软件构件与中间件

第一章

1、面向构件的方法

什么是面向构件的方法？

Component-based software engineering (CBSE) is an approach to software development that relies on software reuse –reusing artifacts

面向构件的方法的优点？

Reuse: Development of system = assembly of component

Flexibilit y: Maintenance, replacement of components, extensibility by adding components. May even happen at run-time with proper infrastructure support !

Maintenance and evaluation

面向构件的方法和面向过程、面向对象的方法有什么异同？

Entities for Reuse and Composition

•Abstraction

•Encapsulation

Objects Components Services

•Location: same process

•Inheritance

•Polymorphism

•Location:

different processes,

same environment

•Usually some

runtime

infrastructure

needed

•No state

•No shared

variables

•Location:

different

environments

•More

emphasis on

interface/contract/se

rvice agreement

•Mechanisms

for dynamic

discovery

•Dynamically

composable

基于构件开发的核心思想？

构件模型？

概念：A component model is a definition of standards for component implementation, documentation and deployment

（具体在PPT第一张第33页开始）

第四构件规约

1、构件有哪两方面的不兼容(incompatibility)，如何解决不兼容（课件第四章第8页）

两方面：（1）接口的不兼容(interface incompatibility)包括：参数不兼容，操作不兼容（两个构件中相同操作，有不同名字），操作的不完整性（2）语义不兼容（semantic incompatibility）

如何解决：Interface incompatibility is addressed by writing adaptors（使用适配器）---课件上

（

假设明确化

降低构件耦合度

使用桥、适配器

完善规约说明）----- 自己笔记

2构件的规约层次（四章13页）

Syntax: includes specifications on the programming language level. 语法规约

Semantic: functional contracts 语义规约

Non-functional: deals with quality of service. 非功能性规约

3、构件是如何连接的（四章5页）

4同的概念及为什么要使用合同（第四章22页）

概念：

A set of benefits and obligations that are mutually agreed upon by the client and supplier

为什么要使用合同？

A contract between a client and a supplier protects both sides

It protects the client by specifying how much should be done to get the benefit. The

client is entitled to receive a certain result.

It protects the supplier by specifying how little is acceptable. The supplier must not be

liable for failing to carry out tasks outside of the specified scope.

第五章构件的结合方法

第六章反向控制（六章14页）

第七章语言的透明性和位置的透明性

桩和框架的设计思想

设计题类似本章的例题yellow page

第八章CORBA

注意本章的英文缩写

CORBA:common object request broker architecture 公共对象请求代理体系结构

IDL: interface description language 接口描述语言

ORB：Object Request Broker 对象请求代理

OMG: Object Management group 对象管理组织

OMA: Object Management Architecture 对象管理体系结构

BOA: Basic Object Adapter 基本对象适配器