Research And Optimization Of Metadata-Based Software Framework

As the development of software industry, metadata-based software framework is increasingly being used by applications during the process of software development.Compared to traditional software framework, the metadata-based software framework implements the interaction between users and the framework by configurating metadata,which reduces the coupling between the application and the software framework. Most developers regard the function provided by framework as a "black box",the lack of fully understand of the internal design and operational principles makes it is hard for them to fully understand the operational process and the advanced function. An abstract model of metadata-based software framework is proposed in this thesis, and a metadata-based software framework that supports dependency injection and control of requests and responses is implemented guided by the proposed design model to help developers better understand the design and operational principles of metadata-based software framework.Based on the above background, the research of metadata-based software framework is carried out on the following aspects:1. The reasons that metadata is used in software framework are elaborated by the analysis of the existing research and the metadata-based framework on Java. Sprint framework is analyzed in case study, and the operational principle and internal design of Spring IoC are analyzed through source code analysis.2. An abstract model of metadata-based software framework is proposed, which contains three modules according to the function provided by framework during processing:the metadata processing module, the framework service module and the object creation module. Then the architecture style and architecture patterns of each module is designed according to its feature: the metadata processing module is designed with pipes and filters architecture style, the framework service module is designed with layered architecture style and the object creation module is designed with reflection architecture style. The advantages and defects of the module design are elucidated, and improvement suggestions are proposed for the defects. At last, the design of the internal components are elaborated in terms of software design princple and design pattern.3. A metadata-based so ft ware frame work is implemented guided by the proposed model, which several components such as metadata resource identification component, metadata reading component and metadata puzzling component, etc. And Class dependencies and the map between HTTP request and method that Web server responses are described by metadata descriptor in the implemented software framework. In addition, both XML and Java annotations are provided to define metadata in the software framework, so that it is able to automatically establish Class dependency and map HTTP request with response method by metadata configuration4. The implemented software framework is verified, first, two functions supported byte framework is tested, second, a Web-based application system is designed and implemented,and the requirements of employee management in a management system is simulated.Defining metadata by XML and Java annotation solves the common problems in application system development: first, the establishment of the Class dependency in the control layer, the service layer and the persistence layer. Second, the mapping between the client HTTP request and the server response method.In order to solve the problem of repeating work in creating views, data browsing and maintenance, metadata is introduced to describe the entity table and the views are created by framework, so that the efficiency of development is improved. By combining the framework with the application system, the framework is verified effective and the metadata-based software framework model is verified valid.