1. Theoretical Model
According to my personal imagination, simple has the meaning of Simplicity. Therefore, this name is used to express the meaning of the pattern. It is actually an XOR merge.
XOR-join: This mode only accepts one branch and follows the first come, first served principle. If either A or B is completed, C is executed. There is a problem left over. If the front is the and branch, what about the node that is executed later? The actual application of the process design is involved here. We will discuss this issue in more detail when talking about other join modes.
2. Application
This mode is mainly used to cope with the process with only one branch in front of the body. This mode is also a very common mode. In many flowcharts, what is not explicitly stated can generally be regarded as XOR-join, that is, the completion of any front body triggers the next work unit.
The general consideration is a kind of overall thinking. This model has a precondition that it is "safe ". The so-called security means that the previous process must ensure that A and BYes and onlyOne will be executed. If both A and B are possible, this mode should not be used. For example, thread merge mode is available (this mode will be described later ).
3. Extend
The five modes we have mentioned so far have been explained in detail (sequence, parallel split, synchronization, exclusive choice, and simple merge), which are the basic process control modes. These modes serve as the foundation of the workflow system, and almost every workflow engine has direct support. The following two modes of application do not involve too much content, because the combination of the basic workflow mode and the application are described separately.