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OOP / Object-Oriented Programming:
Works with classes and objects within those classes.
Once the class is defined, the attributes can be reused for each new member or instance of the class that is created.
The object encapsulate the attribute values, which means that this information is packaged under one name and can be reused as one entity by other objects.
An object can have a shared portion - The interface that enables it to interact with other components
An object can have a private portion - How it actually works and performs the requested operations
Messages enter through the interface to specify the requested operation or method to be performed.
Information hiding - There is no need for other components to know how each object works internally.
Abstraction - Is the capability to suppress unnecessary details so that the important, inherent properties can be examined and reviewed
Phases of object-orientation:
OORA / Object-Oriented Requirements Analysis -
Defines classes of objects and their interactions.
OOA / Object-Oriented Analysis
In terms of object-oriented concepts, understanding and modelling a particular problem within a problem domain.
DA / Domain Analysis
Seeks to identify the classes and objects that are common to all applications within a given domain.
OOD / Object-Oriented Design
Object is the basic unit of modularity; objects are instantiations of a class.
OOP / Object-Oriented Programming
Emphasizes the employment of objects and methods rather than types or transformations as in other programming approaches.
Features of OOP:
Encapsulation - Hides internal data and operations.
Polymorphism - Makes copies of objects and makes changes to those copies.
Polyinstantiation - Multiple distinct differences between data within objects to discourage lower-level subjects from learning information at a higher-level of security.
Inheritence - Shares properties and attributes.
Multiple inheritence - Is the situation where a class inherits the behavioural characteristics of more than one parent class.
Delegation - Forwarding of a request by an object to another object or delegate. This forwarding is necessitated by the fact that the object receiving the request does not have a method to service the request.
Data Modelling:
Structured analysis approach:
Looks at all objects and subjects of an application and maps the interrelationships, communication paths and inheritance properties.
Data modelling:
Considers data independently of the way that the data is processed and the components that process the data.
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