系统分析与设计——活动图画法

简介

一个UML活动图表示一个过程中的多个顺序活动和并行活动。这些活动图有助于对业务过程、工作流、数据流和复杂算法进行建模。活动图包括动作 action、分区 partition、分叉点 fork、连接点 jion、对象节点 object node等。本质上，此图显示了一些列 的动作，动作可以并行。

案例

Screenshot 1 

demonstrates that “Reserve Hotel” is part of a larger web-based solution for all sorts of travel reservations and arrangements. From the viewpoint of “Reserve Hotel” these should be treated as external functions with no dependencies to “Reserve Hotel”. Screenshot 1 demonstrates also that the online traveler/customer is asked to type in the destination city, select the check in date and either specify the number of nights or select the check out date. The Search button allows to submit the request to the system to find available hotels on the dates specified.

Screenshot 3 

shows a web page resulting from a successful search. The page shows:

• workflow that informs that making a reservation consists of four steps: (1) search, (2) choose hotel, (3) choose room type, and (4) confirm reservation
• summary that displays the original search criteria
• search again option, which returns the customer to Screenshot 1
• option to sort results by: (1) our favourites, (2) lowest price, (3) highest star rating, and (2) alphabetical
• search results listing the hotels and basic information about them, as well as the continue option to proceed with the reservation

分析思路

活动图的分析思路，关键在于找到合理的业务逻辑，分类出简洁的业务过程，或者说是业务过程建模。这里 需要注意，需求 文档中往往会列出很多操作或者按钮，但是并不代表都是一个业务过程，我们应当提炼相似的操作，或者目的一样的操作，统一到一个业务事件上。如：

Screenshot 1 

demonstrates that “Reserve Hotel” is part of a larger web-based solution for all sorts of travel reservations and arrangements. From the viewpoint of “Reserve Hotel” these should be treated as external functions with no dependencies to “Reserve Hotel”. Screenshot 1 demonstrates also that the online traveler/customer is asked to type in the destination city, select the check in date and either specify the number of nights or select the check out date. The Search button allows tosubmit the request to the system to find available hotels on the dates specified.

对于界面1，红色字体标出了，关键的业务过程就是填写资料和提交信息。虽然填写的项目有很多 ，但是这都是为一个目的服务，就是描述要搜索的房间，所以这里统一为一个业务事件。

Screenshot 3 

shows a web page resulting from a successful search. The page shows:

• workflow that informs that making a reservation consists of four steps: (1) search, (2) choose hotel, (3) choose room type, and (4) confirm reservation
• summary that displays the original search criteria
• search again option, which returns the customer to Screenshot 1
• option to sort results by: (1) our favourites, (2) lowest price, (3) highest star rating, and (2) alphabetical
• search results listing the hotels and basic information about them, as well as the continue option to proceed with the reservation

对于界面3，工作流描述了关键的业务过程，这里可以直接利用，由于 search动作时上一个页面的动作，所以这里的只有2--3的业务过程。

作图