软件需求分析英文课件：Chap 6-Design Model

1、Elaboration Iteration 1-Design ModelCh15. UML Interaction DiagramsCh16. UML Class Diagrams 1Chapter 15. UML Interaction DiagramsObjectivesProvide a reference for frequently used UML interaction diagram notation(sequence and communication diagrams).2Sequence and Communication Diagrams The UML include

2、s interaction diagrams to illustrate how objects interact via messages. They are used for dynamic object modeling.3Strengths and Weaknesses of Sequence vs. Communication Diagrams4Example Sequence Diagram: makePayment5Example Communication Diagram: makePayment6Novice UML Modelers Dont Pay Enough Atte

3、ntion to Interaction Diagrams !Most UML novices are aware of class diagrams and usually think they are the only important diagram in OO design. Not true! Although the static-view class diagram are indeed useful, the dynamic-view interaction diagrams are incredibly valuable. Spend time doing dynamic

4、object modeling with interaction diagrams, not just static object modeling with class diagrams.7Common UML Interaction Diagram NotationIllustrating Participants with Lifeline Boxes8Basic Message Expression SyntaxSingleton Objects9Basic Sequence Diagram NotationMessages and focus of control with exec

5、ution specification bar10Illustrating Reply or Returns11Messages to self or this“Creation of Instances12Object Lifelines and Object Destruction13Diagram Frames in UML Sequence Diagrams14common frame operators15Conditional Messages16UML 1.x notational simple styleMutually Exclusive Conditional Messag

6、es17Iteration Over a Collection18Iteration over a collection using relatively explicit notationIteration Over a Collection19Iteration over a collection leaving things more implicitIteration Over a Collection20Nesting of Frames21How to Relate Interaction Diagrams?22Messages to Classes to Invoke Stati

7、c (or Class) Methods23Polymorphic Messages and Cases24Asynchronous and Synchronous Calls25Asynchronous and Synchronous Calls26Basic Communication Diagram NotationLinksMessages27Messages to self or this28Creation of Instances29Message Number Sequencing3031Message Number SequencingConditional Messages

8、32Mutually Exclusive Conditional Paths33Iteration or Looping34Iteration Over a Collection35Messages to a Classes to Invoke Static (Class) Methods36Polymorphic Messages and Cases37Asynchronous and Synchronous Calls38Chapter 16. UML Class DiagramsObjectivesProvide a reference for frequently used UML c

9、lass diagram notation.39Applying UML: Common Class Diagram Notation40Definition: Design Class Diagram411. Definition: ClassifierA UML classifier is “a model element that describes behavioral and structure feature”. Classifier can also be specialized. They are a generalization of many of the elements

10、 of the UMLClasses Interfaces Use cases Actors In class diagram, the two most common classifier are regular classes and interfaces422. Ways to Show UML Attributes: Attribute Text and Association Lines43Idioms in association notation usage in different perspectives44Guideline: When to Use Attribute T

11、ext versus Association Lines for Attributes?45How to Show Collection Attributes with Attribute Text and Association Lines?463. Note Symbols: Notes, Comments, Constraints, and Method BodiesNote symbols can be used on any UML diagram, but are especially common on class diagrams A UML note symbol is di

12、splayed as a dog-eared rectangle with a dashed line to be annotated element; A note symbol may represent several things a UML note or comment, having no semantic impact a UML constraint, must be encased in braces a method body474. Operations and MethodsOne of the compartments of the UML class box sh

13、ows the signature of operationsOperations are usually assumed public if no visibility is shown An operation is not a method. It is a declaration. Method are implementations48How to Show Methods in Class Diagrams?49Operation Issues in DCDsThe create operation The create message in an interaction diag

14、ram is normally interpreted as the invocation of the new operator and a constructor call In a DCD this create message will usually be mapped to a constructor definition, using the rules of the language Operations to Access Attributes Often excluded (or filtered) from the class diagram505. KeywordsA

15、UML keyword is a textual adornment to categorize a model element Most keywords are shown in guillemet ( ) but some are shown in curly braces abstract sample predefined UML keywords include:51Stereotypes, Profiles, and Tags526. Generalization, Abstract Classes, Abstract OperationsGeneralization is a

16、taxonomic relationship between a more general classifier and more specific classifier Each instance of the specific classifier is also an indirect instance of the general classifier. The specific classifier indirectly has features of the more general classifier Is shown in UML with a solid line and

17、fat triangular arrows from the subclasses to supper classes53DependencyIn UML, a dependency relationship indicates that a client element has knowledge of another supplier element and that a change in the supplier could affect the clientThere are many kinds of dependency, here are some common types i

18、n terms of objects and class diagramsHaving an attribute of the supplier type Sending a message to a supplier,the visibility to the supplier Receiving a parameter of the supplier type The supplier is a superclass or interface In class diagrams use the dependency line to depict the following dependen

19、cy between objects global, parameter variablelocal variablestatic-method call5455Example56Another ExampleOptional dependency labels577. Interfaces588. Composition Over AggregationAggregation is a kind of association that loosely suggests whole-part relationship Composition is a strong kind of whole-part aggregation and is useful to show in some models A composition relationship im