【作者】 邵伟峰；

【导师】 吕强；

【作者基本信息】 苏州大学 ， 计算机软件与理论， 2006， 硕士

【摘要】 本文介绍了一个协同编辑环境下结构化文档版本管理系统的设计过程,并在一个真实的协同编辑器Z-Office上完整地实现了该系统。XML文档版本管理最主要的目的在于有效存储连续修改的XML文档,减少存储的成本,快速获取保存的所有历史版本,以及提供查询的功能。Z-Office文档格式是对XML的一种自定义扩展。本文首先研究了文档变化检测X-Diff算法,接着分析了SPaR编码方案及其版本机制,然后在此基础上对文档节点编码方案进行了改进。具体来说就是利用空间性和时间性的概念,针对Z-Office文档,为其树形文档结构上的每个节点位置进行稀疏编码并赋予节点生存区间以及其它一些附属信息,然后在文档增量存储上使用了本文提出的文档更新维护算法,使得改进后的方案不需要往前或往后推算即可直接获取任意版本的Z-Office文档。最后在多版本文档的查询上,将文本检索技术、结构化连接算法引入本系统,提供了关键字查询、精确查询以及比较查询。从而本文完整地提供并实现了一个版本管理系统。更多还原

【Abstract】 This paper introduces a design of structural document version management system which implements in a real cooperative editor (Z-Office).The main purposes of version management of XML documents are to efficiently store a frequently modified XML document, reduce the storage costs, retrieve previous versions of the XML document with quick response, and provide mechanism querying Multi-Version XML documents. Z-Office provides its document format which instantiates XML specification. This paper therefore presents a solution to versionize such documents.Firstly, this paper studies and analyzes algorithm X-Diff, and the related SPaR numbering schema for version control mechanism are analyzed. Secondly, an improvement in document node numbering is presented. Both temporal and spatial views are taken account into creating sparse position number, lifespan and other node properties for every document node in the tree document structures of Z-Office. And a new algorithm based document update maintenance is proposed and implemented in the system. With the support of these works, Z-Office can retrieve all versions efficiently and quickly. Therefore Z-Office needs not to restore the version forward and backward. Finally, for the Multi-Version document query, this paper makes use of text search technology and structural join algorithm so as to support search based on key words, accurate search and comparative search. All the work above realizes a complete version management system for a real cooperative editor.更多还原