This paper presents a group of strategies based on transaction mechanism for the coordination of the multi-services' dynamic updating in a service-oriented distributed system. These strategies included a selection strategy for choosing of security updating time-point and a 2PC (two-phase-commit) strategy for controlling the multi-services' updating. With the analysis of time, needed by related updating operation steps, this paper suggests that the basic updating operations (including creation of service instances, orderly execution of multiple service instances' runtime state-convertion, redirection of service-request-message and activation of new services) should be controlled in a short updating transaction, and multiple persistent data conversions should be controlled orderly under a long transferring transaction (every persistent data conversion should be controlled in a short transaction). The goal is that with the help of transaction mechanism, the world will expect to ensure system state's ACID properties before and after updating it as efficiently as possible. Furthermore, to make of the most of the correct updating of system, this paper researches about automatically producing and updating transaction, data conversion transaction, and serializing among application transactions and conversion transactions. In the last section, this paper gives a prototype validation of the strategies based on Apache CXF-DOSGi.%就面向服务的分布式系统中多服务动态更新的协调问题,提出基于事务控制的更新协调策略,包括安全更新时机的选择策略、使用2PC(two-phase-commit)协调多服务更新的控制策略.根据更新实施的各步操作时间开销,提出分别采用更新短事务控制基本更新操作(包括创建服务实例、顺序实施运行时状态转换、重定向服务请求和新服务的激活操作)和转换长事务控制多组持久数据转换操作(其中每组持久数据转换由一个相应的短事务控制)的更新实施策略,以期借助于事务的控制机制尽可能高效地保证更新前后系统运行状态的ACID特性.就事务控制策略的自动实施做了一定的研究工作,包括:根据更新描述脚本自动生成更新短事务操作序列、根据持久数据关联构件的依赖关系分析自动生成各个持久数据转换短事务序列组成的长事务以及对应用事务和各转换事务的序列化处理.最后,通过基于Apache CXF-DOSGi的原型实现对给出的控制策略进行了可行性验证.
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