Specification Obligation to provide a connection between objects Implementation

Specification obligation to provide a connection

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Specification : Obligation to provide a connection between objects Implementation : Object pointers, references, linking structures, etc.
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Coming up: Association Names Associations Student Class Section Course Semester Instructor Department takes> is registered for> teaches> sponsors> <works for is instance of> is held d uring>
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Coming up: Navigation Association Names Associations may be named The names should communicate the meaning of the links The names are typically verb phases The name should include an arrow indicating the direction in which the name should be read
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Coming up: Navigation Navigation The navigation of associations can be uni-directional bi-directional unspecified Class Section Course Instructor Department teaches> sponsors> <works for is instance of>
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Coming up: Generalization Generalization Generalization is another kind of relationship in UML – see Meta Model From an analysis perspective, it is a pure generalization/specialization concept, i.e., the specialization is a subset of the generalization Student Person Graduate Student
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Coming up: Generalization Generalization From a specification/implementation perspective, generalization can represent sub- typing, inheritance, type capability, and substitutability (depends on the language) Student major: String GPA: Real standing: String add(Class Section) drop(Class Section) Person name: String address: String changeAddress(new_address)
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Coming up: Class Diagrams Exercise – Simple Associations From an analysis perspective: Identify meaningful associations and generalization/specializations among classes in the Elevator System
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Coming up: Class Diagrams Class Diagrams Class Diagrams describe the types of objects in a system their properties (attributes and operations) relationships between objects They can also include Grouping concepts like packages Constraints Various kinds of annotations
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Coming up: Multiplicity Constraints Multiplicity Constraints Student Class Section Course Semester Instructor Department takes> is registered for> teaches> sponsors> <works for is instance of> is held d uring> 1..* 1 1..* 1..* 1 1 1..* 0..8 0..* 0..6 1..3
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Questions From the previous diagram How many classes can a student take? Do you have to be registered in any classes to be a student? Do I need to teach this class to be an Instructor? Do I need to teach ANY classes?
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Coming up: Dependencies Multiplicity Constraints A multiplicity constraint can be a single number a “*”, meaning an arbitrarily large number or simply “many” a range, denoted by “min..max” a sequence of single numbers and ranges
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Coming up: Dependencies Dependencies Relation A consolidated snippet of the UML Meta-model Association Generalization Dependency Aggregation Binary Association N-ary Association
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Coming up: Dependencies Dependencies A dependency is a type of relationship It says that one modeling component “uses” another.
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