2. Course description:
OBJECTIVE:
The understand the Unified Modeling Language and orient towards
Object Oriented methodology using UML for modeling software
systems.
TARGET AUDIENCE:
In particular, it is intended for software professionals who have sound
knowledge of object concepts and some experience towards analysis
and design.
PREREQUISITES:
Good understanding of object concepts.
Sound knowledge of any object oriented language.
Knowledge of software engineering process.
2
3. Course description:
TABLE OF CONTENTS:
Module1 Introduction
Module2 Use case diagram
Module3 Flow of events
Module 4 Realization of the class diagram
Sequence diagram and Collaboration Diagram
Module5 Class diagram and refinement attributes
Module6 State transition and activity diagram
Module7 Implementation diagram
Component diagram and Deployment diagram
Module8 Understanding project culture
Appendix-A
3
5. Importance of modeling
What is a model?
– A model is a simplification of reality
Why do we model?
– help visualizing
– permit specification
– provides a template
– document decisions
5
6. 4 Principles of Modeling
Choose your models well
Every model may be expressed at various
levels of precision
The best models are connected to reality
No single model is sufficient
6
7. What is Software Engineering?
DEFINITION:The application of systematic, disciplined and
qualifiable approach to the development, operation and maintenance
of a software system is software engineering.
Software development life cycle has following stages:
REQUIREMENT
ANALYSIS
DESIGN
IMPLEMENTATION
TESTING 7
8. Effort Distribution for each stage:
Analysis & design 40 %
Development 20 %
Testing 40 %
Analysis - What is to be done ?
Design - How it is to be done ?
Two Popular methodology approaches are:
Structured Analysis & Design
Object Oriented Analysis & Design-OO model
8
9. Major benefits of OOAD:
The object oriented approach is a way of thinking about a problem using
real world concepts instead using adhoc function concepts.
We intent to learn OOAD approach for the following reason:
–Promotes better understanding of user requirements
–Leads cleaner design
–Design flexibility'
–Decomposition of the system is consistent
–Facilitates data abstraction & information hiding
–Software reuse
–Easy maintenance
–Implementation flexibility
9
10. Elements of OO Methodology:
Following are three elements for every OO methodology:
Notation
Process / Method
Tool
10
11. What is Notation?
Notation:
It is collection of graphical symbols for expressing model of the
system.
The Unified Modeling Language [UML] provides a very robust
set
of notation which grows from analysis to design.
This brings end of the method wars as far as notation is concerned
with adoption of the language [UML]
By unifying the notations used by these object oriented methods, the
unified modeling language provides the basis for a de facto standard in
the domain of object oriented analysis and design founded on a wide
11
base of user experience
12. What is UML?
It is a Unified Modeling Language, which is mainly a collection of
graphical notation that methods use to express the designs.
The UML is language for visualizing, specifying, constructing and
documenting the artifacts of software system.
UML is visual modeling language for modeling systems and is non
proprietary
UML is not a radical departure from Booch, OMT, OOSE notations
but rather legitimate successor to all three.
It is an evolutionary step, which is more expressive and more uniform
than individual notations.
Whitehead says
“ By relieving the brain of unnecessary work, a good notation, sets it
free to concentrate on more advance and creative problems “ UML is
not a method or process but is the means to express the same.
12
13. Where can you use the UML?
System of several different kinds, absolutely anywhere everywhere.
Primarily for software intensive systems like:
Systems software
Business processes
13
14. The Evolution of the UML:
OMG vote’97
Public Feedback Submission to OMG, sept’97 UML1.1
Submission of OMG group UML1.0
Beta version OOPSLA’96
UML0.9
Unified Method 0.8
Other method Booch OMT OOSE
14
15. Advantages of UML:
Captures business processes
Enhance communication and ensures the right communication
Capability to capture the logical software architecture independent of
the implementation language
Manages the complexity
Enables reuse of design
15
16. UML refers to:
UML things:
Class, component, node, relationship, package etc..
UML diagrams:
Use case diagram, interaction diagram, class diagram, State
diagram,deployment diagram
16
17. What is Process?
What is Process?
It is an extensive set of guidelines that address the technical and
organizational aspects of software development focusing on
requirements, analysis and design.
