Uml Detailed Class Design

DETAILED CLASS hanh-at-hueuni.edu.vn DESIGN

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Dr. Hoang Huu Hanh, OST – Hue University

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Hue University

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Objectives To

describe the determining of class’s operations. To describe a template for class interface specifications

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Designing Class Operations It

is usually easy to determine class’s operations from the dynamic models of the systems, in particular, from the interaction diagrams.

 When

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two objects interact, one object provides an operation that is used by the other object. is also necessary to consider

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Example of Entity Class  Analysis

model: collaboration diagram

 Design

model: collaboration diagram

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Example of Output Device Interface Class        

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an initialize operation to initialize5

Example of State Dependant Control Class       

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Support

two generic operations

◦ processEvent ◦ currentState

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Example of Business Logic Class

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Further Categorization of Entity Classes

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During

design, a decision has to be made whether the data encapsulated by an entity class is to be managed directly by the entity class or whether the data is actually to be stored in a database. ◦ ◦ Data abstraction classes (transient) ◦ ◦ Database wrapper classes 8

Examples of Data Abstraction Class

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Example of Database Wrapper Class        

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Class Interface Specifications

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Class type (class structuring criterion) Assumptions Anticipated changes Superclass (if applicable) Inherited operations (if applicable) Operations provided by the class. For each operation, define, ◦ Function performed ◦ Precondition ◦ Postcondition ◦ Invariant ◦ Input parameters ◦ Output parameters ◦ Operations used from other classes 11

Thank you!

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