Conclusion
From Andrey
| Revision as of 03:49, 4 February 2006 Andrey (Talk | contribs) ← Previous diff |
Revision as of 04:01, 4 February 2006 Andrey (Talk | contribs) Next diff → |
||
| Line 1: | Line 1: | ||
| The main point of this article is to consider the nature of an '''object's behavior as consisting of two aspects''': the general behavior, provided by its class, and the behavior specific to a particular context in which the object is used. Conceptually, overriding in owner class is the '''''mechanism for separating the object's behavior specific to a particular context (role) from the behavior specific to its class'''''. Thus, overriding in owner class introduces a '''different way to organize the code defining the behavior'''. Looking at the examples within this article, one can see that it can make it easier to accomplish a variety of tasks, such as: | The main point of this article is to consider the nature of an '''object's behavior as consisting of two aspects''': the general behavior, provided by its class, and the behavior specific to a particular context in which the object is used. Conceptually, overriding in owner class is the '''''mechanism for separating the object's behavior specific to a particular context (role) from the behavior specific to its class'''''. Thus, overriding in owner class introduces a '''different way to organize the code defining the behavior'''. Looking at the examples within this article, one can see that it can make it easier to accomplish a variety of tasks, such as: | ||
| - | * to enforce class invariants concerning a member, as is done in the example with ''lee_jeans''; | + | * to enforce class invariants concerning a member, as is done in the example with [[Definition_of_Overriding_in_Owner_Class#Lee_jeans|''lee_jeans'']]; |
| * to create an object managing two-way input and output, as is done in the example with ''visual_cash''; | * to create an object managing two-way input and output, as is done in the example with ''visual_cash''; | ||
| * to solve the updates issue, as is done in the example with ''working_girl''; | * to solve the updates issue, as is done in the example with ''working_girl''; | ||
Revision as of 04:01, 4 February 2006
The main point of this article is to consider the nature of an object's behavior as consisting of two aspects: the general behavior, provided by its class, and the behavior specific to a particular context in which the object is used. Conceptually, overriding in owner class is the mechanism for separating the object's behavior specific to a particular context (role) from the behavior specific to its class. Thus, overriding in owner class introduces a different way to organize the code defining the behavior. Looking at the examples within this article, one can see that it can make it easier to accomplish a variety of tasks, such as:
- to enforce class invariants concerning a member, as is done in the example with lee_jeans;
- to create an object managing two-way input and output, as is done in the example with visual_cash;
- to solve the updates issue, as is done in the example with working_girl;
- to write a class for immediate reuse without implementing all the minor details, as in the example with circular_gauge;
- to simplify and "objectify" the interface of a class, as in the example with int_property.
Overriding in owner class can affect the way you create the designs, particularly in how you set up objects of unrelated classes to work together; how the processing of an action is split from its cause; how reusable classes are written. I think that this approach will help minimize dependencies between classes; reduce their need for updates; avoid redundant subclassing and dynamic structures; provide fuller control over class members. The ease with which this mechanism fits into C++ and the fact that it does not, in my opinion, create inconsistencies in the language makes me think that it logically and usefully extends the language.
Acknowledgments
I am grateful to Vitaly Shmatikov for reviewing the draft of this paper and helping in its improvement.
References
[1] A. Potekhin “Implementation of Overriding in Owner Class.” [[1]]
[2] E. Gamma et al., “Design Patterns, Elements of Reusable Object-Oriented Software”