Process basically encapsulates the activities leading to the orderly
construction of system model.
OO model supports the iterative and incremental model for the
process.
17
18. More about Process?
Guidance as to the order of team’s activities
It specifies what artifacts should be developed
It directs the task of individual developers and team as a whole
It offers criteria for monitoring and measuring project activities
The selection of particular process will vary greatly depending upon
things like problem domain, implementation technology and skills of
team
Booch,OMT,OOSE and many other methods have well defined
process and UML supports almost all methods
There has been some convergence on development process practices
but there is no consensus for standardization.
Framework for the every stage of software development life cycle.
18
19. Best Practices followed by Rational Unified Process
Develop software iteratively
Manage requirements
Use component based architectures
Visually model software
Verify S/W quality
Control changes to software.
19
20. What is a tool?
It is automated support for every stage of software development
life cycle.
Since we are concentrating on requirement, analysis and design phase,
following are the names of few tools which are greatly in use:
1. Rational Rose
2. Cayenne
3. Platinum
4. Select
20
21. Why Tool?
Helps designer for creating designs much more quickly.
Supports validations like:
Consistency checking
Completeness checking
Constrain checking.
Time required for certain operation could be predicted .
Code generation
Reverse engineering.
Round trip engineering
Conversion from SSAD to OOAD
Quick documentation…etc
21
22. Triangle for Success:
All three components play equally important role towards the success
of the project.
Notation
Tool
Method
22
23. Objective of the first module:
Get introduced with Unified Modeling Language and know the basic
components of software development life cycle.
23
25. OO model:
DYNAMIC MODEL
STATIC MODEL
LOGICAL MODEL
PHYSICAL MODEL
The models of Object Oriented Development
25
26. Models and Views:
4+1 view of OO model.
– Process view
– Deployment view
– Logical view
– Dynamic view
+
– Use case view
As shown in the model , for each dimension we define a number of
diagrams that denote a view of the system’s model.
The use case view is central since its contents drive the developments
of other views.
26
28. Semantics of Diagrams:
· Use case diagrams represent the functions of a system from the user’s
point of view.
· Sequence diagrams are a temporal representation of objects and their
interactions.
· Collaboration diagrams are a spatial representation of objects, links,
and interactions.
· Object diagrams represent objects and their relationships, and
correspond to simplified collaboration diagrams that do not represent
message broadcasts.
· Class diagrams represent the static structure in terms of classes and
relationships.
28
29. Semantics of Diagrams:
Contd...
· State chart diagrams represent the behavior of a class in terms of states
· Activity diagrams are to represent the parallel behavior of an operation
as a set of actions.
· Component diagrams represent the logical components of an
application.
· Deployment diagrams represent the deployment of components on
particular pieces of hardware.
29
30. What is USE CASE diagram?
A use case diagram establish the capability of the system as a whole.
Components of use case diagram:
Actor
Use case
System boundary
Relationship
Actor relationship
Semantic of the components is followed.
30
31. ACTOR:
What is an actor?
An actor is some one or something that must interact with the system
under development
UML notation for actor is stickman, shown below.
Customer Manager Cashier
31
32. ACTOR:
More about an actor:
It is role a user plays with respect to system.
Actors are not part of the system they represent anyone or
anything that must interact with the system.
Actors carry out use cases and a single actor may perform more
than one use cases.
Actors are determined by observing the direct uses of the
system,
32
33. ACTOR:
Contd…
Those are responsible for its use and maintain as well as other systems
that interact with the developed system.
An actor may
- input information to the system.
- receive information from the system.
- input to and out from the system.
33
34. ACTOR:
How do we find the actor?
Ask following questions to find the actors:
– Who uses the system?
– Who installs the system?
– Who Starts up the system?
– What other systems use this system?
– Who gets the information from the system?
– Who provides information to the system?
Actor is always external to the system. They are never part of the
system to be developed.
34
35. ACTOR:
4-Categories of an actor:
Principle : Who uses the main system functions.
Secondary : Who takes care of administration & maintenance.
External h/w : The h/w devices which are part of application
domain and must be used.
Other system: The other system with which the system must
interact.
