Subflow sample code for spring web flow 2.3.1.RELEASE

 The outer flow's path:
       src/main/webapp/WEB-INF/flows/outer/outer-flow.xml

 The inner flow's path:
       src/main/webapp/WEB-INF/flows/inner/inner-flow.xml


Inside outer flow:


    <subflow-state id="current-step" subflow="inner">
        <input name="actionrequest" value="100" type="java.lang.String"/>
        <transition on="submit" to="next-step"/>
    </subflow-state>

Inside inner flow:

    <input name="actionrequest"/>
    <view-state id="select-customer" >
        <transition on="submit" to="submit"/>
    </view-state>

    <end-state id="submit" commit="true" />