1. UML Notations in CommonKADS Activity diagrams State diagrams Class diagrams Use-case diagrams

2. @ Universiteit van Amsterdam UML notations2 Background UML n Nineties: number of popular object-oriented methods n Unified Modeling Language: proposal for set of standard notations n wide attention ä see www.rational.com n mainly meant for analysis phase

3. @ Universiteit van Amsterdam UML notations3 UML notations used n Class diagram ä static information structure (“data”) n Activity diagram ä combined function/control view n Use-case diagram ä high level view of system services (functional) n State diagram ä highly interactive control

4. @ Universiteit van Amsterdam UML notations4 Activity diagram n Model control and information flow of a procedure or process n Useful if control is mainly synchronous ä otherwise: use state diagram n Use in CommonKADS: modeling the organizational process ä worksheet OM-2 of the organization model n Can also be used to model control flow within a task method (knowledge model)

5. @ Universiteit van Amsterdam UML notations5 Action state n State in which some work is being done ä activity, task n State terminates when the work is finished ä difference with state diagrams n After termination the action state can lead to another action state ä “state transition” n Special symbols for being and end of a procedure or process

6. @ Universiteit van Amsterdam UML notations6 Basic notation for activity diagram

7. @ Universiteit van Amsterdam UML notations7 Decision n Sate transition is deterministic n If transition depends on outcome of the work, then introduce a decision

8. @ Universiteit van Amsterdam UML notations8 Introducing concurrency

9. @ Universiteit van Amsterdam UML notations9 Swim lanes n Process can sometimes be distributed over several agents or organizational units n Notation: use compartments n In particular useful when modeling a business process (e.g. in organization model)

10. @ Universiteit van Amsterdam UML notations10 Notation for swim lanes

11. @ Universiteit van Amsterdam UML notations11 Object flow

12. @ Universiteit van Amsterdam UML notations12 Signals

13. @ Universiteit van Amsterdam UML notations13 Business process “Housing”

14. @ Universiteit van Amsterdam UML notations14 Activity diagram of method control

15. @ Universiteit van Amsterdam UML notations15 State diagrams n Synonyms: “state chart”, “state-transition diagram” n Purpose: model of dynamic behavior n Use if control is heavily influenced by “external” events n Draw a state diagram for object classes with interesting behavior n Activity diagram is alternative ä internal control ä object flow

16. @ Universiteit van Amsterdam UML notations16 State

17. @ Universiteit van Amsterdam UML notations17 State transition n Event: comes from outside the object modeled n Message: generates event for another object n Guard: outcome of internal object computation

18. @ Universiteit van Amsterdam UML notations18 Actions and activities n Action: instantaneous, not interruptible ä on transition ä on state entry = action on all incoming transitions ä on state exit = action on all outgoing transitions ä on event n Activity: takes time, interruptible

19. @ Universiteit van Amsterdam UML notations19 State diagram of ticket machine

20. @ Universiteit van Amsterdam UML notations20 State concurrency

21. @ Universiteit van Amsterdam UML notations21 State generalization n If Object A is in super-state S, then the object us in precisely one of the sub-states n Cf. concurrency: “and”-states

22. @ Universiteit van Amsterdam UML notations22 State diagrams in CommonKADS n Communication modeling (Ch. 8) n Asynchronous reasoning control ä real-time applications n Control specification for the business process n Overlap with activity diagrams ä state with no outgoing events = action state

23. @ Universiteit van Amsterdam UML notations23 State diagram “Housing”

24. @ Universiteit van Amsterdam UML notations24 Class diagram n Captures static information structure ä In O-O: also functions n Generalization, inheritance & reuse are important issues n Imported into CommonKADS domain- schema notation ä no use made of operation box n Can also be used in Task Model to sketch task information structure

25. @ Universiteit van Amsterdam UML notations25 Objects and classes

26. @ Universiteit van Amsterdam UML notations26 Object class n Describes a group of objects with similar properties ä Abbreviation: "class" n Rationale for introducing classes: ä it provides a means for abstraction n Terminology: “object” is often used in an ambiguous way, pointing to both objects (in the strict sense) and object classes.

27. @ Universiteit van Amsterdam UML notations27 Attributes n An attribute describes a value held by objects belonging to the class. n Attribute specification consists of: ä Class it is defined on (student) ä Attribute name (name) ä Admissible values (string) ä Optional: default value

28. @ Universiteit van Amsterdam UML notations28 Object and Value n Most O-O approaches distinguish between objects and values. n Difference: a value does not have an identity ä it "lives” only in connection to a certain object. n RULE 1: an object is not allowed as a possible value of an attribute! n RULE 2: attribute names need only to be unique within a class.

