PHN 1:

TNG QUAN

CHNG 1:

TNG QUAN VCNG NGH PHN MM

Mc tiuNi dung

Mc tiu :

Cung cp cc khi nim c bn trong cng ngh phn mm.

Ni dung :

1. Lc s.2. Phn mm.3. Cng ngh phn mm.4. Cc qui trnh cng ngh.5. Cc phng php pht trin phn mm.6. Cc cng c v mi trng pht trin phn mm.7. Cc ni dung c bn ca cng ngh phn mm.

1.1 Lc s

Qua cc giai on :

Giai on I : Thi k th h th nht ca MTT ( Thp nin 50.)M t da vo cc c trng:

a) Quan im : Lp trnh l mt hot ng ngh thut, da trn cm tnh.

b) Ngn ng lp trnh : NN my, bc thp.c) Phng php lp trnh : Tuyn tnh.d) Nng sut : Thp

1.1 Lc s (tt)

Giai on th 2 :1. Thi k khng hong phn mm ( Trong thp nin 60 )Nguyn nhn:

- Chi ph phn mm cao.- Cc d n phn mm khng c c kt qu tt do phng php xy dng phn mm cm tnh, th s, thcng

2. Gii quyt khng hong:-Thay i quan im nghin cu , i tng nghin cu, phng php nghin cu, . . .

3. Cc thnh qu:- H tin chng minh tnh ng ca chng trnh (Hoare)- Phng php lun lp trnh cu trc.

. . .

1.1 Lc s (tt)

Giai on th 3 : ( T gia nhng nm 70 n nay ) :c trng : - H thng phn b - nhiu my tnh, mi my thc hin mt chc nng tng tranh v lin lc vi my khc.- S pht trin nhanh ca cc my tnh c nhn.

Giai on th 4 :c trng :

- Cng ngh phn mm hng i tng thay th nhiu cch tip cn pht trin phn mm.

- Phn mm vi kin trc tnh ton khc v c bn nh cc h chuyn gia, phn mm tr tu nhn to, mng Nron chuyn t th nghim vo ng dng thc t.

1.2. Phn mm (Software)

1. Khi nim.Phn mm l h thng cc chng trnh thc hin c trn my tnh nhm h tr cho cc nh chuyn mn trong tng lnh vc chuyn ngnh thc hin tt cc thao tc nghip v ca mnhLnh vc chuyn ngnh : Mi mt trong i sng x hi nh gio dc, quc phong, gii tr, kinh doanh, . . .Nh chuyn mn ( ngui s dng) : Ngi hoc b phn tham gia hot ng vo cc lnh vc tng ng.Thao tc nghip v : Cc cng vic trong th gii thc c chuyn vo lnh vc tng ng.

2. Cc c trng phn mm.- Khng hng, ch lc hu.- Lm theo n t hng, t khi lp rp t cc thnh phn c sn.

1.2. Phn mm (tt)

3. Cc thnh phn phn mm.a. Thnh phn giao din :- Tip nhn cc yu cu v vic s dng phn mm ca ngi s

dng ( nh chn cng vic,nhp d liu ngun, )- Trnh by kt qu phn mm thc hin.- iu khin phn mm hot ng.b. Thnh phn x l :

- Kim tra tnh hp l ca d liu ngun.- Tra cu, Tnh ton, bin i cho ra kt qu.

c. Thnh phn d liu:- T chc cu trc d liu.- T chc lu tr C s d liu.- Truy xut (c, ghi) d liu ).

1.2. Phn mm (tt).

4. Phn loi :a. Phn mm h thng.

c c trng bi : Tng tc ch yu vi phn cng, dng chung ti nguyn, . . .L tp cc chng trnh phc v cho cc chng trnh khc nh : trnh bin dch, cc trnh tin ch x l tp, H iu hnh. . .

b. Phn mm thi gian thc.C c trng rng buc cht ch vi thi gian. L cc phn mm c cc thnh phn :

- Thu thp d liu.- Phn tch.- Kim sot.- iu phi.Chng hn nh cc chng trnh tr chi, iu khin t ng,. . .

1.2. Phn mm (tt)

c. Phn mm nghip v.Cc phn mm h thng tin qun l.

d. Phn mm khoa hc v cng nghc c trng bi thut ton s nh cc chng trnh ti u,. . .

e. Phn mm nhng.Nm trong b nh ch c v c dng iu khin cc sn phm v h thng cho ngi dng.

f. Phn mm my tnh c nhn.Nh phn mm x l vn bn, bng tnh, . .

g. Phn mm tr tu nhn to :Dng cc thut ton phi s, nh cc h chuyn gia, mng nron nhn to, . . .

