CS 501: Software Engineering Fall 1999

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CS 501 Software EngineeringFall 1999
Lecture 18 (a) Project Reports (b)
Object-Oriented Design III
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Administration
? Recitation session Rational Rose
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Project Progress
? All projects are highly promising, some are
exceptional. ? Major concern is the time to
completion. ? Real life experiences Client
representative leaves suddenly Team member drops
course First approach not adequate (performance
of animation) ? Start-up delays learning,
studying technical options, access to
software and facilities, scheduling meetings
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Thinking for the Long Term
Believe that your software will be in use 5 years
from now. ? What happens at end of
semester? Packaging and hand-over Client's
technical preferences (C, Java) ? Some system
decisions based on short-term considerations ?
Which formats, protocols, etc. do you think will
last? (IIOP, RMI, SNMP, ...)
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Network Security
Server
Vulnerable information
Application
Internet
Database
Web server
SendMail
Insecure components
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Network Security Use of Firewall
Server 2
Server 1
Web server
Application
Firewall
Internet
Relay
Relay
SendMail
Database
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Privacy
? Does you system collect personal data? ? Does
the user know that you are collecting personal
data? ? Who is supposed to have access to that
data? Example Dartmouth Medical School ? Who
actually has access to that data? Example
Personnel data files ..... the first subpoena ....
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Requirements, Design and Implementation
Remember the definitions. Example Consistency
between two players of a board game ? The
requirement is ..... ? The design is ..... What
is a requirements specification?
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Final Presentation First Thoughts
? Last week of classes -- 3 or 4 day period ?
Presentation in front of Client(s) Bill
Arms All CS 510 Class is invited Guests ?
Time 45 minutes ? Format -- you select
from Slides Online demonstrations Hand outs
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Final Deliverables
Documentation and programs ? Delivered to
Client and graders ? Due Last day of
classes Project will be graded on ? Client
satisfaction ? Usability ? Maintainability
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Actor and Use Case
? An actor is a user of a system in a
particular role. An actor can be human or
an external system. ? A use case is a a
task that an actor needs to perform with
the help of the system.
BookBorrower
Borrow book
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Use Cases and Actors
? A scenario is an instance of a use case ?
Actor is role, not an individual (e.g.,
librarian can have many roles) ? Actor must be a
"beneficiary" of the use case (e.g., not
librarian who processes book when borrowed) In
UML, the system boundary is the set of use cases.
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Use Cases for Borrowing Books
Borrow copy of book
BookBorrower
Return copy of book
Reserve book
Extend loan
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Relationships Between Use Cases ltltusesgtgt
ltltusesgtgt
Check for reservation
BookBorrower
Borrow copy of book
ltltusesgtgt
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Relationships Between Use Cases ltltextendsgtgt
Refuse loan
ltltextendsgtgt
Borrow copy of book
BookBorrower
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Use Cases in the Development Cycle
? Use cases are a tool in requirements
analysis ? Intuitive -- easy to discuss with
clients ? Use cases are often hard to translate
into class models ? Scenarios are useful to
validate design
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Actions on Objects
returnCopy(c)
call return send create destroy
okToBorrow()
local
status
notifyReturn(b)
asynchronous signal
ltltcreategtgt
stereotypes
ltltdestroygtgt
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Links
LibraryMember borrowCopy() returnCopy()
1
0..
on loan
association
class
message
borrowCopy(c)
cCopy
libMemLibraryMember
link
object
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Sequence Diagram Change in Cornell Program
MEngStudent
Cornellian
1 getName()
1.1 name
2 new PhDStudent(name)
PhDStudent
3 ltltdestroygtgt
sequence numbers added to messages
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Sequence Diagram Borrow copy of a Book
libMem LibraryMember
theBookBook
BookBorrower
theCopyCopy
borrow(theCopy)
okToBorrow
borrow
borrow
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State Diagram
returned()
returned()
not borrowable
borrowable
borrowed()last copy
borrowed()not last copy
State diagram for class Book