工作流引擎Bossa学习

    在应用程序调用引擎时，是通过BossaFactory类生成一个对象，并通过此对象创建一个引擎实例：

BossaFactory factory = new BossaFactory();

        factory.setStateDir("build/BossaBrowserState");

        bossa = factory.createBossa();

    包含四个主要的Manger:

        1.caseTypeManager 

* This class manages all registered case types of the workflow

        * system. It provides all the case type life cycle functions and

 * is the entry point of the WFNet package.

        2.resourceManager

        * This class manages the creation and removal of resources.

        * Resources are groups of resources, indexed by a string id.

* Single users are empty resources, their presence indicates the

* id is in use.

        3.workManager

        * This class manages the generation of work item lists.

        4.historian

        * This class keeps the historical records of a Bossa engine. 
    把Bossa的源程序，在Jbuilder中跟踪调试，其UML图主要如下: