Red Hat SummitChapter 28. Connecting objects
28.1. Connecting Objects
Connecting object connect two elements. There are two main types of Connecting object:
- Sequence Flow, which connect Flow elements of a Process and define the flow of the execution (transport the token from one element to another)
- Association Flow, which connect any Process elements but have no execution semantics
28.2. Connecting Objects types
28.2.1. Sequence Flow
A sequence flow represents the transition between two flow elements. It establishes an oriented relationship between activities, events, and gateways, and defines their execution order.
- Condition Expression
When this condition evaluates to
true, the workflow takes the sequence flow.If a sequence flow has a gateway element as its source, you need to define a conditional expression that is evaluated before the sequence flow is taken. If evaluated to
false, the workflow attempts to switch to another sequence flow. If evaluated totrue, the sequence flow is taken.When defining the condition in Java, make sure to return a boolean value:
return <expression resolving to boolean>;
- Condition Expression Language
- You can use either Java, Javascript, MVEL, or Drools to define the condition expression.
When defining a Condition Expression, make sure to call process and global variables. You can also call the kcontext variable, which holds the process instance information.
