Research And Application Of Design Pattern In Information System

Structured programming has been replaced by object-oriented software design gradually, and the latter becomes the mainstream method of software design, but the unavoidable contradiction in software development, such as software requirement changes, makes great challenge with reusability and extensibility which object-oriented software method self required.Pattern came from building field that are developing in OO field during last 10 years, offers strong support for meeting the challenge. Design pattern has been introduced into as a kind of thought way in Software Engineering, Almost all good structural object-oriented software contains design pattern in architecture. It is a kind of reuse means at design level, Shalloway and Trott proposed the concept of pattern context analysis, emphasized the complexity of "special context"(defined by design pattern) development in design pattern, as well pointed out we should apply pattern according to the context nest order of many patterns existed in systematic requirement in order to make them close combination to build stable system.In this paper, we limited the content of object-oriented reuse firstly, mainly studied the support of object-oriented analysis and design, then we analyzed the limitation of traditional object-oriented viewpoint, finally we researched object-oriented reuse based on software design pattern, discussed the design pattern support to reuse from object creation, structure and behavior, and described how to support transplant, expansibility and the reuse of software during the design process.On the foundation of analyzing object-oriented and design pattern thoughts, we discuss its application strategy and principle seriously. Let us use sort system as an example to demonstrate how to carry out selecting a design pattern and design with the method of pattern. Then, a company management information system as project background, we analysis how to recognize design pattern through requirement analysis and how to combined in an optimized order according to context analysis, which avoid an isolated application of design patterns and ensure the reliability, reusability and extensibility of software system.