Research And Application Of Classical Design Patterns In ERP Software Of Commercial Domain

Software reusability is always the goal for the software people. It can improve the productivity and quality of software. In order to reuse software, we use design pattern to record software design knowledge, because it can improve software reusability from code reusing to every phases of developing.Software design patterns are the elements of reusable object-oriented software. They describe reusable design solutions and experiences in a systematic and specific way. Design patterns identify, name, and abstract common themes in object-oriented design. They capture the intent behind a design by identifying objects, their collaborations, and the distribution of responsibilities.I experienced three software projects (CWMMIS, MZMIS and CPMIS), and through the developing processes I realized the essential of design patterns and the forms of their reusability. This paper discusses seven classical design patterns' application in Enterprise Resource Planning (ERP) of commercial domain. They are Container, Adapter, TemplateMethod, Strategy, State, Mediator and Interpreter. Especially to Strategy and State, there are deeper discussions.Aided with Strategy, we not only get its initial purpose of encapsulating a series of complicated algorithms so they can replace each other, but also grasp another advantage that it helps resolve the multiple-hierarchy problem in designing objects. Using State pattern, we can classify objects dynamically. This is special important in context of billstate- oriented commercial domain. Inspired by this pattern, I propose an advanced solution for designing the outbill objects in our software system.