Compilation of diagrams I found here.. Sequence Diagrams State Transition Diagrams Activity Diagrams Credits to the owner

1. Sequence
Diagram
Systems Analysis and Design

2. Introduction to Sequence
diagram
Sequence diagram is interaction diagram that shows the set of
objects and messages send and receive by those object.
It mainly emphases on time ordering and messages.
It is used to illustrate the dynamic view of system.
These are also called as “Isomorphic diagram”.

3. Terms and Concepts
Objects or Participants :-
 The sequence diagram is made up of collection of participants or
objects. Participants are system parts that interact each other during
sequence diagram.
 The participants interact with each other by sending and receiving
message
 The object is represented by as below:
Object:Class_Name

4. Terms and Concepts
Lifeline:-
 Lifeline represents the existence of an object over a period of
time.
 It is represented by vertical dashed line.
 Most objects that appeared in ‘Interaction diagram’ will be in
existence for the duration of an interaction. So, these objects
are aligned at top at top of diagram with their lifeline from top
to bottom of diagram.

5. Terms and Concepts
Activation bar:-
 It is also called as focus of control. It shows the period of time
during which an object is performing an action.
 The top of rectangle is aligned with start of the action. The bottom is
aligned with its completion and can be marked by a written
message
 It is represented by tall thin rectangle:

6. Terms and Concepts
Messages:-
 The interaction in a sequence diagram between the objects can be
shown by using messages.
 The messages on sequence diagram are specifies using an arrow
from participant that wants to pass the messages to the participant
that receive the messages .
 Messages can be flow in whatever direction required for interaction
from left to right and right to left.

7. Terms and Concepts
Messages:-
 It has following kinds of messages:
1)Synchronous messages:-
* It is a message where the sender is blocked and waits until
the receiver has finished processing of message.
* It is invoked the caller waits for the receiver to return from
the message invocation.
* It is represented by solid line with full arrow.
2)Asynchronous messages:-
* It is a messages where the sender is not blocked and can continue executing.
* It is represent by solid line with half arrow.

8. Terms and Concepts
Messages:-
 It has following kinds of messages:
3)Reflexive messages:-
* If the object sends the message to itself then it is called as ‘Reflexive message.
* It is represented by solid line with loops the lifeline of object.
4)Return messages:-
* It can be used at the end of activation bar to show that control flow of activation
returns to the participant that pass the original message.
* It is represent by dashed line from sender to receiver.

9. Terms and Concepts
 It has following kinds of messages:
5)Create messages:-
* It is used to create object during interaction.
* The object can be created by using <<create>> to indicate the timing of creation.
* Creating message can be shown as below:
6)Destroy messages:-
* It is used to destroy the objects during interaction.
* The objects can be terminated using <<destroy>> which points to an “x”.
* It indicates that object named message is terminated.

10. Terms and Concepts
Time:-
 The sequence diagram describes the order in which interaction takes place.
 So time in an important factor. The time on sequence diagram starts at top of the
page just below the object and then progress down the page.
 Time is all about ordering but not duration.

11. Terms and Concepts
Event:-
 It can be referred as smallest part of an interaction and event can occur of at any given
point in a Time.
 When interaction take place, Events are called as build in blocks for messages and signals.
 Event is created while sending and receiving message.

12. Sequence diagram of Railway
reservation system

13. State
Transition
Diagrams
Systems Analysis and Design

14. State Transition Diagrams
• State diagrams describe the life of an object using three main
elements:
• States of an object
• Transitions between states
• Events that trigger the transitions
• A state diagram specifies a state machine
• A state machine is described for a class
• Each object has it’s own state machine

15. States
• State
• is a condition or situation during the life of an object within which it performs
some activity, or waits for some events
• Has a name
• Has actions -- execute the state
• Has internal transitions -- transitions cause no change in a state
• substates -- the nested structure of a state involving disjoint or concurrent
substates

16. States
• For example:
entry/unlock door
do/prepare materials
telephone rings/answer telephone
include/lecture state
exit/lock door
At Work state name
action performed on entry to state
activity performed while in state
action performed on arrival of named event
name of a sub-state machine
action performed on leaving state