35
36. ACTOR:
Note:
If newly identified actor is using a system in a same way like an
existing actor, then new actor can be dropped.
If two actors use system in the same way they are same actors.
36
37. USE CASE:
What is USE case?
A use case is a pattern of behavior, the system exhibits
Each use case is a sequence of related transactions performed by an
actor and the system in dialogue.
USE CASE is dialogue between an actor and the system.
Examples:
Open new account Withdrawal of cash
from ATM
37
38. USE CASE:
More about USE CASE:
It is a snapshot of one aspect of system.
They model a dialog between actor and system.
A use case typically represents a major piece of functionality
that is complete from beginning to end.
Most of the use cases are generated in initial phase, but you
find some more as you proceed.
A use case may be small or large. It captures a broad view of a
primary functionality of the system in a manner that can be
easily grasped by non technical user.
38
39. USE CASE:
Contd…
A use case must deliver something of value to an actor.
The use cases may be decomposed into other use cases.
Use cases also present a good vehicle for project planning.
39
40. USE CASE:
How do we find the use cases?
What functions will the actor want from the system?
Does the system store information? What actors will create, read,
update. Or delete that information?
Does the system need to notify an actor about changes in its internal
state?
40
41. USE CASE:
Generic format for documenting the use case:
- Pre condition: If any
– Use case : Name of the case.
– Actors : List of actors(external agents), indicating who
initiates the use case.
– Purpose : Intention of the use case.
– Overview : Description.
– Type : primary / secondary.
– Post condition: If any
Typical Course of Events:
ACTOR ACTION : Numbered actions of the actor.
SYSTEM RESPONSE : Numbered description of system responses.
41
42. USE CASE:
USE CASE documentation example:
The following use case describes the process of opening a new
account in the bank.
Use case :Open new account
Actors :Customer, Cashier, Manager
Purpose :Like to have new saving account.
Description :A customer arrives in the bank to open the new
account. Customer requests for the new account
form, fill the same and submits, along with the
minimal deposit. At the end of complete successful
process customer receives the passbook.
Type :Primary use case.
42
43. Grouping USE CASES:
Those use case functionality which are directly dependent on the
system environment are placed in interface objects
Those functionality dealing with storage and handling of information
are placed in entity objects
Functionality's specific to one or few use cases and not naturally
placed in any of the other objects are placed in control objects
By performing this division we obtain a structure which helps us to
understand the system from logical view
43
44. OOAD --- USE CASE driven
Analysis Design &
Implementation Test
Use cases make up the glue
Implement Verify that use cases
Capture,clarify use cases are satisfied
& validate use cases
44
45. SYSTEM BOUNDARY:
What is System Boundary?
It is shown as a rectangle.
It helps to identify what is external verses internal, and what the
responsibilities of the system are.
The external environment is represented only by actors.
45
46. RELATIONSHIP:
What is Relationship?
Relationship between use case and actor.
Communicates
Relationship between two use cases
Extends
Uses
Notation used to show the relationships:
<< >>
46
47. RELATIONSHIP:
Relationship between use case and actor is often referred as
“communicates” .
Relationship between two use cases is refereed as either uses
or extends.
USES:
- Multiple use cases share a piece of same functionality.
- This functionality is placed in a separate use case rather than
documenting in every use case that needs it.
47
48. RELATIONSHIP:
Contd...
A uses relationship shows behavior that is common to one or
more use cases.
EXTENDS:
It is used to show optional behavior, which is required only
under certain condition.
48
49. USE CASE diagram:
Use case diagram for the shown functionality.
Balance status
report
extends
Withdraw cash
Clerk
Customer
uses
Validation
ATM
Manager
49
50. Objective of the second module
To understand and capture the detailed specification of a system to be
developed, from user perspective.
50
52. Beginning Analysis and Design
Completion of first version of use case diagram initiates the processes
of analysis and design.
UML provides the framework to carry out the process of analysis and
design in form of set of diagrams.
Every diagram and notation used in the diagram carries the semantics.
First step towards analysis and design is to specify the flow of events.
52
53. Flow of Events:
A flow of events document is created for each use case.
Details about what the system must provide to the actor when the use
is executed.
