Software Reuse In The Process Of Software Development

In the age of 60s, the "software crisis" made the programmers clear that software maintenance is costly or even unacceptable, especially when the software become more and more huge and complexity. Even more those huge cost can't make the software work well. The principle of software reuse is a basic way to resolve that problem.No one can comprehend every side of a software system as it become more and more huge and complexity. Software is built up on the base of reuse; reuse is the basic property of software. Developers are beginning to know the important of software reuse and the existence of a great deal of repeat works in the process of software development. Those repeat works may be existed in the document writing or code writing or testing and so on. So as the decrease of those repeat works by improving the software reuse, the time cost will decrease and quality of the software will improve. In the process of software develop; developer can reuse many existed materials, so it can reduce many repeat works in many sub process such as software analyzing, designing, coding, testing and so on. At the same time, to reuse the high quality existed materials can avoid errors which may be happen in the new development, so the software's quality will be improved. A report of HP cooperation say that: there were only 0.9 KLOC bugs in the reused code, but the KLOC of new code is 4.1; for a software system which include 68% reused code, the KLOC is 2.0 compare to the software with no reused code, the expected quality will be improved 51%.In the past, people only focus the software reuse to the code writing. And the key point to improve software reuse is how to reduce repeat code writing and how to improve the intelligence of IDE. From the assembly language to C language and to Object Oriented language, from function library to class library and to COM and .Net, from Notebook to Microsoft Visual Studio 2005, code reuse had been dramatically improved and the repeat works in coding also had been dramatically decreased. As a result, the process of software development became fast and the quality of the software improved. But only the code reuse can hardly make even more effect on the speed of development and quality of software, and also can hardly match the regular change of the user demand. In the software engineering, coding is only a small process in the entire project. Only make reuse in the entire project, can we get more speed and quality, can we server customer well. This paper is base on this concept that reuse is not only the code reuse, but to consider the whole project to find reuse chance then make the reuse chance happened by using technology and management methods.