17. Initial and Final States
• The initial state of a state machine is indicated with a solid circle
• Known as a pseudo-state
• A transition from this state will show the first real state
• The final state of a state machine is shown as concentric circles
• A closed loop state machine does not have a final state; the object lives until
the entire system terminates
• An open loop state machine represents an object that may terminate before
the system terminates

18. Initial and Final States
• An example:
At Work At Homego home
go to work
die die

19. Actions and Activities
• Action
• is an executable atomic computation
• includes operation calls, the creation or destruction of another object, or the
sending of a signal to an object
• associated with transitions and during which an action is not interruptible --
e.g., entry, exit
• Activity is associated with states
• Non-atomic or ongoing computation
• May run to completion or continue indefinitely
• Will be terminated by an event that causes a transition from the state in which
the activity is defined

20. Events
• An event signature is described as
Event-name (comma-separated-parameter-list)
• Events appear in the internal transition compartment of a state or
on a transition between states
• An event may be one of four types
• Signal event
• Corresponding to the arrival of an asynchronous message or signal
• Call event
• Corresponding to the arrival of a procedural call to an operation
• Time event
• Change event

21. Events
• A time event occurs after a specified time has elapsed
• Event name is specified as keyword after
• Parameter list is an expression evaluating to a time interval
• after(10 seconds after state “At Work” is entered)
• No specified start time implies “since entry to the current state”
• after(2 seconds)

22. Events
• A change event occurs whenever a specified condition is met
• Event name is specified as keyword when
• Parameter list is a boolean expression
• The event occurs when both of the following conditions are met, irrespective of
the order when they happen
• The expression evaluates to true
• The object is in the required state
• For example
• when (state = At Work)
• when (date = January 1 2007)

23. Transitions
A transition is drawn as an arrow between states annotated with a transition
string
• The transition string denotes the event and consequent action
• Only one form of arrowhead is used on statecharts
• The distinction between call events and signal events must be deducted from elsewhere e.g.
an interaction diagram
A transition string is described as
• Event-signature [guard-condition]/action-expression^object.message
• If the guard condition is met the transition occurs immediately

24. Transitions
• A transition is triggered when its event occurs
• If the guard condition is met, the transition is fired
• If the condition is not met the event is discarded
• The guard condition is checked only once
• If there is no guard condition, triggering will always cause firing
• Note the distinction between a guard condition and a change event
• A guard condition is evaluated once, when the associated event occurs
• A change event occurs whenever its associated condition is met
• Behaviour is as if the condition were being continually evaluated

25. State Diagrams notation
PaidUnpaid
paying
Invoice
created
Invoice
destroyed
name
state
final stateInitial state
transition
event

26. State Diagram Example
on loan
entry / myBkCpy.borrow()
on the shelf
entry / myBkCpy.return()
borrow()
return()
on loan
exit / myBkCpy.returned()
on the shelf
exit / myBkCpy.borrowed()
borrow()
return()
Entry action : any action that is marked as linked to the entry action is
executed whenever the given state is entered via a transition
Exit action : any action that is marked as linked to the exit action is
executed whenever the state is left via a transition
This shows the state of an object myBkCpy from a BookCopy class

27. A Class of BookCopy
BookCopy
onShelf : Boolean value := ‘Y’ on the shelf
value := ‘N’ on loan
return()
borrow()
action / onShelf=‘Y’
action / onShelf=‘N’

28. State Diagram - Nested States
Super-state
A B
event-1
C
event-2
A B
C
event-1
event-2event-2

29. Checking
do / check
Item
Dispatching
do / initiate
delivery
Delivering
[all items checked &&
some items not in stock]
Order item
[all items checked && all items available]
Dispatch items
delivery
get first item
Cancelingcancelled
Ordering
Exit/ Item received
do / order Item
*[all items checked]
get next item
entry / deliver
Items
do / Remove
Item
State Diagram Example including substates

30. Concurrent State models
 Orthogonal Components and Concurrency
 shown separated by dashed line
 supports concurrency
 Objects must be in only one state from each of the
orthogonal components
Starting
A
Finishing
B
C
E
F
D G
Explicit control
branching(fork)
s
T

31. Concurrent State Models
Three different ways for orthogonal components to communicate:
• Broadcast Events
• Propogated Events
• IN operators

32. Concurrent State Models
• Broadcast events
• events that more than one orthogonal component accepts
• For example an event T1 is sent to all active orthogonal components it need
not be acted on by all components
• what happens if component S1 is in state A, S2 is in state E and S3 is in state G
when a T1 event occurs?
• what happens if S1 is in state A and S2 is in state D when the event T1 occurs?