29. @ Universiteit van Amsterdam UML notations29 Values and Value Sets n Values are the primitive things with no internal structure from the viewpoint of the application n Admissible values are defined through a value set n Typical predefined value-sets: ä string, number, integer, real, range, boolean, …. n User-defined: ä set or list of strings

30. @ Universiteit van Amsterdam UML notations30 Object Identifiers n In O-O modeling you assume that every object has an identity. n Consequence: introduce only attributes that act as identifiers, iff the identifier is something that exists in the real world. n Examples: student card number, social security number.

31. @ Universiteit van Amsterdam UML notations31 Operations n Definition: ä operation is "a function or a transformation that can be applied to objects of a class". n Objects in a class share the same operations. n Method: implementation of an operation n = functional view

32. @ Universiteit van Amsterdam UML notations32 Class notation

33. @ Universiteit van Amsterdam UML notations33 Associations n Associations are used to link objects to other objects n Majority of associations: ä binary (between two objects) ä directional (should be read in a particular direction n Ternary associations come up occasionally. n Associations between more than three objects are rare.

34. @ Universiteit van Amsterdam UML notations34 Association notation

35. @ Universiteit van Amsterdam UML notations35 Multiplicity examples

36. @ Universiteit van Amsterdam UML notations36 Multiplicity n Also called: "cardinality". n Always connected to one of the classes involved. n Typical types of multiplicity: ä 0-1Zero or one (optional). ä 1Precisely one. ä 0+ Zero or more, ä 1+One or more.

37. @ Universiteit van Amsterdam UML notations37 Association class n Modeling an association as a class if the association has an internal information structure n Advantage: associations become first-class objects. n Attributes and methods can be defined for the association class.

38. @ Universiteit van Amsterdam UML notations38 Notation association class

39. @ Universiteit van Amsterdam UML notations39 Use of an association class

40. @ Universiteit van Amsterdam UML notations40 Associations with specific semantics n Associations provide a general, "neutral", way of connecting object classes. n Semantics of the association are defined through argument typing, multiplicity and (implicitly) the name of the association. n Class diagrams provide specific types of associations, with predefined semantics: ä generalization ("is a"). ä aggregation ("part of").

41. @ Universiteit van Amsterdam UML notations41 Generalization n Purpose: sharing similarities while preserving differences n Is an association between a class that acts as super- class and one or more classes called the sub- classes. n Super-classes show the features that the sub-classes have in common. n Each sub-class inherits the attributes and operations defined on its super-class(es).

42. @ Universiteit van Amsterdam UML notations42 Notation for generalization

43. @ Universiteit van Amsterdam UML notations43 Aggregation n Aggregation denotes a binary association in which one side is an "assembly" and the other side a "part". n "Assembly" and "part" act as predefined roles involved in the aggregation association. n Cardinality of a part can be defined ä precisely one; optional (0-1); many,...

44. @ Universiteit van Amsterdam UML notations44 Notation for aggregation

45. @ Universiteit van Amsterdam UML notations45 Composition n Sub-type of aggregation n Existence of part depends on aggregate

46. @ Universiteit van Amsterdam UML notations46 Aggregation and generalization n Similarities: ä Tree-like structure ä Transitive properties n Differences: ä AND-tree (aggregation) vs. OR-tree (generalization) ä instance tree (aggregation) vs. class tree (generalization)

47. @ Universiteit van Amsterdam UML notations47 Combined aggregation and generalization

48. @ Universiteit van Amsterdam UML notations48 Use-case diagram n shows services that can be expected from a system n provides outsider view (customer) n terminology use caseservice provided by system actoragent using a system service n used in early phases of system analysis n use in CommonKADS: way to present possible solutions to customer

49. @ Universiteit van Amsterdam UML notations49 Use cases for a library

50. @ Universiteit van Amsterdam UML notations50 A small case study n Course administration system (CAS) n Context: university department n Required services: STUDENT: update personal data, inspect exam results, inspect course info, enroll in course TUTOR: inspect exam results, update course info, inspect enrollments ADMIN STAFF: enter exam results, inspect exam results, update personal data students, inspect enrollments

51. @ Universiteit van Amsterdam UML notations51 Use cases

52. @ Universiteit van Amsterdam UML notations52 Class diagram student student-card#: string name: string address: string date-of-birth: data major: Major......... course course-code: string year: integer trimester: 1-3 study-points: integer learning-goals: string description: text literature: text maximum-#students: integer exam date: date result: [0..10] enrollment date: date university staff member title: string position: string department: string telephone: string room: string e-mail: string 0+ course-exam 1 0+ tutor 0+ 1+ 0+ requires

53. @ Universiteit van Amsterdam UML notations53 Activity diagram for course enrollment procedure

54. @ Universiteit van Amsterdam UML notations54 State diagram: “update student data”