Typical contents
– How the use case starts and ends
– Normal flow of events
– Alternate flow of events
– Exceptional flow of events
Typical Course of Events has:
Actor Action(AA)
System Response(SR)
53
54. Normal Flow of Events:
For withdrawal of cash:
1.(SR) The ATM asks the user to insert a card.
2.(AA) The user inserts a cash card.
3.(SR) The ATM accepts the card and reads its serial number.
4.(SR) The ATM requests the password.
5.(AA) The user enters 1234.
6.(SR) The ATM verifies the serial number and password with the
bank and gets the notification accordingly.
7.(SA)The ATM asks the user to select the kind of transaction.
8.(AA)User selects the withdrawal.
54
55. Normal Flow of Events:
Contd...
9.(SR)The ATM asks for the amount of cash; user enters Rs. 2500/-
10.(SR)The ATM verifies that the amount of cash is within predefined
policy limits and asks the bank, to process the transaction which
eventually confirms success and returns the new account balance.
11.(SR) The ATM dispenses cash and asks the user to take it.
12.(AA) The user takes the cash.
13.(SR) The ATM asks whether the user wants to continue.
14.(AA) The user indicates no.
55
56. Normal Flow of Events:
Contd...
15.(SR) The ATM prints a receipt, ejects the card and asks the user to
take them
16.(AA) The user takes the receipt and the card.
17.(SR) The ATM asks a user to insert a card.
56
57. Alternative Flow of Events:
For withdrawal of cash use case:
9. The ATM asks for the amount of cash; the user has change of mind
and hits the “cancel”.
57
58. Exceptional Flow of Events:
For withdrawal of cash use case:
3 Suspicious pattern of usage on the card.
10 The machine is out of cash.
11 Money gets stuck in the machine.
58
59. Why flow of events?
It helps in understanding the functionality of a system to be developed.
Flow of events helps in finding objects of the system to be developed.
Happens to be most important and very first step towards analysis and
design.
59
60. What is Scenario?
The functionality of the use case is captured in flow of the
events.
A scenarios is one path through the flow of events for the use
case.
Scenarios are developed to help identify objects, classes and
object interactions for that use case.
60
61. Objective of the third module
To understand the flow of each functionality and find out the objects
and methods required to build the system.
61
63. USE CASE Realizations:
The use case diagram presents an outside view of the system
Interaction diagrams describe how use cases are realized as
interactions among societies of objects.
Two types of interaction diagrams
– Sequence diagrams
– Collaboration diagrams
63
64. What is Interaction diagram?
Interaction diagrams are models that describe how groups of objects
collaborate in some behavior
There are 2 kinds of interaction diagrams
• Sequence diagram
• Collaboration diagram
Sequence diagrams are a temporal representation of objects and their
interactions
Collaboration diagrams are spatial representation of objects, links and
interrelations
64
65. What is sequence diagram?
Typically these diagrams capture behaviors of the single
scenario.
Shows object interaction arranged in time sequence.
They show sequence of messages among the objects.
It has two dimensions, vertical represents time & horizontal
represents objects.
Components of sequence diagram:
-objects
-object lifeline
-Message
-pre/post conditions.
65
66. OBJECT & OBJECT LIFE LINE:
Object are represented by rectangles and name of the objects are
underlined.
Object life line are denoted as dashed lines. They are used to
model the existence of objects over time.
Name:Class
66
67. MESSAGES:
They are used to model the content of communication between
objects. They are used to convey information between objects and
enable objects to request services of other objects.
The message instance has a sender, receiver, and possibly other
information according to the characteristics of the request.
Messages are denoted as labeled horizontal arrows between life lines.
The sender will send the message and receiver will receive the
message.
67
68. MESSAGES:
Contd…
May have square brackets containing a guard conditions. This is a
Boolean condition that must be satisfied to enable the message to be
sent.
May have have an asterisk followed by square brackets containing an
iteration specification. This specifies the number of times the message
is sent.
May have return list consisting of a comma -separated list of names
that designate the values of returned by the operation.
Must have a name or identifier string that represents the message.
May have parentheses containing an argument list consisting of a
comma separated list of actual parameters passed to a method.
