Research And Implementation Of Asset Retrieval In Reusable Asset Management System

With the development of software industry, demands for software rapidly increase and scales of software systems also grow. Thus, more and more software enterprises have realized the importance of software reuse. The most effective method of software reusing for software enterprises is to reuse software assets of their own. The reusable asset management system, which is based on reusable asset specification presented by OMG, implements the functions of asset description, asset storage and asset retrieval. How to retrieve assets in the system is a main problem when we design the reusable asset management system. A proper retrieval method will effectively reduce the costs of retrieval. On the contrary, a rough method will make the use of system more difficult and results in a failure of software reuse.According to the situation of software reuse in domestic software enterprises and requirements from enterprises, this paper proposes keyword retrieval based on asset manifests and domain faceted retrieval. Keyword retrieval method is suitable for enterprises during their rookie days of reusable asset management system implementation. The other is suitable for enterprises during their mature days. These two retrieval methods will be adapted to the growth of developers' software reusing experience. This paper mainly focuses on the implementation of these two retrieval methods. During the research, we improve some mature retrieval methods and apply them to the reusable asset management system.Firstly, the paper researches on reusable asset specification and creates asset manifests based on it. Asset manifests are XML files and contain metadata of assets. We create the descriptions of asset keywords and facet terms under the classification element in asset manifest. These descriptions are used to create inverted lists of asset.Secondly, the paper researches on extracting keywords from asset manifest, encoding asset manifest and creating inverted list. When researching on extracting keywords, we propose a method of manually defining keyword list, which can avoid a word-extracting dictionary of software reusing, and we use a directed word segment algorithm to realize extracting keywords from sentences. To help users catch the most related information of assets, the paper researches how to find the keywords smallest common ancestor in a manifest tree by analyzing Dewey id of nodes. To sort the result of retrieval, we research on calculating the correlation between asset and keyword list, which depends on keywords statistics and their positions in asset manifest.Morever, the paper proposes an improvement on the traditional facet scheme. After analyzing the shortage of traditional facet scheme, we present a domain facet scheme based on FODA (Featured Oriented Domain Analysis), which has three layers. Each layer in this facet scheme corresponds to a phase of FODA, and terms in each layer correspond to terms in context model, feature model and architecture model. Concerning implementation of domain faceted retrieval, terms in facet always have relationship of ancestor and descendant. To reflect this relationship among terms in matching assets, we encode the facet manifest to realize finding all descendants of one term, creating matching-term list and calculating term weights.Lastly, the paper introduces how we design the modules of asset retrieval. We implement these modules as models of MVC framework.