Software Design 2e - DIM

More documents

Recommendations

Info

14.3 The JSP process293The process part of JSP consists of five principal steps that are performed in sequence(although of course, as with all design problems, there will be iterations betweenthese). The tasks performed in these steps can be summarized as follows.1. Draw a Structure Diagram that describes each of the input and output datastreams.2. Merge these to form the program Structure Diagram.3. List the operations that need to be performed by the program, and allocate eachoperation to an element in the program Structure Diagram.4. Convert the program to text without specific conditions for any of the decisionpoints.5. Add the conditions used for each iteration and selection operation.The JSP processAs this shows, the JSP design method is based on a strategy of producing a programstructure that reflects the structure of the task itself. This structure is therefore basedlargely on consideration of algorithmic forms, and the JSP design process does notaddress issues of modularity, such as allocation to constructional units.The first two steps are major ones, and may well require about half of the totaldesign effort. While step 1 may seem relatively mechanical in nature, it is not necessarilyso, and step 2 is far from simple. As a check on the results of step 2, expertsgenerally consider that any problems encountered in performing the tasks of step 3(allocation of operations) are likely to indicate that the structure produced by step 2is not correct. JSP also incorporates a useful verification procedure that can be used tocheck that the structures generated by step 2 are consistent with those produced bystep 1.As already mentioned, JSP is unusual in that it uses only a single diagrammaticalform of description. However, the transformation diagram in Figure 14.3 shows thatthis is perhaps misleading, since while the form of diagram used remains the same, theinterpretation of it changes as a result of the transformation performed in step 2.Indeed, part of the complexity of step 2 is that it involves a transformation from astatic model of sequential ordering of data elements to a dynamic model of timeorderedsequencing of program actions.To illustrate the basic design process more fully, we will work through a shortexample of the use of JSP, concentrating on steps 1 to 3 of the design process, since itis these that form the major components of the method.Since JSP is often (unfairly) associated only with ‘classical’ data-processing problemsbased on handling files, with the final structures expressed in COBOL, the exampleproblem has been chosen to look as unlike this as possible. The basic systemrequirement is as follows:A petrol filling station (shown schematically in Figure 14.4) has a number of selfservicepumps, each of which can be used to dispense both diesel fuel and unleadedpetrol. There is a small local computer in each pump that maintains the display of
294Jackson Structured Programming (JSP)Figure 14.3The JSP design process.
Page 2 and 3:
Software Design
Page 4 and 5:
Software DesignDavid Budgen
Page 7 and 8:
viContentsChapter 4 Design Qualitie
Page 9 and 10:
viiiContentsChapter 16 Designing wi
Page 11 and 12:
xPreface to the second editiondescr
Page 13 and 14:
xiiPreface to the First EditionWhy
Page 15 and 16:
xivPreface to the first editionto t
Page 17 and 18:
xviPublisher’s AcknowledgementsWe
Page 20 and 21:
chapter 13The Nature of the Design
Page 22 and 23:
Design is just as important with so
Page 24 and 25:
Initialobservations7More systematic
Page 26 and 27:
development. However, it should als
Page 28 and 29:
From this relatively simple case st
Page 30 and 31:
nnWhere possible, the panels used i
Page 32 and 33:
It might well be argued that while
Page 34 and 35:
system being developed. Clearly, in
Page 36 and 37:
case study, the outline plan on squ
Page 38 and 39:
nnnWicked problems do not have an e
Page 40:
on to Pittsburgh. Airline B is the
Page 43 and 44:
262.1 What is software?The software
Page 45 and 46:
28nChangeability. Software suffers
Page 47 and 48:
30The software design processFigure
Page 49 and 50:
32The software design processthat a
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
38The software design processproces
Page 57 and 58:
40The software design processform p
Page 59 and 60:
Page 61 and 62:
44The software design process2.3 De
Page 63 and 64:
463.1 A context for designDesign in
Page 65 and 66:
48Design in the software developmen
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
