<<collaboration scenario collaborationdiagram_1:
1) actor 'customer' sends message "stock value query" to object 'internet browser'
2) object 'internet browser' sends message "ask value to app server" to object 'application server'
3) object 'application server' sends message "ask value to db" to object 'database server'
4) object 'database server' sends message "return value from db" to object 'application server'
5) object 'application server' sends message "return value from app server" to object 'internet browser'
6) object 'internet browser' sends message "return value" to actor 'customer'>>
结论
有了这一强大特性，我们能够为 robustness 结构图方法提供全面的支持，扩展了对象的概念，并基于新的概念添加了新的符号和约束，尤其是特定的文字生成。