68
69. Sequence diagram [for withdrawal of cash, normal flow]
:Customer Insert card
:ATM :Bank
Request password
Enter the password
Verify account
Account o.k.
Request option
Enter option Create
Request amount
Transaction
:Transaction
Enter the amount
Update transaction
Transaction commit
Transaction
Dispense cash complete
Request take cash
Take cash
Request continuation
Terminate
Print receipt ,eject card
Request take card
Take card 69
Display main screen and prompt for the card.
70. What is Collaboration diagram?
Collaboration diagrams illustrate the interaction between the objects,
using static spatial structure.
Unlike sequence diagram the time is not explicitly represented in these
diagrams
In collaboration diagram the sequence of messages is indicated by
numbering the messages. The UML uses the decimal numbering
scheme.
In these diagrams, an actor can be displayed in order to represent the
triggering of interaction by an element external to the system.
This helps in representing the interaction, without going into the
details of user interface.
70
71. Components of collaboration diagram:
Named objects
Links: Links are represented by a continuous line between objects, and
indicates the exchange of messages.
Messages has following attributes:
• Synchronization --thread name, step within thread.
• Sequence number
• Message labels : The name of the message often corresponds to an operation
defined in the class of the object that is the destination of the message.
Message names may have the arguments and return values.
• *[iteration].
• It uses decimal notation.
• Message direction.
71
72. Semantics of components:
Object names identify which objects are participating and the links
show which objects collaborate
A link between two objects must exist for one object to send message
to another and vice a versa.
Messages in the collaboration diagram get transformed to more
detailed signature.
They use the decimal notation system for numbering the messages.
The direction of the message defines the sender and receiver of
the message
72
73. The elements of message:
Predecessor
Role names
Message qualifiers
– Iteration expression
– Parameters
– Return values
– Guard
– Message stereotypes
Concurrent thread sequencing
Thread dependencies
Message expression
[Pre] A1:*(expression):doIt(p,r):return value
73
74. The examples of message:
4:Display(x,y) Simple
message
3.3.1:Display(x,y) Nested
message
4.2:subtract[Today,Birthday]:age Nested
message with
return value
[Age >=18] 6.2:Vote() Conditional
message
4.a,b.6/c.1:Turnon(Lamp) Synchro. with
other flow of
execution
1*:wash() Iteration
3.a,3.b/4*||[i:=1..n]:Turnoff() Parallel
iteration
74
75. Collaboration diagram [for withdrawal of cash, normal flow.]
1. Insert card
Enter password, Enter kind
Enter amount,
Take cash, Take card
cancel,Terminate, Continue Create Transaction
Transaction complete
CUST- TRANSA-
OMER Display main screen
unreadable card message,
ATM CTION
request password,
request kind, request amount,
canceled message, eject card, failure message,
dispense cash, request take cash
Transaction succeed
request continuation,
Transaction failed
print receipt, request take card
account o.k.
bad account message, Verify account, bad account,
bad bank account message process transaction bad password,
bad bank code
BANK
75
76. Objective of the fifth module
To know the interaction among the objects in temporal and spatial
form.
To know how objects collaborate among each other and hence
delegate the responsibility to the respective objects.
To understand how the messages get matured with more information.
76
78. What is Class diagram?
A class diagram shows the existence of classes and their relationships
in the logical view of a system
UML modeling elements in class diagrams are:
– Classes, their structure and behavior.
– relationships components among the classes like association,
aggregation, composition, dependency and inheritance
– Multiplicity and navigation indicators
– Role names or labels.
78
79. Major Types of classes:
Concrete classes
A concrete class is a class that is instantiable; that is it can have
different instances.
Only concrete classes may be leaf classes in the inheritance tree.
Abstract classes
An abstract class is a class that has no direct instance but whose
descendants classes have direct instances.
An abstract class can define the protocol for an operation without
supplying a corresponding method we call this as an abstract
operation.
An abstract operation defines the form of operation, for which each
concrete subclass should provide its own implementation.
