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Lesson 11

Class Construction Conclusion

This module discussed how to create compound data types from smaller types using classes. You learned that classes are user-defined data types, and that objects are instances of those classes.
In general, there may be zero, one, or more instances of any given class. Classes have attributes, and objects provide particular values for each attribute.
You also learned how to represent classes, objects, and their attributes in Unified Modeling Language (UML)-style diagrams, and how to draw a diagram that represents the relationships among classes.
You simply create objects of your existing class inside the new class. This is called composition because the new class is composed of objects of existing classes.

Composition syntax



Glossary

This module introduced you to the following terms:
  1. Anonymous object
  2. Attribute
  3. Boolean
  4. Class diagram
  5. Composition over inheritance:Composition over inheritance (or composite reuse principle) in object-oriented programming is the principle that classes should achieve polymorphic behavior and code reuse by their composition (by containing instances of other classes that implement the desired functionality) rather than inheritance from a base or parent class
  6. Field
  7. Function
  8. Member variable: In object-oriented programming, a member variable (sometimes called a member field) is a variable that is associated with a specific object, and accessible for all its methods (member functions).
  9. Method
  10. Object diagram:
  11. Primitive:
  12. UML:

The next module will discuss the characteristics of operations and methods in classes and how to diagram them.

UserDefined Data Types - Quiz

Click the Quiz link below to review the concepts introduced in this module.
UserDefined Data Types - Quiz