1.2. Phn mm (tt)

5. Cht lng phn mm (cc tiu chun phn mm) :a. Tnh ng n : Khng c s c, ng vi yu cu thit k.b. Tnh tin ha : C th thay i, m rng cc yu cu, chc nng ca

phn mm.c. Tnh tin dng : D hc, d s dng.d. Tnh hiu qu : Kinh t, tc , b nh.e. Tnh khoa hc : V ni dung, hnh thcf. Tnh c lp : c lp vi thit b, vi cu trc i tng phn mm

qun l.g. Tnh ton vn : C c ch ngn nga vic pht sinh d liu sai qui

cch, phc hi d liu, . . .. . .

1.2. Phn mm (tt).

6. Mt s thut ng lin quan:- Pht trin phn mm (Software development).

Tin trnh xy dng phn mm t khi bt u lp khoch d n phn mm cho n khi chuyn giao sn phm.

- ng dng (Application).Tp cc chng trnh thc hin t ng trn my tnh mt s nhim v.

- K s phn mm ( Software Engineer).Ngi p dng kin thc pht trin phn mm vo vic t chc xy dng mt cch c h thng cc ng dng.

- Ngi dng (User ).i tng s dng phn mm.

1.3. Cng ngh phn mm (Software Engineering )

1. nh ngha CNPM.Cng ngh :L cch s dng cc cng c, k thut trong vic gii quyt mt bi ton no .Cng ngh phn mm l ngnh khoa hc nghin cu cc nguyn l, cc phng php,cc cng c, cc th tc phc v cho vic xy dng cc phn mm c cht lng trong khong thi gian v chi ph hp l.

2. Cc i tng nghin cu ca CNPM.a. Qui trnh cng ngh phn mm

H thng cc giai on trong tin trnh pht trin phn mmb. Phng php pht trin phn mm :

H thng cc hng dn cho php thc hin mt giai on no trong qui trnh cng ngh.

c. Cng c v mi trng pht trin phn mm :Tp cc phn mm h tr tin trnh pht trin phn mm.

1.3. Cng ngh phn mm (Software Engineering) (tt)

3. Cc yu t trong CNPM.a. Con ngui :

Bao gm : Nh qun l, nh phn tch h thng, k s phn mm, ngi kim nh cht lng, lp trnh vin, ngi dng khch hng,Cu trc nhm tu theo quy m : nhm nh hot ng c hiu qukhong 5 8 ngi (tch hp cc kh nng c th h tr nhau).

b. D n PM : n v t chc, qun l vic pht trin phn mm.

c. Sn phm PM : u ra ca d n phn mm, c th l m hnh, m ngun, ti liu,. . .

d. Qui trnh cng ngh.e. Cng c.

S nh hng gia cc yu t :

1.3. Cng ngh phn mm (Software Engineering )(tt)

D N CON NGI

QUI TRNH

SN PHM

CNG C

1.4. Cc qui trnh cng ngh.( M hnh cc quy trnh pht trin phn mm)

1. M hnh tun t tuyn tnh ( Linear Sequential Model)( Cc tn gi khc :- M hnh thc nc (Waterfall Model)- Vng i c in (Classical life cycle) )

a. Xc nh yu cu bi ton .( m t dng vn bn).Mc tiu : Ch ra cc yu cu m phn mm phi xy dng.Kt qu tip nhn : Thng tin v cc hot ng ca th gii thc.Kt qu chuyn giao ( cho giai on sau ): - Danh sch cc yu cu.- Thng tin chi tit v cc yu cu.- Cc qui nh lin quan.

1.4. Cc qui trnh cng ngh (tt)

b. M hnh ha yu cu.( m t dng s ).Mc tiu : Ch ra cc yu cu m phn mm phi xy dng di dng m hnh ( M hnh th gii thc).Kt qu tip nhn : Kt qu chuyn giao ca giai on xc nh yu cu.Kt qu chuyn giao ( cho giai on sau ): - M hnh x l : H thng cc cng vic trong th gii thc cng vi quan h gia chng.- M hnh d liu : H thng thng tin cng vi quan h gia chng.- Cc m hnh khc. . .

1.4. Cc qui trnh cng ngh (tt)

c. Thit k phn mm :Mc tiu : To ra m hnh phn mm (cc thnh phn phn mm ).Kt qu tip nhn : M hnh th gii thc.Kt qu chuyn giao :- M t thnh phn giao din :- M t thnh phn x l.- M t thnh phn d liu.- M t kin trc phn mm.

