Main Pagehttp:/pg-server.csc.ncsu.edu/mediawiki/index.php/CSC/ECE 517 Fall 2009/wiki2 7 cn: Difference between revisions
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=='''Maintenance points'''== | =='''Maintenance points'''== | ||
Duplicating code is the result of a copy-paste scenario. The second you’ve copy-pasted a module of code to two locations in your application you’ve just created an additional maintenance point. Though this can’t always be avoided, I highly suggest you do if you don’t want to be looking for all the places you have a cache being filled up with data to save load times (for example). Not only that, if you coded a bug into the “beautiful” piece you pasted everywhere, now that bug is also in every place you pasted it! | |||
=='''Interfaces'''== | =='''Interfaces'''== | ||
Revision as of 23:11, 7 October 2009
Problem Statement
Different languages have different mechanisms for "code reuse". Assembly and low level languages have macros, C/C++ has includes, Ruby has mixins and modules, Java has packages, and there are many other concepts around reuse and extension. Here is a page that describes the various mechanisms, groups the mechanisms into logical categories, and discusses the advantages and disadvantages of the various schemes, in terms of simplicity, performance, reliability, or other factors.
A Brief Overview of Code Reuse
Code reuse, also called software reuse, is the use of existing software, or software knowledge, to build new software.Code reuse is the idea that a partial or complete computer program written at one time can be, should be, or is being used in another program written at a later time. The reuse of programming code is a common technique which attempts to save time and energy by reducing redundant work.The software library is a good example of code reuse. Programmers may decide to create internal abstractions so that certain parts of their program can be reused, or may create custom libraries for their own use. The following sections elaborate more on code reuse.
Code Reuse is not Duplication
Reuse is different from duplication.In code reuse you can relocate the logic or work that a module does in multiple areas of the application to one place. It doesn’t have to physically reside in all of those places to get reused.
Maintenance points
Duplicating code is the result of a copy-paste scenario. The second you’ve copy-pasted a module of code to two locations in your application you’ve just created an additional maintenance point. Though this can’t always be avoided, I highly suggest you do if you don’t want to be looking for all the places you have a cache being filled up with data to save load times (for example). Not only that, if you coded a bug into the “beautiful” piece you pasted everywhere, now that bug is also in every place you pasted it!
Interfaces
References
http://www.refactoring.com
Refactoring: Improving the Design of Existing Code by Martin Fowler.
References
http://www.refactoring.com
Refactoring: Improving the Design of Existing Code by Martin Fowler.