54A personal itchDesign in the soft
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
60nthe associated role of requireme
Page 80 and 81:
chapter 463Design Qualities4.1 The
Page 82 and 83:
is virtually impossible to modify i
Page 84 and 85:
measurable characteristic that can
Page 86 and 87:
69Assessing design qualityFigure 4.
Page 88 and 89:
nnnnreliabilityefficiencymaintainab
Page 90 and 91:
Table 4.1The cognitive dimensions73
Page 92 and 93:
system. The results of this study u
Page 94 and 95:
nnnmodules are easy to replace;each
Page 96 and 97:
Table 4.3The principal forms of coh
Page 98 and 99:
Identifying attributes that are the
Page 100 and 101:
Our study of the nature of the desi
Page 102:
nTechnical design reviews can provi
Page 106 and 107:
chapter 589Describing a Design Solu
Page 108 and 109:
91Figure 5.1Example of a ‘physica
Page 110 and 111:
term is used to describe ‘stakeho
Page 112 and 113:
95Design viewpoints for softwareFig
Page 114 and 115:
nnof mark-up languages such as HTML
Page 116 and 117:
nnntextdiagramsmathematical express
Page 118 and 119:
happens with pioneering ideas, it h
Page 120:
I have termed ‘derived viewpoints
Page 123 and 124:
1066.1 The need to share knowledgeT
Page 125 and 126:
108Transferring design knowledge6.1
Page 127 and 128:
110then briefly consider how the co
Page 129 and 130:
112Transferring design knowledgethe
Page 131 and 132:
114Transferring design knowledge6.2
Page 133 and 134:
116mainTransferring design knowledg
Page 135 and 136:
118Transferring design knowledgennn
Page 137 and 138:
120Transferring design knowledgeOne
Page 139 and 140:
1226.5 A unified interpretation?Tra
Page 141 and 142:
124Transferring design knowledgeA s
Page 144 and 145:
chapter 7127Some Design Representat
Page 146 and 147:
Table 7.1The selection of black box
Page 148 and 149:
131Black box notationsFigure 7.1A f
Page 150 and 151:
133Black box notationsFigure 7.3mac
Page 152 and 153:
135Black box notationsFigure 7.4A
Page 154 and 155:
nattributes are classes of values t
Page 156 and 157:
The ERD viewpointERDs are purely an
Page 158 and 159:
Page 160 and 161:
7.2.4 The StatechartLike the STD th
Page 162 and 163:
145Black box notationsFigure 7.13St
Page 164 and 165:
7.2.5 The Jackson Structure Diagram
Page 166 and 167:
149Black box notationsFigure 7.17 A
Page 168 and 169:
Page 170 and 171:
153Figure 7.21The UML class notatio
Page 172 and 173:
155Use case (title indicates the ac
Page 174 and 175:
157cardrejectedprocesscardcard acce
Page 176 and 177:
159White box notationsFigure 7.27A
Page 178 and 179:
only the presence of the latter is
Page 180 and 181:
In its most simple form, such a com
Page 182 and 183:
NarrativeUser starts web browserUse
Page 184 and 185:
If anything, pseudocode is used rat
Page 186 and 187:
Many notations can be conveniently
Page 188 and 189:
171Developing a diagramFigure 7.38E
Page 190 and 191:
Stevens P. with Pooley R. (2000). U
Page 192 and 193:
chapter 8175The Rationale for Metho
Page 194 and 195:
provide a methodological analysis o
Page 196 and 197:
179Figure 8.2nnSome properties of f
Page 198 and 199:
ones that may be usefully supported
Page 200 and 201:
183Figure 8.3The use of virtual mac
Page 202 and 203:
In particular, the use of a design
Page 204 and 205:
need to be recognized. Unfortunatel
Page 206 and 207:
A somewhat different approach to cl
Page 208:
Exercises1918.1 How would you class
Page 211 and 212:
1949.1 The role of strategy in meth
Page 213 and 214:
196Design processes and design stra
Page 215 and 216:
Page 217 and 218:
Page 219 and 220:
Page 221 and 222:
Page 223 and 224:
Page 225 and 226:
Page 227 and 228:
Page 229 and 230:
212ExercisesDesign processes and de
Page 231 and 232:
21410.1 Design by template and desi
Page 233 and 234:
216Design patternspatterns for obje
Page 235 and 236:
218Design patternsFigure 10.1A simp
Page 237 and 238:
220Design patternsnnnnnnnnnnnName u
Page 239 and 240:
222Design patternsFigure 10.3The pr
Page 241 and 242:
224ClientRequesthandlerDesign patte
Page 243 and 244:
226Design patternsout how to produc
Page 245 and 246:
2281Design patternsRequirementsPatt
Page 247 and 248:
230Design patternsThe patterns comm
Page 250 and 251:
chapter 11233Stepwise Refinement11.
Page 252 and 253:
2. The degree of modularity resulti
Page 254 and 255:
compiler237lexical analysisFigure 1
Page 256:
Further reading239Wirth N. (1971).
Page 259 and 260: 24212.1 Black box to white box in s
Page 261 and 262: 244well be to deliver a solution on
Page 263 and 264: 246Incremental designpossible model