1.4. Cc qui trnh cng ngh (tt)

d. M ha.Mc tiu : To ra phn mm ng theo yu cu.Kt qu tip nhn : M hnh phn mm.Kt qu chuyn giao :- M ngun chng trnh.- C s d liu tng ng.- Chng trnh ci t.- Chng trnh c dch, thi hnh c.

1.4. Cc qui trnh cng ngh (tt)

e. Kim chng.Mc tiu : Nng cao tin cy ca phn mm.Kt qu tip nhn : Phn mm, M hnh phn mm, danh sch cc yu cu.Kt qu chuyn giao :- Phn mm c khng nh v cht lng.

1.4. Cc qui trnh cng ngh (tt)

f. Bo tr :Mc tiu : Lm cho phn mm hot ng n nh hoc nng cp phn mm.Kt qu tip nhn : Phn mm, M hnh phn mm, danh sch cc yu cu.Kt qu chuyn giao :- Phn mm hot ng n nh.- Phn mm c nng cp.

1.4. Cc qui trnh cng ngh (tt)

( M hnh thc nc )

XYC

MHHYC

Thit k

M ho

Kim chng

Bo tr

1.4. Cc qui trnh cng ngh (tt)

2. M hnh to mu (Prototyping Model) :a. Tp hp yu cu : K s PM v khch hng cng xc

nh cc yu cu (c bit), cc qui nh lin quan.b. Thit k nhanh : Thit k nhng yu cu c bit

to mt bn mu s b.c. nh gi ca khch hng : Bn mu c khch hng

nh gi lm r thm cc yu cu khc ca h thng.d. Lm mn bn mu : Thit k li bn mu c khch

hng nh gi.

S :

1.4. Cc qui trnh cng ngh (tt)

( M hnh lm bn mu )

1.4. Cc qui trnh cng ngh (tt)

3. M hnh xon c ( Spiral Model )a. Xc nh mc tiu, gii php,rng buc .b. Phn tch ri ro.c. Pht trin phn mm.d. nh gi ca khch hng.

Mi ln lp xon c ( t trong ra ngoi ) ta li c mt phin bn thit k hon thin hn

S :

1.4. Cc qui trnh cng ngh (tt)

( M hnh xon c )

1.4. Cc qui trnh cng ngh (tt)

5. Nhn xt chung v cc qui trnh cng ngh.Tin trnh pht trin phn mm bao gm ba giai oan c bn :

* Giai on xc nh :Tp trung vo lm ci g ? , bao gm : Phn tch h thng, lp khoch d n, phn tch yu cu.

* Giai on pht trin :Tp trung vo lm th no ? , bao gm : Thit k, m ha, kim th.

* Giai on bo tr :Tp trung vo thay i ?, bao gm : Sa li, thch nghi, nng cao.

1.5. Cc phng php pht trin phn mm

C nhiu phng php pht trin phn mm, trong c 2 phng php thng c dng :

1. Phng php cu trc:Chc nng c phn r theo mt h thng cu trc.To ra cc m hnh chc nng, m hnh d liu,...u im:

n gin, d hiuNgi pht trin phn mm phn r c chc nng, thy c qutrnh hat ng ca phn mm.

Khuyt im:Khi chc nng b thay i s dn ti cu trc phn mm thay iS tch bit gia cc chc nng v d liu lm cho phi vit li m cho cc chc nng ging nhau nhng x l cc kiu d liu khc nhau.

1.5. Cc phng php pht trin phn mm

2. Phng php Hng i tng :Cu trc thng tin trong h thng thng tin l t thay iKhi nim i tng c dng m t thng tin. Gia cc i tng c th c quan h k tha.i tng: D liu Tc vu im:

Tng cng tnh ti s dng: Gia vo quan h k tha, lm gim chi ph xy dng liTng cng tnh m rng: Khng nh hng n cu trc thng tin do m rng chc nng c th thc hin qua vic to l con.

Khuyt im: Lnh vc ng dng (cu trc thng tin) thay i s dan ti xy dng li phn mm.

1.6. Cng c pht trin phn mm

H thng phn mm h tr qu trnh pht trin phn phn mm, hay trong tng giai on gi l CASE Tools( Computer Aided Software Engineering Tools) : Chc nng ca CASE trong mi giai on pht trin PM

-debug-Pht d liu th nghim, . . .

Kim th

-Son tho chng trnh-Trnh dch, . . .

M ha

-San tho s quan h-Pht sinh CSDL, . .

Thit k- Son tho s : DFD, ERD, . .Phn tch