24-08-2012, 05:17 PM
Systems Analysis and Design With UML 2.0
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Methods and Messages
Methods implement an object’s behavior
Analogous to a function or procedure
Messages are sent to trigger methods
Procedure call from one object to the next
Encapsulation and Information Hiding
Encapsulation
combination of data and process into an entity
Information Hiding
Only the information required to use a software module is published to the user
Reusability Key
Use an object by calling methods
Inheritance
Superclasses or general classes are at the top of a hierarchy of classes
Subclasses or specific classes are at the bottom
Subclasses inherit attributes and methods from classes higher in the hierarchy
Polymorphism and Dynamic Binding
Polymorphism
A message can be interpreted differently by different classes of objects
Dynamic Binding
Sometimes called late binding
Delays typing or choosing a method for an object until run-time
Static Binding
Type of object determined at compile time