Chapter 5 - Modeling with classes. In this chapter you will learn about the following: How to properly use the most essential features of UML class diagrams: classes, associations, generalizations and interfaces; the basics of Object Constraint Language (OCL); typical problems you will encounter when modeling with class diagrams; a step-by-step process for systematically developing class diagrams; basic techniques for implementing class diagrams in Java. | Object-Oriented Software Engineering Practical Software Development using UML and Java Chapter 5: Modelling with Classes What is UML? The Unified Modelling Language is a standard graphical language for modelling object oriented software At the end of the 1980s and the beginning of 1990s, the first object-oriented development processes appeared The proliferation of methods and notations tended to cause considerable confusion Two important methodologists Rumbaugh and Booch decided to merge their approaches in 1994. They worked together at the Rational Software Corporation In 1995, another methodologist, Jacobson, joined the team His work focused on use cases In 1997 the Object Management Group (OMG) started the process of UML standardization © Lethbridge/Laganière 2001 UML diagrams Class diagrams describe classes and their relationships Interaction diagrams show the behaviour of systems in terms of how objects interact with each other State diagrams and activity diagrams show . | Object-Oriented Software Engineering Practical Software Development using UML and Java Chapter 5: Modelling with Classes What is UML? The Unified Modelling Language is a standard graphical language for modelling object oriented software At the end of the 1980s and the beginning of 1990s, the first object-oriented development processes appeared The proliferation of methods and notations tended to cause considerable confusion Two important methodologists Rumbaugh and Booch decided to merge their approaches in 1994. They worked together at the Rational Software Corporation In 1995, another methodologist, Jacobson, joined the team His work focused on use cases In 1997 the Object Management Group (OMG) started the process of UML standardization © Lethbridge/Laganière 2001 UML diagrams Class diagrams describe classes and their relationships Interaction diagrams show the behaviour of systems in terms of how objects interact with each other State diagrams and activity diagrams show how systems behave internally Component and deployment diagrams show how the various components of systems are arranged logically and physically © Lethbridge/Laganière 2001 UML features It has detailed semantics It has extension mechanisms It has an associated textual language Object Constraint Language (OCL) The objective of UML is to assist in software development It is not a methodology © Lethbridge/Laganière 2001 What constitutes a good model? A model should use a standard notation be understandable by clients and users lead software engineers to have insights about the system provide abstraction Models are used: to help create designs to permit analysis and review of those designs. as the core documentation describing the system. © Lethbridge/Laganière 2001 Essentials of UML Class Diagrams The main symbols shown on class diagrams are: Classes represent the types of data themselves Associations represent linkages between instances of classes Attributes are simple data
