Research And Implementation Of Software Design Pattern Library

Design patterns are common solutions for certain problems of software design. Using design patterns is good not only for the expansibility and reusability of software, but also for reducing the cost of software development and maintenance, so reuse of design patterns is a primary form of software reuse.Existing key technologies and theories of implementing design pattern library are analyzed and summarized, including design pattern classification, description, storage, search, instantiation, automation, and etc. Pattern search and pattern instantiation are the most important parts of design pattern library, so they are paid great attention to in this paper. According to definition and measurement of pattern similarity, a pattern search algorithm based on the match of design pattern motive is brought forward. At the same time, in terms of the one-to-many case of the conditions for search and design patterns, the paper presents the concept and computational method of match degree, which facilitates the similarity sort of search results. When the decent design patterns are searched out, how to generate advisable solutions which combined the requirements and design patterns, this involves the design pattern instantiation. Each design pattern has the stability of algorithm framework and the variability of user requirements, according to the theory, a method of pattern instantiation based on Velocity template is put forward in the paper.Finally, in accordance with the ideas just mentioned, the paper proposes a solution for building automation tool of design patterns, which is grounded on for DPStore system. As an important part of SoftStore, DPStore is a container for storage and management of design patterns, which supports references and reuse of design patterns. It can help developers utilize successful development experience and implement abstract design pattern reuse. Borrowing ideas from zero Programming, the users just need input the requirement and essential data of design problem, DPStore can generate a propositional solution which applies suitable patterns.