Convience class that should be used when a Java delegation in a BPMN 2.0
process is required (for example, to call custom business logic).
This class can be used for both service tasks and event listeners.
This class does not allow to influence the control flow. It follows the
default BPMN 2.0 behavior of taking every outgoing sequence flow (which has a
condition that evaluates to true if there is a condition defined) If you are
in need of influencing the flow in your process, use the
class 'org.activiti.engine.impl.pvm.delegate.ActivityBehavior' instead.