of the workflow template to drive the workflows. The
Workflow Manager will check whether the load time of the
template is matched with the configuration file, if it finds
that the last modification time of the template in the
configuration file is not consistent with the one when the
system loads the template, the Workflow Manager will reload
the template and return the latest model, if there is no
change, then just load the model. The Workflow Manager
has been designed as the Singleton Pattern, all the
management and storage of the models are thread safety.
C. Workflow Driver
The main function of the Workflow Driver is to drive the
workflow instances according to the internal model. Through
the above internal model storage structure, we can see that
the internal model is organized as the tree structure, all the
leaf nodes are the executable parts, and all the non-leaf nodes
are the logical controlled container nodes.
Like the Workflow Manager, the Workflow Driver is also
designed in the Single Mode; all the operations are thread
safety.