79
81. ASSOCIATION:
These are the most general type of relationship:
It denotes a semantic connection between two classes
It shows BI directional connection between two classes
It is a weak coupling as associated classes remain somewhat
independent of each other
Example:
CUSTOMER
ATM system
81
82. AGGREGATION:
This is a special type of association
The association with label “contains” or “is part of” is an
aggregation
It represents “has a “ relationship
It is used when one object logically or physically contains other
The container is called as aggregate
It has a diamond at its end
The components of aggregate can be shared with others
It expresses a whole - part relationships
82
84. COMPOSITION:
This is a strong form of aggregation
It expresses the stronger coupling between the classes
The owner is explicitly responsible for creation and deletion of
the part
Any deletion of whole is considered to cascade its part
The aggregate has a filled diamond at its end
Window Client Area
84
85. INHERITANCE:
The inheritance relationship helps in managing the complexity by
ordering objects within trees of classes with increasing levels of
abstraction. Notation used is solid line with arrowhead,shown below.
Generalization and specialization are points of view that are based on
inheritance hierarchies.
Account
CurrentAccount SavingAccount
85
86. DEPENDENCY:
Dependency is semantic connection between dependent and
independent model elements.
This association is unidirectional and is shown with dotted
arrowhead line.
In the following example it shows the dependency relationship
between client and server.
The client avails services provided by server so it should have
semantic knowledge of server.
The server need not know about client.
Client Server
86
87. INSTANTIATION
This relationship is defined between parameterized class and
actual class.
Parameterized class is also referred as generic class.
A parameterized class can’t have instances unless we first
instantiated it
Example:
Element
Queue
Queue<int>
87
88. What is Cardinality? :
Definition: Number of instances of each class involved in the
dialogue is specified by cardinality.
Common multiplicity values:
Symbol Meaning
1 One and only one
0..1 Zero or one
M…N From M to N (natural integer)
0..* From zero to any positive integer
1..* From one to any positive integer
Also thought can be given about navigability to every applicable
relationship.
88
89. Reaching the class diagram:
In collaboration diagram we have shown the objects, their interaction
and detailed message signature.
This information is carried forward to the class diagram.
At this point,we group the similar objects and form classes.
Messages get mapped to responsibilities for respective classes.
Find the attributes for every class.
Transform the links to appropriate relationships.
Relationship is further refined with respect to multiplicity and
navigability.
This complete procedure brings the minimal class diagram [for withdraw cash
use case, normal flow.]
89
90. Class diagram [for withdrawal of cash, normal flow]
Customer
1
1..*
1..*
ATMSystem
0..*
Transaction 1
1
1..* Bank[Branch]
1
90
91. What more to the Class Diagram?
Till this slide we have worked out the essentials of class diagram for
withdrawal of cash use case, normal flow of events.
Similar exercise required to be carried out for every scenario and
clubbed all in the class diagram.
At this point, we refine this integrated class diagram to add further fine
details. Approximate sketch for this class diagram has been shown at
the end of this module.
Refinement attributes should be updated right from sequence diagram
to class diagram.
Next few slides will take into the discussion of refinement attributes.
This process of iterative and incremental development will continue
till there is no change in two consecutive iteration.
91
92. OOAD---Iterative & Incremental Approach
Identify objects
Validate Classes Identify Messages
& Objects
Group Objects
Group classes into classes
into domains
Identify & classify
Identify class Class relationships 92
behavior
93. Refinement attributes:
Stereotypes:
Stereotypes are part of the range of extensibility mechanism provided
by UML
It permits user to add new model element classes on top of the kernel
predefined by UML
93
94. Refinement attributes:
Contd…
Constraints:
Constraints are functional relationship between the entities and object
model. The entities include objects, classes, attributes, association,
links.
A constraint restricts the values that entities can assume.
UML doesn't specify a particular syntax for constraints, other than
they should appear between braces, so they may therefore be
expressed using natural language, pseudo code, navigation expression
or mathematical expression
UML1.2 does prefer the use of a constraint language OCL i.e. Object
Constraint Language, which is subset of UML.
94
95. Refinement attributes:
Example:Constraints
Number of withdrawal transaction should be less than five per day.
Constraint on the same class.
Transaction
{No. of transaction <=5 /day}
No window will have an aspect ratio i.e. (length/width) of less than 0.8 or > 1.5
Window A constraint between the
length/width properties of the same object
{0.8<=length/width <= 1.5}
95
96. Refinement attributes:
Qualifier:
UML provides a role of constraint notation to indicate different kind
of collections that may be inherent in the analysis model
Common role constraints for multi valued roles include
{ordered} Collection is maintained in sorted manner
{bag} Collection may have multiple copies of same item.
{set} Collection may have at most one copy of given item.
Some constraints may be combined such as: {ordered set}
96
97. Refinement attributes:
Qualifier:
Another common design scheme is to use a key value to retrieve an
item from the collection. This is called as qualified association and the
key value as qualifier.
A qualified association is the UML equivalent of a programming
concept variously known as associative arrays, maps,dictionaries
A qualified association relates two object classes and a qualifier
The qualifier is a special attribute that reduced the effective
multiplicity of an association.
One to many and many to many association may be qualified.
97
98. Refinement attributes:
Check for many to many relationship, if any, normalize with qualifier
or association class.
Check for the scope forming abstract classes and template classes.
Check for helper functions.
Thought can be given for using the design patterns.
98
99. Objective of the fifth module:
Learn to build the architecture, which contains the entire information
of the system to be developed.
It is this architecture which is called as BLUE PRINT is handed over
for coding.
99
100. Refined Class diagram [for withdrawal of cash]
Few more relationship can be further added to the shown diagram:
Area ATMSystem BatchJob
1..* Cash
BankComputer
1
Bank[Branch]
<<abstract>>
AccountAccessor
1 1 <<abstract>>
person
Transaction
CashierStation
1..*
1 ATMScreen
Slips Customer BankAssociates
1..*
1
<<abstract>> TellerScreen
Account
1 0..1
BankCard NoteHelpForBankCard
1
CurrentAccount SavingAccount
100
102. What is state transition diagram?
A state transition diagram shows the states of a single object, the
events or the messages that cause a transition from one state to another
and the action that result from a state change.
A state transition diagram will not be created for every class in the
system.
Components of State Diagram:
– Start State
– Stop state
– State Transition
102
103. Semantics of every components:
State: A state is a condition during the life of an object when it
satisfies some condition, performs some action, or waits for an event.
The UML notation for a state is a rectangle with rounded corners.
Special states:There are two special states.
Start state: Each state diagram must have one and only one start
state. Notation for start state is “filled solid circle”.
Stop State: An object can have multiple stop states. Notation for stop
state is bull’s eye.
103
104. Semantics of every components:
Contd...
State transition: A state transition represents a change from an
originating to a successor state.
Transition label: event name[guard condition] / action
104
105. State Transition Diagram [for Account class. ]
request and fill the form for new saving account[ validate ] / process
Open
transaction request[ validate ] / update()
transactionStrart / Transfer_to_main_ledger () Operational
Dormant
no transaction / Transfer_to_Dormant_Ledger
fill_the_request_form/update( Fraud or authorized instruction[Validate]
) / lockAccount()
matter_resolved[ validate ] / unlockAccount()
close
seized
fill_the_request_form / update()
Note:Account can be closed from open state as well
105
106. More about State Diagram:
A state diagram will not be created for every class.
state diagrams are used only for those classes that exhibit interesting
behavior.
State diagrams are also useful to investigate the behavior of user
interface and control classes.
State diagram are used to show dynamics of a individual class
106
107. What is activity diagram?
It is a special kind of state diagram and is worked out at use case level.
These are mainly targeted towards representing internal behavior of a
a use case.
These may be thought as a kind of flowchart.
Flowcharts are normally limited to sequential process; activity
diagrams can handle parallel process.
Activity diagrams are recommended in the following situations:
s Analyzing use case
s Dealing with multithreaded application
t Understanding workflow across many use cases.
107
108. Consistency Checking
Consistency checking is the process of ensuring that,
information in both static view of the system(class diagram)
and the dynamic view of the system(sequence and
collaboration diagram) is telling the same story.
108
109. Objective of the sixth module
Understand the dynamic behavior of a class
Way to find the parallel processes at use case level.
109
111. What is component diagram?
COMPONENT DIAGRAM:
Component diagrams illustrate the organizations and dependencies
among software components.
