Mode And Reconstruction In The Framework Of Object-oriented Software Applications

Industrialized Software reuse has been envolved from general class libraries to domain-oriented application framework.The biggest benefit from framework is reuse. Framework is the largest reuse style that object-oriented system can obtain.The lifecycles of the object-oriented software can divided into several phases. Brain Foote distinguishes it with prototype phase, Expansionary phase,and Consolidation phase[12] These three phases are also go with the process of software envolution and the enhance of reuse degree. The object-oriented software framework is often evolvedfrom software prototype.A framework is a set of cooperating classes that make up a reusable design for a specific class of software[1] The framework dictates the architecture of your application, developer can customize a framework to a particular application by creating application-specific subclasses of abstract classes from the framework.The design patterns descriptions of communicating objects and classes that are customized to solve a general design problem in a particular context. A design pattern names, abstracts, and identifies the key aspects of a common design structure that make it useful for creating a reusable object-oriented design. Refactoring is a change made to internal structure of software to make it easier to understand and modify without changing its observable behavior[11].Metapatterns describe design patterns on a meta leval[3]. The metapattern represents a way for designers of systems to pass on knowledge on an even more abstract level than regular design patterns do. As such the metapattern is an invaluable tool for the development of for example frameworks.The software prototype we discussed in this thesis is based the Approval Subsystem of ERP system for Zhejiang Kangyu Pharmaceutical Co., Ltd.,it is applied to handler the various application sheets in the company with unified approval platform.The main operational flows are applying process,approving process,and system management. This software prototype is modeled by UML language using Rational Rose, and is implemented upon J2EE platform. There are three main charecteristics: the separation of application main table with application detail table,the separation of approval node with approver, and support customized approval flow. According to the design targets of the framework, this framework must extends the software prototype in three aspects. First,adding new functions,mainly supporting to web applicationn and supporting to historical data transfer. Second,improving the original design,include building the inheritance system for applicaion sheets,making strategy for a new flow node,and supporting the various database connections.we implemente the tasks by using three design patterns,they are Abstract Factorypattern,Strategy pattern and Template Method pattern. Third,Refactoring for the design and programming disfigurements which exists in the software prototype everywhere. In this thesis I will list some big granulated refactoring: Extract class,Inline class,move method,Collapse Hierarchy to remove unnecessary Hierarchy, and Introduce parameter object to remove long parameter list.By using pattern and refactoring, the original software prototype has been obtained the basic characteristics of framework. So we can get the conclusion that with the use of pattern and refactoring in the process of framework development ,we can make framework more flexible, and more easy to be expanded and maintained.