UML and Classes, Objects and Relationships / PDF

UML and Classes, Objects and Relationships  / PDF

Software Development Process and Unified Modeling Language (UML)

nA software development process is a set of phases that are followed to bring a product or a system from conception to delivery.

nIn the Unified Process, there are four of these phases:

nInception (Analysis phase)

nidentify the system we are going to develop, including what it contains and its business case.

nUML: use-case diagrams

nElaboration (Design phase):

nperform detailed design and identify the foundation of system from “use case diagram”, which eventually lead to classes.

nUML: classes, objects, class diagrams, sequence diagram, collaboration diagrams etc.

nConstruction (Implementation phase): write software using Java/C++

nthe actual building of the product from the design of the system.

nTransition (Rolling out phase): Deliver the system/product to the users. Includes maintenance, upgrades, and so on until phasing out.

Object Oriented Design (OOD)

nOOD is the technique used to architect software with groups of classes that interact with one another to solve a problem.

nTo qualify as an OOD, a few requirements need to be met.

nThe three fundamental principles are essential for an OOD to exist:

nClasses (abstraction and encapsulation)

nInheritance

nPolymorphism

n+ OO notions: packages, exceptions, streams, threads, components and events (asynchronous notifications), and communicators (sockets).

Modeling a class in UML

nWhen modeling a class in UML, we have a lot of flexibility.

nThe same class can be modeled in four different ways:

nWith no attributes or operations shown

nWith only the attributes shown

nWith only the operations shown

nWith both the attributes and operations shown

nThe name of the class is always the first component of the class box; in fact, it is the only required component, as we have seen in our earlier discussion (OOP in Java).

Notes:

nClass  - The rectangle is the icon for the class. The name of the class is, by 

convention, a word with an initial uppercase letter. It appears near the top of the 

rectangle. If your class name has more than one word name, then join the words 

together and capitalize the first letter of the every word.

 nAttribute  - An attribute is a property of a class. It describes a range of 

values that the property may hold in objects of the class. A class may have zero 

or more attributes. A one-word attribute name is written in lowercase letter. If 

the name consists of more than one word, the words are joined and each word 

other than the first word begins with an uppercase letter. The list of attribute 

names begins below a line separating them from the class name.

nOperations :  An operation is something that a class can do, or that you (or 

another class) can do to a class. Like an attribute name, an operation's name is 

written in lowercase letter. If the name consists of more than one word, the 

words are joined and each word except the first word begins with an uppercase 

letter. The list of operations begins below a line separating operations from the 

attributes.....

UML and Classes, Objects and Relationships  / PDF