ngle

: G

eom

etry

Obj

ect

(ex

ten

tre

ctan

gles

){

attr

ibu

test

ruct

Poi

nt {

sho

rt x

, sh

ort

y}

refe

renc

e_po

int;

attr

ibu

tesh

ort

leng

th;

attr

ibu

tesh

ort

heig

ht;

attr

ibu

te

flo

ator

ient

atio

n_an

gle;

}; clas

s T

riang

le :

Geo

met

ryO

bjec

t(

exte

nt

tria

ngle

s )

{at

trib

ute

stru

ct P

oint

{sh

ort

x, s

ho

rt y

}re

fere

nce_

poin

t;at

trib

ute

sho

rtsi

de_1

;at

trib

ute

sho

rtsi

de_2

;at

trib

ute

fl

oat

side

1_si

de2_

angl

e;at

trib

ute

fl

oat

side

1_or

ient

atio

n_an

gle;

}; clas

s C

ircle

: G

eom

etry

Obj

ect

(ex

ten

tci

rcle

s

){

attr

ibu

test

ruct

Poi

nt {

sho

rt x

, sh

ort

y}

refe

renc

e_po

int;

attr

ibu

tesh

ort

radi

us;

}; ...

Figure 12.7b An illustration of interface inheritance via “:”.Corresponding interface and class definitions in ODL.


stru

ct E

nam

e {

d_S

trin

gfn

ame;

d_S

trin

gm

nam

e;d_

Str

ing

lnam

e;}; st

ruct

Add

ress

{d_

US

hort

no;

d_S

trin

gst

reet

;d_

US

hort

aptn

o;d_

Str

ing

city

;d_

Str

ing

stat

e;d_

US

hort

zip;

}; clas

s P

erso

n : p

ublic

d_O

bjec

t {pu

blic

://

Attr

ibut

esE

nam

een

ame;

d_S

trin

g ss

n;d_

Dat

ebi

rthd

ate;

enum

Gen

der

{M,F

}se

x;A

ddre

ssad

dres

s;//

Ope

ratio

nsP

erso

n(co

nst c

har

* pn

ame)

;d_

US

hort

age

;//

Ext

ent

stat

ic d

_Set

<d_

Ref

<P

erso

n>>

pers

ons;

stat

ic c

onst

cha

r *

cons

tex

tent

_nam

e;}; cl

ass

Fac

ulty

: pub

lic P

erso

n {

publ

ic:

// A

ttrib

utes

d_S

trin

gra

nk;

d_F

loat

sala

ry;

d_S

trin

gof

fice;

d_S

trin

gph

one;

// R

elat

ions

hips

(sy

ntax

is O

DM

G 1

.1 c

ompl

iant

)d_

Ref

<D

epar

tmen

t>w

orks

_in

inve

rse

Dep

artm

ent::

has_

facu

lty;

d_S

et<

d_R

ef<

Gra

dStu

dent

>>

ad

vise

sin

vers

e G

radS

tude

nt::a

dvis

or;

d_S

et<

d_R

ef<

Gra

dStu

dent

>>

on_

com

mitt

ee_o

fin

vers

e G

radS

tude

nt::c

omm

ittee

;//

Ope

ratio

nsF

acul

ty(c

onst

cha

r *

fnam

e, d

_Flo

at s

alar

y);

void

giv

e_ra

ise(

in d

_Flo

at r

aise

);vo

id p

rom

ote(

in d

_Str

ing

new

_ran

k);

// E

xten

tst

atic

d_S

et<

d_R

ef<

Fac

ulty

>>

facu

lty;

stat

ic c

onst

cha

r *

cons

tex

tent

_nam

e;};

Figure 12.8a Example illustrating O2. Defining part of theUNIVERSITY schema using the C++ O2 binding.


// Faculty Class

const char * const Faculty::extent_name = "faculty";

// Faculty constructor hereFaculty::Faculty(const char * fname, d_Float fsalary) :

Person(fname) {

salary = fsalary;// Put this new faculty into the extensionfaculty->insert_element(this);

}

void Faculty::give_raise(d_Float raise);{

salary += raise;}

void Faculty::promote(d_String new_rank);{

rank = new_rank;}

Figure 12.8b Example illustrating O2. C++ O2schema implementation for the Faculty class.


