Chapter 5: UML Class Diagrams

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• Chapter 5 UML Class Diagrams

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• Objective
• Provide a reference for frequently used UML class
  diagram notation.

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5.1. Applying UML Common Class Diagram Notation
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5.2. Definition Design Class Diagram
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5.3. Definition Classifier

• A model element that describes behavioral and
  structure features
• Regular Class
• Interface

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5.4. Ways to Show UML Attributes

• Ways to Show UML Attributes
• Attribute text notation,.
• Association line notation
• Both together
• Full format of the attribute text notation
• visibility name type multiplicity default
  property-string

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5.4. Ways to Show UML Attributes
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5.4. Ways to Show UML Attributes

• Attribute-as-association line styles
• a navigability arrow pointing from the source to
  target object,
• a multiplicity at the target end, but not the
  source end
• a rolename only at the target end to show the
  attribute name
• no association name

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5.4. Ways to Show UML Attributes
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5.4. Ways to Show UML Attributes

• When to Use Attribute Text vs. Association Lines
  for Attributes?
• Use the attribute text notation for data type
  objects
• Use the association line notation for others
• Emphasize the connection between the class of
  objects

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5.4. Ways to Show UML Attributes
public class Register private int id
private Sale currentSale private Store
location //
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5.4. Ways to Show UML Attributes

• The UML Notation for an Association End

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5.4. Ways to Show UML Attributes

• public class Sale
• private ListltSalesLineItemgt lineItems
• new ArrayListltSalesLineItemgt()
  
• //

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5.5. Note Symbols

• UML note or comment
• have no semantic impact
• UML constraint
• encased in braces ''
• method body
• the implementation of a UML operation

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5.6. Operations and Methods

• Operations
• visibility name (parameter-list) return-type
  property-string
• getPlayer( name String ) Player exception
  IOException
• public Player getPlayer( String name ) throws
  IOException
• How to Show Methods in Class Diagrams?
• in interaction diagrams
• by the details and sequence of messages
• in class diagrams
• with a UML note symbol stereotyped with method

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5.6. Operations and Methods

• Operation Issues in DCDs
• The create Operation
• Operations to Access Attributes
• often excluded (or filtered)

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5.7. Keywords

• Textual adornment to categorize a model element
• Most are shown in guillemet ( )
• Some are shown in curly braces ( )

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5.8. Stereotypes, Profiles, and Tags

• Stereotypes
• shown with guillemets symbols .
• represents a refinement of an existing modeling
  concept
• defined within a UML profile
• UML profiles
• a collection of related stereotypes, tags, and
  constraints to specialize the use of the UML for
  a specific domain or platform
• Tags
• apply to the Stereotype element
• can be assigned values

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5.8. Stereotypes, Profiles, and Tags
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5.9. UML Properties and Property Strings

• Property
• a named value denoting a characteristic of an
  element
• Property string
• Format
• name1value1, name2value2

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5.10. Generalization, Abstract Classes, Abstract
Operations

• Generalization
• A taxonomic relationship between a more general
  classifier and a more specific classifier.
• Each instance of the specific classifier is also
  an indirect instance of the general classifier.
• Abstract classes and operations
• shown either with an abstract tag
• italicizing the name
• Final classes and operations
• shown with the leaf tag

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5.11. Dependency

• Dependency Relationship
• a client element has knowledge of another
  supplier element
• a change in the supplier could affect the client.
• Common Types
• having an attribute of the supplier type
• sending a message to a supplier the visibility
  to the supplier could be
• an attribute, a parameter variable, a local
  variable, a global variable, or class visibility
  (invoking static or class methods)
• receiving a parameter of the supplier type

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5.11. Dependency

• Used to depict following dependency between
  objects
• global
• parameter variable
• local variable
• static-method.

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5.11. Dependency
public class Sale public void
updatePriceFor( ProductDescription description )
Money basePrice description.getPrice
() // //
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5.11. Dependency
public class Foo public void doX()
System.runFinalization()
// //
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5.11. Dependency
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5.12. Interfaces
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5.13. Composition Over Aggregation

• Aggregation
• a vague kind of association in the UML that
  loosely suggests whole-part relationships.
• Composition
• a strong kind of whole-part aggregation
• implies
• an instance of the part belongs to only one
  composite instance at a time,
• the part must always belong to a composite
• the composite is responsible for the creation and
  deletion of its parts.

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5.13. Composition Over Aggregation
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5.14. Constraints

• UML Constraint
• restriction or condition on a UML element.

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5.15. Qualified Association

• Qualified Association
• used to select an object (or objects) from a
  larger set of related objects
• based upon the qualifier key

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5.16. Association Class

• Association Class
• treat an association as a class,
• model it with attributes, operations, and other
  features

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5.17. Singleton Classes
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5.18. Template Classes and Interfaces

• templatized types,
• templates, parameterized types, and generics

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5.18. Template Classes and Interfaces

• public class Board
• private ListltSquaregt squares
• new ArrayListltSquaregt()
• //

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5.19. User-Defined Compartments
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5.20. Active Class
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5.21. What's the Relationship Between Interaction
and Class Diagrams?
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• Questions Answers