IT 21103/41103 System Analysis & Design
Chapter 05 Object Modeling
Chapter 05 Object Modeling combines the DFD & ERD into one
Chapter 05 Object Modeling in Small Enterprise Systems is rare, but driven by object-programming
Chapter 05 The Design & Development Phases of the System Analysis are dependent on good modeling in the Analysis Phase
Chapter 05 Object Modeling is vital if you plan to program with Object based development tools
Chapter 05 Objects Have two components: AttributesBehaviors
Chapter 05 Attributes Equal to Fields in a Database
Chapter 05 Behaviors Composed of program instructions called Methods
Chapter 05 Methods Respond to events by other users or other objects
Chapter 05 Object-Oriented Analysis (OOA) Identifying objects and how they work together to produce information
Chapter 05 Objects:ClassInstanceEncapsulationMessagesPolymorphismInheritanceRelationships
Class: Abstract of a real-world PersonPlaceThingActivity
Chapter 05 Class: Two Components Data Attributes Fields in a Database Methods Services performed by the class member
Chapter 05 Instance: A specific Person, Place, Thing or Activity Created from the Class Template
Chapter 05 Encapsulation: The environment where the Class lives Functions associated with Methods
Chapter 05 Encapsulation: Methods have two types: #1 Perform input/output services To communicate with other objects outside the membrane
Chapter 05 Encapsulation: Methods have two types: #2 Perform behavior services to manipulate data inside the membrane
Chapter 05 Messages: How objects communicate with each other ( )
Chapter 05 Polymorphism: Methods can change their behavior depending on the Class they belong with
Chapter 05 Inheritance: Class attributes and methods are inherited by a newly created class
Chapter 05 Relationships: How Classes Interact with each other Inherit attributes & methods Cardinality between classes
Chapter 05 An analyst would not need to produce a DFD or ERD if doing object modeling
Chapter 05 Object Relationships: Collaborative Relationship Specialization Relationship Aggregation Relationship
Chapter 05 Collaborative Relationship: One Class provides information to another Class
Chapter 05 Specialization Relationship: A Class is a sub-set of another Class, where it inherits all of the Parents attributes & methods, but may have a few that the Parent does not “Is A”
Chapter 05 Aggregation Relationship: When one Class is composed of one or more Instances of another Class “Has A”
Chapter 05 Use Case Modeling: Developing a model based on task scenarios to determine what happens in a particular system A detailed description of what happens when something interacts with a system
Chapter 05 Object Modeling Symbols SymbolCardinality Zero or One Only One Zero or Many One or Many
Chapter 05 Object Modeling Symbols Object Name Attributes Methods
Chapter 05 Unified Modeling Language (UML) Nine Types
Chapter 05 Class Diagram Object Diagram Use Case Diagram Interactive (Sequence) Diagram Interactive (Collaboration) Diagram Statechart Diagram Activity Diagram Component Diagram Deployment Diagram
Chapter 05 Data Dictionary Contains the Data element names and their characteristics This is part of the documentation required for the SDLC
Chapter 05 Object Diagram Shows specific instances of classes (Figure 5-9 – page 134)
Chapter 05 Questions?
Assignment # 5 Page 139 UML – Object Diagram Due: Oct 19 th, 2005