/* th

is is

the

file

univ

_sch

ema.

H th

at in

clud

es th

e da

taba

se c

lass

dec

lara

tions

*/

stru

ct P

hone

{in

t are

a_co

de ;

int n

umbe

r ;

} stru

ct D

ate

{in

t yea

r ;

int m

onth

;in

t day

;} cl

ass

Per

son

{pu

blic

:ch

ar s

sn[9

] ;st

ruct

{ch

ar*

first

nam

e ;

char

* m

iddl

enam

e ;

char

* la

stna

me

;}

nam

e ;

stru

ct {

int

n

umbe

rch

ar*

stre

et ;

char

* ap

t_no

;ch

ar*

city

;ch

ar*

stat

e ;

char

* zi

pcod

e ;

} ad

dres

s ;

Dat

e bi

rthd

ate

;ch

ar s

ex ;

int a

ge (

) ;

} stru

ct T

rans

crip

t {ch

arflo

at

Sec

tion

} clas

s S

tude

nt: p

ublic

Per

son

{

/* S

tude

nt in

herit

s (

is d

eriv

ed fr

om)

Per

son

*/ p

ublic

:ch

ar*

Dep

artm

ent

Dep

artm

ent

os_S

et<

Sec

tion*

>os

_Set

<T

rans

crip

t*>

float

gra

de_p

oint

_ave

rage

()

;vo

id c

hang

e_cl

ass

() ;

void

cha

nge_

maj

or (

Dep

artm

ent *

new

_maj

or)

;} st

ruct

Deg

ree

{ch

ar*

colle

ge ;

char

* de

gree

;in

t

yea

r ;

} clas

s G

rad_

stud

ent:

publ

ic S

tude

nt {

/* G

rad_

stud

ent i

nher

its (

is d

eriv

ed fr

om)

Stu

dent

*/p

ublic

:

os

_Set

<D

egre

e*>

deg

rees

;

F

acul

ty

*

advi

sor

;} cl

ass

Fac

ulty

: pub

lic P

erso

n {

/*

Fac

ulty

inhe

rits

(is

der

ived

from

) P

erso

n */

float

ch

ar*

char

*ch

ar*

os_S

et<

Dep

artm

ent*

>D

epar

tmen

tos

_Set

<G

rant

*>os

_Set

<S

tude

nt*>

void

pro

mot

e_fa

culty

()

;vo

id g

ive_

rais

e (f

loat

per

cent

) ;

}

Figure 12.9 ObjectStore C++ classdeclarations for part of the UNIVERSITY database.


Figure 12.9 (continued)

stru

ct D

egre

e {

char

* co

llege

;ch

ar*

degr

ee ;

int

y

ear

;} cl

ass

Gra

d_st

uden

t: pu

blic

Stu

dent

{

/*

Gra

d_st

uden

t inh

erits

(is

der

ived

from

) S

tude

nt *

/pub

lic :

os_S

et<

Deg

ree*

>

d

egre

es ;

Fac

ulty

*ad

viso

r ;

} clas

s F

acul

ty: p

ublic

Per

son

{

/* F

acul

ty in

herit

s (

is d

eriv

ed fr

om)

Per

son

*/flo

at

sala

ry;

char

*ra

nk;

char

*fo

ffice

;ch

ar*

fpho

ne;

os_S

et<

Dep

artm

ent*

>be

long

s_to

;D

epar

tmen

t*c

hairs

;os

_Set

<G

rant

*>gr

ants

;os

_Set

<S

tude

nt*>

advi

ses;

void

pro

mot

e_fa

culty

()

;vo

id g

ive_

rais

e (f

loat

per

cent

) ;

} clas

s D

epar

tmen

t {ch

ar*

dnam

e;ch

ar*

offic

e;P

hone

dpho

ne;

os_S

et<

Fac

ulty

*>m

embe

rs;

os_S

et<

Stu

dent

*>m

ajor

s;F

acul

tych

airp

erso

n;os

_Set

<C

ours

e*>

cour

ses;

void

add

_maj

or (

Stu

dent

*s)

