Modularitet och objektorientering
Byggandet av ett program som kan visa en molekyl
The development of IT systems is usually accomplished by some form of system development methodology. It can be performed as the waterfall method, where each phase is completed before the next begins. One of the reasons to follow a development methodology is that the process is more structured, faster and that the product will have higher quality. One risk of not using a system development approach is that the code can be unstructured and difficult to maintain.This paper describes an alternative method in which the development occurred without the use of any system development methodology. This has been possible because there was a clear goal of the program that should be developed. The goal was to read a molfile and from the information stored in the file plot the molecular structure. The appearance of the molecule has been fine-tuned as more features are added. A molfile is able to store all the information about the different characteristics a molecule can have. Not all molecules containing all the properties.Development has proceeded as follows: Each property has been classified as an object and then implemented. The whole way from reading the property in the file into the computer program and then interpret the information to plot the property as a part of the molecule. The most important programming principle has been to develop the program as a number of more or less independent modules for the system to have high modularity.