Procedural paradigm: Software is organized around the notion of procedures Procedural abstraction —Works as long as the data is simple Adding data abstractions —Groups together the pieces of data that describe some entity

Software is intangible Hard to understand development effort Software is easy to reproduce Cost is in its development —in other engineering products, manufacturing is the costly stage

7.1 User Centred Design Software development should focus on the needs of users Understand your users Design software based on an understanding of the users’tasks Ensure users are involved in decision making processes

一、名词解释 1、会计电算化 2、软件工程 3、快速原型法 4、甩帐

1. 为什么要使用设计模式 要真正掌握软件设计，必须研究软件设计大师的成功设计，这些设计中 包含了许多设计模式。 定义：一个设计模式是对某特定环境下的某类问题 的解决方法。 使用设计模式的好处：

Abstract Model Specifications Build an abstract model of required software behavior using mathematically defined(perhaps using axioms )types(e. g sets, relations) Define operations by showing effects of that operation on the model Specification includes Model

1. 使用UML进行数据库设计 数据库建模传统方法：E-R图。仅对数据建模，不能对行为建模，如触发器、存储过程等建模

Outline: Software Design Goals History of software design ideas Design principles Design methods Life belt or leg iron?(Budgen)

1.类的定义 Rumbaugh对类的定义是： 类是具有相似结构、行为和关系的一组对象的描述

1.交互图(interaction diagram) 交互图 顺序图