;vo

id r

emov

e_m

ajor

(S

tude

nt *

s) ;

}


extern database *univ_db ;

class Person ;

class Faculty: public Person { /* Faculty inherits (is derived from) Person */float salary ;char* rank ;char* foffice ;char* fphone ;os_Set<Department*> belongs_to

inverse_member Department::members ;Department *chairs

inverse_member Department::chairperson ;os_Set<Grant*> grants ;os_Set<Student*> advises ;

Faculty (char s[9]) { ssn = new (univ_db) char[9] ; strcpy(ssn, s) ; }/* the ssn attribute is inherited from Person */

void promote_faculty () ;void give_raise (float percent) ;

}

class Department {char*char*Phoneos_Set<Faculty*> members

inverse_member Faculty::belongs_to ;os_Set<Student*> majors ;Faculty *chairperson

inverse_member Faculty::chairs ;os_Set<Course*> courses ;

Department (char* d) { dname = new (univ_db) char[strlen(d)+1] ; strcpy(dname, d) ; }void add_faculty (Faculty *f) ;void add_major (Student *s) ;int remove_major (Student *s) ;

}

dname ;office ;dphone ;

Figure 12.10 Declaring inverse relationships in ObjectStore C++.


(a)int Person::age () {

Date d = today() ; int a = d.year - birthdate.year ;if ( d.month < birthdate.month ) ll ( d.month == birthdate.month ) && ( d.day < birthdate.day ) ) --a ;return a;

} ;

float Student::grade_point_average () {float sum = 0.0 ; int count = 0 ; Transcript* t ;foreach (t, transcript) {

sum += t->ngrade ; ++count ; /* increments sum by ngrade, count by 1 */}

return sum/count ;} ;

void Student::change_major (Department *new_major) {majors_in = new_major ; }void Department::remove_major (Student *s) {majors->remove(s) ; }void Department::add_faculty (Faculty *f) { members->insert (f) ; }void Department::add_major (Student* s) { majors->insert(s) ; }

(b)main () {

database *univ_db = database::open ("/database/univ" ) ;

transaction::begin () ;/* create two persistent sets to hold all Faculty and all Department objects *

os_Set<Faculty*> &all_faculty = os_Set<Faculty*>::create(univ_db) ;os_Set<Department*> &all_depts = os_Set<Department*>::create(univ_db) ;

/* create a new Faculty object and a new Department object using the constructors */Faculty *f = new (univ_db) Faculty ("123456789") ;Department *d = new (univ_db) Department ("Computer Science") ;

/* relate the objects by invoking the appropriate method */d->add_faculty (f) ;

/* add the objects to their persistent sets */all_faculty.insert(f) ; all_depts.insert(d) ;

transaction::commit () ;}

Figure 12.11 ObjectStore C++ programming.(a) Code for some of the member functions (operations)

in Figure 12.9. (b) Creating persistent objects.


os_Set<Faculty*> &asst_profs =all_faculty [: rank == 'Assistant Professor' :]

os_Set<Faculty*> &rich_asst_profs =all_faculty [: rank == 'Assistant Professor' && salary > 5000.00 :]

os_Set<Faculty*> &dept_chairs =all_faculty [: chairs :]

os_Set<Faculty*> &cs_faculty =all_faculty [: belongs_to [: dname == 'Computer Science' :] :]

Figure 12.12 Queries in ObjectStore ++.


IDLStubs DII

Control Control

ORBInterface

Object Request Broker

IDLSkeleton

DSI

*Really the Basic Object Adaptor

Object Adapter*

TargetObjectClient

Figure 12.13 The CORBA 2.0 ORB Architecture. Pearson Education Ltd. from CORBA Distributed Objects by Sean Baker © 1997 Addison Wesley Longman.


Application Objects

Application Object

CORBA Services CORBA Facilities

Object Request Broker

Figure 12.14 The CORBA Object Management Architecture (OMA).Pearson Education Ltd. from CORBA Distributed Objects by Sean Baker © 1997 Addison Wesley Longman.

figure 12 - cs.boisestate.educs.boisestate.edu/~jhyeh/cs410/cs410_bookfigures_ch12.pdf · ©...

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