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Within a XUI rule it's possible to define own actions to get fired. Conditions get checked if an event occurs, if the condition is true all corresponding actions are fired(ECA, Event-Condition-Action).
Instead of using the built in actions (uiActions), one can provide an own action implementation. If a predefined UI action is choosen in combination with an custom action implementation, both actions will be fired. The inverse action is usually a inverse implementation of the main action. 
Implementation Info
The class need to implement the Action interface: com.jaxfront.core.rule.Action
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