A subflow is a chain of message processors processed synchronously that can be referenced and reused through a Flow Reference Component.
A flow can reference several subflows to complete synchronous processing tasks, and a subflow can have several triggering flows.
The only property that a subflow node can take is name. This is a mandatory nonBlankString value that is used to identify the subflow in order to reference it from your flow reference component.
XML Editor or Standalone
A representation of a subflow in XML looks something like this.
<flow name="mainFlow">
<flow-ref name="subFlow" doc:name="Flow Reference"/>
</flow>
<sub-flow name="subFlow">
</sub-flow>
Note that the Flow Reference connector points to the sub-flow node named subFlow.