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| The Movement To Objects Systems analysis and design, 6th edition Dennis, wixom, and roth Roberta M. Roth © Copyright 2015 John Wiley & Sons, Inc. 0 Learning Objectives Explain the basic concepts of the object approach and UML. Be able to create a use case diagram. Be able to create a class diagram. Be able to create a sequence diagram. Be able to create a behavioral state machine diagram. © Copyright 2015 John Wiley & Sons, Inc. 1 1 Basic OO Characteristics © Copyright 2015 John Wiley & Sons, Inc. 2 What is “object-oriented”? The object-oriented approach views a system as a collection of self-contained objects, including both data and processes. Object-oriented systems focus on capturing the structure and behavior of information systems in modules (objects) that encompass both data and processes. © Copyright 2015 John Wiley & Sons, Inc. 3 3 Classes and Objects Class: the general template used to define and create specific instances, or objects. An object: an instantiation of a class. | The Movement To Objects Systems analysis and design, 6th edition Dennis, wixom, and roth Roberta M. Roth © Copyright 2015 John Wiley & Sons, Inc. 0 Learning Objectives Explain the basic concepts of the object approach and UML. Be able to create a use case diagram. Be able to create a class diagram. Be able to create a sequence diagram. Be able to create a behavioral state machine diagram. © Copyright 2015 John Wiley & Sons, Inc. 1 1 Basic OO Characteristics © Copyright 2015 John Wiley & Sons, Inc. 2 What is “object-oriented”? The object-oriented approach views a system as a collection of self-contained objects, including both data and processes. Object-oriented systems focus on capturing the structure and behavior of information systems in modules (objects) that encompass both data and processes. © Copyright 2015 John Wiley & Sons, Inc. 3 3 Classes and Objects Class: the general template used to define and create specific instances, or objects. An object: an instantiation of a class. An object is a person, place, event, or thing about which we want to capture information. Each object has attributes that describe information about the object. © Copyright 2015 John Wiley & Sons, Inc. 4 4 © Copyright 2015 John Wiley & Sons, Inc. 5 Classes and Objects (cont’d) Messages and Methods Methods implement an object’s behavior. A method is an action that an object can perform. Messages are information sent to objects to trigger methods. © Copyright 2015 John Wiley & Sons, Inc. 6 Messages and Methods, con’t. © Copyright 2015 John Wiley & Sons, Inc. 7 Encapsulation and Information Hiding Encapsulation: the combining of process and data into a single entity. Information hiding: only the information required to use a software module be published to the user of the module. © Copyright 2015 John Wiley & Sons, Inc. 8 Inheritance Inheritance is used to identify higher level, or more general, classes of objects. Common sets of attributes and methods can be organized into superclasses.