Page 265 and 266: 248Incremental designnnthe roles, r
Page 267 and 268: 250Incremental designFunctionalityT
Page 269 and 270: 252Incremental designBusinessstudyF
Page 271 and 272: 254Incremental designalthough it ma
Page 273 and 274: 256ExercisesIncremental design12.1
Page 275 and 276: 25813.1 Origins, development and ph
Page 277 and 278: 260Structured systems analysis and
Page 305 and 306: 288ExercisesStructured systems anal
Page 307 and 308: 29014.1 Some background to JSPJacks
Page 309: 292Jackson Structured Programming (
Page 313 and 314: 296Jackson Structured Programming (
Page 332 and 333: chapter 15315Jackson System Develop
Page 334 and 335: 317The JSD modelFigure 15.1Top-leve
Page 336 and 337: 319Figure 15.3Generic form of ESD.t
Page 338 and 339: 321Figure 15.6Process 1.The SSD for
Page 340 and 341: 323The JSD processFigure 15.9 The J
Page 342 and 343: Entity analysis (the entity-action
Page 344 and 345: 327The JSD processFigure 15.13The J
Page 346 and 347: 329The JSD processFigure 15.14 The
Page 348 and 349: 331The JSD processFigure 15.15 The
Page 350 and 351: 333The JSD processFigure 15.16The c
Page 352 and 353: Information function step335From a
Page 354 and 355: The situation is analogous to that
Page 356: Exercises33915.1 Construct an ESD t
Page 359 and 360: 34216.1 The ‘object concept’Des
Page 361 and 362:
344Designing with objectsThe evolut
Page 363 and 364:
346Designing with objectsFigure 16.
Page 365 and 366:
348Designing with objectsFor the ob
Page 367 and 368:
Page 369 and 370:
352 Executable units of code(subpro
Page 371 and 372:
354A summary of the core concepts o
Page 373 and 374:
356Designing with objectsnnnnnnnorg
Page 375 and 376:
358Designing with objectsA rather l
Page 377 and 378:
360Designing with objects16.2.1 Sur
Page 379 and 380:
Page 381 and 382:
364closely at the representation pa
Page 383 and 384:
366Designing with objectsAn empiric
Page 385 and 386:
368Designing with objectsof a frame
Page 387 and 388:
370Designing with objects16.3.2 Des
Page 389 and 390:
372Designing with objectsDepartment
Page 391 and 392:
Page 393 and 394:
376Designing with objects1. The obj
Page 395 and 396:
378Designing with objectsdescribe a
Page 397 and 398:
380Designing with objectsnnapproach
Page 399 and 400:
382Designing with objectssequence d
Page 401 and 402:
384Designing with objectsnnhow is t
Page 403 and 404:
386step, it is those analysis-relat
Page 405 and 406:
388Designing with objectsStep 7: De
Page 407 and 408:
390Designing with objectsbehaviour,
Page 409 and 410:
392indicate the degree of effort. A
Page 411 and 412:
394Designing with objectsThe UP wor
Page 413 and 414:
Page 415 and 416:
398Designing with objectsSimilarly,
Page 417 and 418:
400Designing with objectswww.omg.or
Page 419 and 420:
40217.1 The component conceptCompon
Page 421 and 422:
404Component-based designmore than
Page 423 and 424:
406Component-based designFigure 17.
Page 425 and 426:
408Component-based designto address
Page 427 and 428:
410Component-based designnto decomp
Page 429 and 430:
412Component-based design4. Archite
Page 431 and 432:
41417.3 Designing componentsCompone
Page 433 and 434:
416Component-based designSourceInde
Page 435 and 436:
418Component-based designwww.sei.ed
Page 437 and 438:
42018.1 The case for rigourA formal
Page 439 and 440:
422A formal approach to designmight
Page 441 and 442:
424A formal approach to designFigur
Page 443 and 444:
426A formal approach to design18.2.
Page 445 and 446:
428 Table 18.1 Set operations used
Page 447 and 448:
430A formal approach to designClear
Page 449 and 450:
432InitResSystA formal approach to
Page 451 and 452:
Page 453 and 454:
Page 455 and 456:
438A formal approach to designThis
Page 457 and 458:
44018.2 Write simple Z specificatio
Page 459 and 460:
44219.1 What is software now?Whithe
Page 461 and 462:
444Whither software design?Figure 1
Page 463 and 464:
446Whither software design?Figure 1
Page 465 and 466:
448Whither software design?Another
Page 468 and 469:
451BibliographyAbbott R.J. (1983).
Page 470 and 471:
Buxton J. and McDermid J. (1992). H
Page 472 and 473:
Guindon R. (1990). Designing the de
Page 474 and 475:
Perry D.E. and Wolf A.L. (1992). Fo
Page 476:
Ward P.T. and Mellor S.J. (1985). S
Page 479 and 480:
462IndexCcall and return (architect
Page 481 and 482:
464Indexgraphical user interface (G
Page 483 and 484:
466Indexprogram design 290program i
Page 485:
468WYIndexwalkthrough 81waterfall m
show all

Software Design 2e - DIM

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?