Advanced class & relationship, Package, Object Diagram

1. T.Y. B.Sc. (Comp. Sci.) Sem I
Object Oriented Software Engineering
(OOSE)
CS-336
Faculty
Dr. Amit D. Kasliwal
Asst. Professor

2. Chapter 4
Advanced Structural Modeling
Overview
 Advanced classes
 Advanced Relationship
 Interface
 Types and Roles
 Packages
 Object Diagram

3. Advanced Classes
In UML, following are the different ways to implement
class as a classifier
A Classifier is a mechanism that describes structural and
behavioral features.
Include classes, associations, interfaces, datatypes, signals,
components, nodes, use cases and subsystems.
A Class is a description of a set of objects that share the
same attributes, operations, relationships, and semantics.

4. Advanced Classes
Interface : collection of operations used to specify a
service of a class or a component.
Datatype : Including primitive built-in types as well as
enumeration types (such as Boolean). Also immutable.
Association : A description of a set of links, each of which
relates two or more objects.
Signal : The specification of an asynchronous message
communicated between instances.

5. Advanced Classes
Component : A modular part of a system that hides its
implementation behind a set of external interfaces.
Node : a physical element that exists at run time and
that represents a computational resource, generally having
at least some memory and often processing capability.
Use case : A description of a set of a sequence of actions,
including variants, that a system performs that yields an
observable result of value to a particular actor.
Subsystem A component that represents a major part of a
system.

6. Advanced Classes

7. Advanced Classes
With the advanced classes, we can specify visibility for an
attribute or operation in any of four levels.
Public : Any outside classifier with visibility to the given
classifier can use the feature, specified by the symbol +.
Protected : Any descendant of the classifier can use the
feature; specified by prepending the symbol #.
Private : Only the classifier itself can use the feature;
specified by prepending the symbol -.
Package : Only classifiers declared in the same package
can use the feature; specified by prepending the ~.

8. Advanced Classes

9. Interfaces
 Collection of operations used to specify a service.
 Specify a behavior of an a element (class or component)
independent of its implementation.
 Important for large scale project where different teams
are developing different parts of the system
 Described by abstract operations (signatures)
 Used to model the seams (flow) of a system
 Components on each side of seams should not be
affected by changes on the other side

10. Interfaces
 Graphical Representation:
Or Class Stereotype: <<interface>>
Storable
load()
save() no attribute

11. Interfaces Relationships
 Participate in: generalization, association dependency,
realization
 Realization: Class or Component may realize one (or
many) interface(s):
 class provides a set of methods that implement the
operations of all the interfaces it realizes
 Exemple:
SensorTelemetry
Filter
realization
dependency

12. Types and Roles
 Types:
 Same as Interface + Attributes
 Allow to model the semantics of an abstraction and its
conformance to a specific interface.
 Roles:
 In a given context, an instance may present only one of
its interface. Each interface represents a role the object
plays
Person Companye:Employee

13. Packages
 General purpose mechanism for organizing modeling
elements into groups
 Use Packages for Architecture Views
 Organize elements semantically close into large chunks
 Well structured Packages are loosely coupled and very
cohesive
 Graphical Representation:
Shape

14. Packages
 Package may own other elements
 classes, interfaces, components, nodes, collaborations,
use cases, other packages.
 Package form namespace (same named element cannot be
in same package, but can be in two different packages)
Shape
Shape
+ height
+ length
- radius
Square
Circle
Triangle

15. Packages Visibility
 Specify whether an element owned by a package can be
used by other package:
 + public: any package that import this package can use
the feature
 # protected: any descendant of the package can use the
feature
 - private: only the elements in the package itself can
use the feature
 Collectively the public parts of a package constitute the
package’s interface

16. Package Example
GUI
Bus.Obj.
DB
AppWin AppFrame Facade to
Relational
Translation
SQL
Generator
Facade
Service
Control
Business
Object
Entity
Business
Object

17. Object Diagram
• It is a concrete manifestation of an abstraction to which a
set of operations can be applied and which has a state
that stores the effects of the operations
• an object in object diagram is rendered by underlining
its name in the class symbol

18. Object Diagram
• An object has state and therefore it is dynamic.
• When we visualize its state, we are really specifying the
value of its state at a given moment in time and space.
• When we operate on object, we typically change its state;
when you query an object, you don't change its state

19. Object Diagram
• Model the instances of things contained in class diagrams.
• Shows a set of objects & their relationships at a point in time.
• Use to model the static design view or static process view of a
system.
• It is not only important for visualizing, specifying, and
documenting structural models, but also for constructing the
static aspects of systems.
• An object diagram covers a set of instances of the things
found in a class diagram.

20. Object Diagram

21. Object Diagram
• Commonly contain Objects and Links. Also may contain notes
and constraints.
• We say, If class A has a one-to-many association to class B,
then for one instance of A there might be five instances of B;
for another instance of A there might be only one instance of
B.
• To model an object diagram,
• identify the mechanism you'd like to model that should
represents some function or behavior of the part of the
system you are modeling that results from the interaction
of a society of classes, interfaces, and other things
• Then create a collaboration to describe a mechanism.

22. Object Diagram
• To model an object diagram,
• identify the mechanism you'd like to model that should
represents some function or behavior of the part of the
system you are modeling that results from the interaction
of a society of classes, interfaces, and other things
• Then create a collaboration to describe a mechanism.
• For each mechanism, identify the classes, interfaces, and
other elements that participate in this collaboration;
identify the relationships among these things as well.
• Expose the state and attribute values of each such object, as
necessary, to understand the scenario.
• Similarly, expose the links among these objects,
representing instances of associations among them.

23. Object Diagram : Example