PEMODELAN PERANGKAT LUNAK Sequence Diagram Slide 2 Merupakan
suatu diagram interaksi yang memodelkan suatu skenario tunggal yang
dijalankan pada sistem Digunakan untuk memperlihatkan interaksi
antar obyek dalam perintah yang berurut. Tujuan utama adalah
mendefinisikan urutan kejadian yang dapat menghasilkan output yang
diinginkan Slide 3 Sequence Diagram Partisipan : obyek atau entitas
yang bertindak dalam sequence diagram Message : komunikasi antar
obyek partisipan Terdapat 2 tipe garis yaitu vertikal dan
horisontal Vertikal : waktu maju berdasarkan waktu Horisontal :
obyek mana yang beraksi Slide 4 Elemen Notasi Didefinisikan pada
UML 2.0 Digambarkan dalam bentuk frame Bersifat optional untuk
menggambarkan batas grafis suatu diagram. Slide 5 Elemen Notasi
(cont.) A sequence diagram that has incoming and outgoing messages
Slide 6 Elemen Notasi (Labeling) The UML specification provides
specific text values for diagram types sd = Sequence Diagram,
activity = Activity Diagram, use case = Use Case Diagram
DiagramType DiagramName Slide 7 Types of Interaction Creation
Menunjukkan pesan yang menyebabkan terjadinya pembentukan instan
obyek. Synchronous Pesan yang dikirim oleh 1 obyek ke obyek lain
dan obyek pertama menunggu sampai hasil aksi selesai. Asynchronous
Pesan yang dikirim oleh 1 obyek ke obyek lain dan obyek pertama
tidak menunggu sampai hasil aksi selesai. Reply Menunjukkan nilai
kembali dari obyek ke obyek yang megirim pesan Sumber : schaum
outline Slide 8 Guidelines for Building a UML Sequence Diagram 1.
Set the context (i.e. scope the system) 2. Identify participating
objects 3. Draw arbitrary lifelines for each class 4. Draw the
duration of the objects on the class lifeline 5. Insert the object
messages from top to bottom of diagram (time-based) 6. Check the
diagram for completeness Slide 9 Lifelines Elemen notasi lifeline
terletak pada posisi atas diagram Represent either roles or object
instances that participate in the sequence being modeled Standar
penamaan lifeline : Instance Name : Class Name Slide 10 Messages
The first message of a sequence diagram always starts at the top
and is typically located on the left side of the diagram for
readability. Subsequent messages are then added to the diagram
slightly lower then the previous message. Slide 11 Message (cont.)
the analyst object makes a call to the system object which is an
instance of the ReportingSystem class. The analyst object is
calling the system object's getAvailableReports method. The system
object then calls the getSecurityClearance method with the argument
of userId on the secSystem object, which is of the class type
SecuritySystem the secSystem object returns userClearance to the
system object when the getSecurityClearance method is called. The
system object returns availableReports when the getAvailableReports
method is called. Slide 12 Message (cont.) the system object
calling its determineAvailableReports method. Slide 13 Message
(cont.) Asynchronous Messages : digunakan pada proses konkurensi
Slide 14 Guards When modeling object interactions, there will be
times when a condition must be met for a message to be sent to the
object. the guard is the text "[pastDueBalance = 0]." By having the
guard on this message, the addStudent message will only be sent if
the accounts receivable system returns a past due balance of zero
Slide 15 Combined fragments (alternatives, options, and loops) A
combined fragment is used to group sets of messages together to
show conditional flow in a sequence diagram. The UML 2
specification identifies 11 interaction types for combined
fragments. Slide 16 Alternatives Alternatives are used to designate
a mutually exclusive choice between two or more message sequences.
Alternatives allow the modeling of the classic "if then else" logic
e.g. if I buy three items, then I get 20% off my purchase; else I
get 10% off my purchase. Slide 17 Alternatives (cont.) Slide 18
Option The option combination fragment is used to model a sequence
that, given a certain condition, will occur; otherwise, the
sequence does not occur. An option is used to model a simple "if
then" statement (i.e., if there are fewer than five donuts on the
shelf, then make two dozen more donuts). Slide 19 Option (Cont.) if
a student's past due balance equals zero, then the addStudent,
getCostOfClass, and chargeForClass messages are sent. If the
student's past due balance does not equal zero, then the sequence
skips sending any of the messages in the option combination
fragment. Slide 20 Loops Occasionally you will need to model a
repetitive sequence. In UML 2, modeling a repeating sequence has
been improved with the addition of the loop combination fragment.
Slide 21 Loops (cont.) Slide 22 Referencing another sequence
diagram Starting in UML 2, the "Interaction Occurrence" element was
introduced. Interaction occurrences add the ability to compose
primitive sequence diagrams into complex sequence diagrams. The
text "ref" is placed inside the frame's namebox, and the name of
the sequence diagram being referenced is placed inside the frame's
content area along with any parameters to the sequence diagram.
Slide 23 Interaction Occurrence Slide 24 Interaction Occurrence
(cont.) Slide 25 Gates Gates can be an easy way to model the
passing of information between a sequence diagram and its context.
A gate is merely a message that is illustrated with one end
connected to the sequence diagram's frame's edge and the other end
connected to a lifeline Slide 26 Gates (cont.) Slide 27 Slide 28
Break almost identical in every way to the option combined
fragment, with two exceptions. a break's frame has a namebox with
the text "break" instead of "option." when a break combined
fragment's message is to be executed, the enclosing interaction's
remainder messages will not be executed because the sequence breaks
out of the enclosing interaction break combined fragment is much
like the break keyword in a programming language like C++ or Java
Breaks are most commonly used to model exception handling Slide 29
Slide 30 Parallel When the processing time required to complete
portions of a complex task is longer than desired, some systems
handle parts of the processing in parallel The parallel combination
fragment is drawn using a frame, and you place the text "par" in
the frame's namebox break up the frame's content section into
horizontal operands separated by a dashed line. Each operand in the
frame represents a thread of execution done in parallel. Slide 31
Parallel (cont.) A microwave is an example of an object that does
two tasks in parallel Slide 32 Summary The sequence diagram is a
good diagram to use to document a system's requirements and to
flush out a system's design. The reason the sequence diagram is so
useful is because it shows the interaction logic between the
objects in the system in the time order that the interactions take
place. Slide 33 References UML 2.0 Superstructure Final Adopted
Specification UML 2 Sequence Diagram Overview UML 2 Tutorial Slide
34 Try this yourself Draw up a sequence diagram modelling the case
when an advert campaign manager retrieves the details of a
particular clients advertising campaign and lists the details of a
particular advert from the campaign. The sequence diagram should
also show the case when a new advert is created. Only call messages
(synchronous) should be used in this example and use any iteration
conditions as you deem necessary. Objects to use: CampainManager,
Client, Campaign, and Advert Slide 35 A Solution to Previous Slide
Slide 36 Try this too Create a sequence diagram modelling the
behaviour of a PCB drilling machine. The machine will drill holes
in a PCB of given dimensions at a set of given co-ordinates.
Co-ordinates are given as a list, which must contain at least one
set of co- ordinates. Drilling stops when the end of the list is
reached or when a user interrupts the process. Slide 37 A Solution
to Previous Slide Slide 38 Question