33. Concurrent State Models
• Propagated events are indicated with the caret following the event
name (and optional parameters and guard)
• IN operators are used as a guard on transition T4. This allows the
S3 component to take the transition T4 only if S2 is currently in
state D

34. Concurrent State Models
A
B
C
E
F
D
G
S1
T3(a,b,c)
H
H
T1
T2^T3(x,y,z)
H
T1
S2
T4[IN(D)]
T3(a,b,c)
S3
T5
T6
S

35. Activity
Diagrams
Systems Analysis and Design

36. Modeling Process
Phase Actions Outcome
Initiation Raising a business need Business documents
Requirements
Interviewing stakeholders, exploring the system
environment
Organized
documentation
Specification
Analyze the engineering aspect of the system,
building system concepts
Formal specification
Design
Define architecture, components, data types,
algorithms
Formal Specification
Implementation
Program, build, unit-testing, integrate,
documentation
Testable system
Testing & Integration
Integrate all components, verification, validation,
installation, guidance
Testing results,
Working sys
Maintenance Bug fixes, modifications, adaptation System versions

37. Behavior Modeling
Checkout
Manager
Order
message: change
status
Add to cart
Check
availability
Supply
Order
Notify
User
[okay][problem]
Sequence Diagrams Activity Diagrams
Inventory
message: create In process
supplied
Order
State Diagrams

38. Strengths
• Best for modeling complex behavior
• Which does not rely on interactions.
• Has parallel behavior.
• Examples:
• Business workflow (authorizing a loan).
• User behavior (login/logout).
• Algorithms.

39. Activity Diagram for Customer Service
Start
Fork
decision
merge
Join Final Node
Action

40. Tokens
Each fork node generates
tokens, according to the
number of paths.
The initial node creates a
single token
Each join “collects” all the
incoming tokens, producing a
token afterwards.
An action requires a token to
execute, and produce a token
when it ends

41. Object Flows
• Objects describe the interface between actions
Call DataReceive Call Log Call
Receive Call Log Call
Object
Flow
Pins
Call data
Call data
Initiate Call
Call data

42. Objects with States
Object nodes allow state change modeling.
Call Data
[created]
Receive Call
Find Customer
Type
Call Data
[classified]

43. Data Store
• A datastore is a stereotype for an object which stores objects
persistently.
All entering
tokens are
copied so that
tokens never
leave the data
store
If a token is already
present in the data
store, it replaces the old
one

44. Catching Signals
Time Signal Event Signal
Flows when the
time expression is
true
Flows when an
event occurs Sends an event
when a flow
enters

45. Example: Volvo Blind Spot Info System (BLIS)

46. Camera Behavior
Check Objects
in Camera
Is object
Detected?[no]
Side Object
Detected
[yes]
Safety Controller Behavior
Side Object
Detected
Detection data
Alarm Deciding
Side?
Left Alarm Right Alarm
[left] [right]

47. Final Nodes
the activity is terminated when the first
token arrives
the activity is terminated when all
tokens in the graph are destroyed

48. • An action can be decomposed into an subactivity.
• The invoked activity graph can be used by many subactivity states.
Decomposition
Input
Parameter Final Action

49. Partitions
• Partitions (swimlanes) can group actions by:
• class, business unit, person etc…
• Can be multidimensional (not always possible).
Register
Bug
Evaluate
Impact
Fix
Bug
Revise
Plan
Release
Fix
Test
Fix
[ priority = 1]
Management
Support
Engineering

50. Pre / Post Conditions
for Decompositions
for Actions

51. Exceptions
• Exception represent errors and unexpected situations
interruptible
region
Exception
Edge
What happens to
the tokens?
Exception
Handler

52. Multiple events
Actions can throw
events too
Exception info can
be modeled
Multiple event
handlers