A component may be
• A source code component
• A run time components
• An executable component
• Dependency relationship.
111
112. Component Diagram [for withdrawal of cash]
policy.dll
Bank
Server.exe
Branch
customer.dll Bank.dll
Branch
Bank.exe
ATM.exe
112
113. What is deployment diagram?
A deployment diagram shows the relationship among software and
hardware components in the delivered system.
These diagram include nodes and connections between nodes.
Each node in deployment diagram represents some kind of
computational unit, in most cases a piece of hardware.
Connection among nodes show the communication path over which
the system will interact.
The connections may represent direct hardware coupling line RS-232
cable, Ethernet connection, they also may represent indirect coupling
such as satellite to ground communication.
113
117. Understanding the project culture
It may be:
1.Calendar Centric
2.Requirement Centric
3.Documentation Centric
4.Quality Centric
5.Architecture Centric
117
118. Understanding the project’s culture
Architecture driven projects represent the most mature style of
development.
These projects are characterized by a focus on creating a frame
work that satisfies all known requirement, yet is resilient enough to
adapt to those requirements, that are not yet known or well
understood.
In every sense of the word, architect-driven policies are in
evolutionary step beyond requirement driven policies.
Architecture driven style of development is usually the best
approach for the creation of most complex software intensive
118
systems
119. Understanding the project’s culture
Architecture driven style of development typically observe the
following process:
1. Specify the system’s desired behavior through a collection of
scenarios. (Analysis)
2. Create, then validate, an architecture. (Design)
3. Evolve that architecture, making mid-course corrections as
necessary to adopt to new requirements as they are uncovered.
119
120. OOAD---Architecture Centric
What exactly is nature of the well structured object oriented
architecture??
1. A set of classes, typically organized into multiple hierarchies.
2. A set of collaboration that specify how those classes co-operate
to provide various system function.
120
121. ESSENCE OF OOAD AND UML
Use case driven
Architecture centric
Incremental and iterative approach.
121
122. Desire for good Architecture
Those of us who have been trained as architects have this desire
perhaps at the very center of our lives,that one day, some where
somehow, we shall build one building which is wonderful, beautiful,
breathtaking, a place where people can walk and dream for
centuries.
CHRISTOPHER ALEXANDER
Same desire should also be applicable in creating software architecture as
well.
122
124. Strong recommendation
Object Technology
– David A. Taylor
Object Oriented Analysis and design with Applications
– Grady Booch
UML distilled
–Martin Fowler
Instant UML
– Pierre - Alain Muller
Software Engineering
– Roger S Pressman
124
125. REFERENCES
Contd...
Object Oriented Modeling and Design
– James Rumbaugh
Object Oriented Software Engineering
– Ivar Jacobson
Clouds to code
– Jesse Liberty
Applying use cases
– Geri Schneider
–Jason p. Winters
UML Toolkit
– Hans-Eriksson and Magnus Penker Version1.1
125
127. Course description:
SESSION BREAKUP:
The course will be offered in series of fourteen hours theory session.
One demonstration session on the tool like Rational Rose can be
accompanied.The following is the suggested agenda for the course.
Session Duration
Module-1,2 2-hours demonstration lecture
Module-3 2-hours
Module-4 2-hours
Module-5 4-hours
Module-6 2-hours
Module-7,8 2-hours
Demonstration 2-hours
127
128. Course description:
REFERENCE AND READING MATERIALS:
Refer to Appendix-A
EXERCISE AND HANDS ON:
One case study should be given to the group of four members.
TEST:
Case study given for exercise can be evaluated as part of the test.
128
129. Course description:
INSTRUCTION TO THE FACULTY:
Course should emphasize on OO modeling.
Focus should be primarily on understanding UML[1.2] and UML
diagrams and then applying to a problem.
Several excellent references are given in Appendix-A. Following are
strongly recommended reading and should be used as supplementary
with this power point courseware.
1.UML toolkit by Eriksson and Magnus Penker
2.Object oriented analysis and design with applications by Grady Booch
Note: UML toolkit should be refereed for UML notations,their syntax and semantics.
Object oriented analysis and design with applications should be refereed for OO concepts.
129
