G4UA::SyncEventActionTool Node1 G4UA::SyncEventActionTool   # makeAndFillAction() Node2 G4UA::UserActionToolBase < SyncEventAction > # m_actions + UserActionToolBase() + fillUserAction() + BeginOfAthenaEvent() + EndOfAthenaEvent() # makeAndFillAction() Node2->Node1 Node3 extends< AthAlgTool, IUserActionTool >     Node3->Node2