Object-oriented Design Of Three-tier Application System And In The Resident Population Of The System

Distributed 3-tired C/S model and Object Oriented techniques are broadly apppied in many fields for their advantages. But program developers and designers encounter a lot of problems in process of software development and designment. This paper's topic is to develop a distributed 3-tier Client/Server Information System with Object Oriented techniques.This paper mainly includes 2 parts: theoretic part(6 models for application layer structures and 3 models for muti-tier C/S DataConstraints) and Practical part(parts of Resident Management Information System designment). The following are details.The paper mainly analyzes the key designment of distributed 3-tier Client/Server: application layer designment with Object Oriented technique % designment DataConstraints of muti-tier C/S and layout for 3-tier C/S model. Based on a model for application layer structure that Control Object invoked by Client-End and is divided according to client transaction and object's mention, some models are brought forward . Model for Entity Object Access DB ? Model for Entity Object Access DB through Access Object and Model for Entity Object Access DB through Data Object are brought forward according to the way of Entity Object accessing Data layer. Model for centralization and Model for relation are brought forward according to relation between Entity Objects.There are 6 models by combining these possibilities. 7 potential DataConstraints designment models are analysed and 3 applicable designment models for muti-tier C/S DataConstraints are brought forward for designer and developer .They are ApplicationLayer+DB , ClientLayeH-ApplicationLayer and 3 Layers.Parts of a practical system?Resident Management Information System designment are given. IDCard Management % Approvement Management % Query Module are modued with UML and designed by modues brought forward. Some problems ecountered in system designment are analyzed and discussed and then above theories analyses are strengthened and unproved.Some factors are considered and improved in the analyses and designment that are reuse, maintenance, expansibility> performance* efficiency, speed % opening, security, reliability and so on. Influences brought by those factors are analysed and discussed. Some errors often made by developer and designer are brought forward and resolvement ways are.given.