This document provides an overview of the Unified Modeling Language (UML) for object-oriented data modeling. It describes UML as a complete language for capturing and communicating knowledge about a subject. The document outlines the goals of UML, the advantages it provides, and how it can be used. It also describes the different categories of UML diagrams including structural diagrams for describing static relationships and behavioral diagrams for describing dynamic relationships. Use case models and how they represent user interactions with a system are discussed. An example use case diagram for an order placement process is included.

1. Chapter – 5
Object-Oriented DM using UML
PART - 1

2. Unified Modeling Language (UML)
• UML is a language.
• It is not simply a notation for drawing diagrams, but a
complete language for capturing knowledge (semantics)
about a subject and expressing knowledge (syntax)
regarding the subject for the purpose of communication.
•

3. • Applies to modeling and systems.
• Modeling involves a focus on understanding a subject
(system) and capturing and being able to communicate in
this knowledge.
• It is the result of unifying the information systems and
technology industry’s best engineering practices (principals,
techniques, methods and tools).
• used for both database and software modeling
UML contd…

4. 1. Provide users with a ready-to-use, expressive visual modeling language so they
can develop and exchange meaningful models.
2. Provide extensibility and specialization mechanisms to extend the core concepts.
3. Be independent of particular programming languages and development
processes.
4. Provide a formal basis for understanding the modeling language.
5. Encourage the growth of the OO tools market.
6. Support higher-level development concepts such as collaborations, frameworks,
patterns and components.
7. Integrate best practices.
Advantages of UML

5. Use of UML:
1. To represent complete systems (instead of only the
software portion) using object-oriented concepts
2. To establish an explicit coupling between concepts
and executable code
3. To creating a modeling language usable by both
humans and machines

6. Categories of UML
Structural diagrams: It describes static or structural relationship
among components.
1.Class diagrams: represent the static structure in terms of
classes and relationships.
2. Object diagrams: represent objects and their relationships
and correspond to simplified collaboration diagrams that do not
represent message broadcasts.
3. Component diagrams: represent the physical components of
an application
4.Deployment diagrams: represent the deployment of
components on particular pieces of hardware

7. Behavioral diagrams: It describes behavioral or dynamic
relationship among components.
1. State chart diagrams: represent the behavior of a class in
terms of states at run time.
2. Activity diagrams: represent the behavior of an operation as
a set of actions
3. Use case diagrams: represent the functions of a system from
the user's point of view.
4. Sequence diagrams: are a temporal representation of
objects and their interactions.
5. Collaboration diagrams: spatial representation of objects,
links, and interactions.
Categories of UML

8. Use Case Models [UCM]
• A UCM is a set of scenarios that describing an interaction
between a user and a system.
• This displays the relationship among actors and use cases.
UCM diagram consists of
1. Actor
2. Use cases
3. Dependency relationships between use cases

9. Actor: An actor is anyone or anything that must interact with the
system.
An actor is represented as a stickman.
An actor represents a user or another system that will interact with the
system we are modeling.
Actor Use - Case
UCM contd..

10. Use Case: A use case is an external view of the system that
represents some action the user might perform in order to
complete a task.
Dependency Relationships between Use Cases
1. Extend: Specifies that the target use case extends the behavior of the
source use case.
2. Include: Specifies that the source use case explicitly incorporates the
behavior of another use case at a location specifies by the source. In MS -
Visio, include is termed as uses.
UCM contd..

11. Usage of UCM in three areas:
1. Determining features (requirements). New use cases often
generate new requirements as the system is analyzed and the
design takes shape.
2. Communicating with clients. Their notational simplicity makes
use case diagrams a good way for developers to communicate
with clients.
3. Generating test cases. The collection of scenarios for a use
case may suggest a suite of test cases for those scenarios.

12. For e.g., a user placing an order with a sales company might
follow these steps and generate use case diagram:
1. Browse catalog and select items.
2. Call sales representative.
3. Supply shipping information.
4. Supply payment information.
5. Receive conformation number from salesperson.

13. Order Placement - UCD

14. Class Representations
Class Name
Attributes
Operations

15. END of Part – 1
Chapter -5