中间件复习笔记汇总.docx

2015年-11月-13日INTRO概念一类独立的系统软件和服务程序A class of standalone system-level software and services procedures在操作系统的顶部Working on the top of OS管理计算机资源和网络Managing computational resources and network communications支持分布式通信Supporting distributed apps功能在异构的网络环境中，涉及到跨连通性和可操作问题中提供统一的协议和接口Providing standardized interfaces and protocols隐藏实现细节Hiding implementation details提高程序的可移植性Increasing the portability of apps放置于操作系统和数据库管理系统的顶部为高级应用的开发和执行提供环境Providing environments for the execution and development of higher-level apps协助软件工程师灵活高效地开发和集成复杂的分布式软件Assisting software engineers in flexibly and efficiently developing and integrating complex distributed software中间件发展的主要因素隐藏异构型Hiding heterogeneity硬件异构hardware heterogeneity操作系统异构 OS heterogeneity数据库异构 database heterogeneity支持可操作性supporting inter-operability不同的平台 different platforms不同的网络协议 different network protocols不同的通信机制 different communication mechanisms提高软件的复用率 improving efficiency and quality of software development主要类别远程过程调用中间件RPC remote procedure call middleware对象请求代理中间件ORB object request brokers middleware面向信息中间件 MOM message-oriented middleware数据库访问中间件 DAM database access middleware事务处理中间件TPM transaction processing middlewareRMI对象请求代理ORB提供一个框架，使得远程对象可以在网络中以同样的方式使用在网络中的本地对象Providing a framework where remote object can use local objects in the same way over the network当对象在客户端和服务器之间传递时，提供功能的编组和解组的功能Providing functionalities for marshalling and unmarshaling when objects are transmitted between clients and servers.客户端和服务器之间的传输隐藏实现的细节,这使得开发人员能够有效地实现分布式应用程序，而无需面对复杂的底层操作系统和网络通信Hiding the implementation details,which enable developers to implement distributed apps efficiently without facing the complex underlying operating systems and network communicationsJAVA RMI 的概述用java编写分布式对象Writing distributed objects using java直接用java对象来为分布式计算机建模Simple and direct model for distributed computation with java objects以java为中心，由此带来了安全性和分布式计算的可移植性Centered around java, thus bringing the power of Java Safety and portability to distributed computing行为可以被转移动Behavi