G4UA::SyncPrimaryGeneratorAction Node1 G4UA::SyncPrimaryGenerator Action   + SyncPrimaryGeneratorAction() + GeneratePrimaries() Node2 G4VUserPrimaryGeneratorAction     Node2->Node1 Node3 IG4RunTool   + DeclareInterfaceID() + NotifyBeginRun() + WaitBeginRun() + Size() + PushEvent() + GetEvent() Node3->Node1 -m_g4RunTool Node4 IAlgTool     Node4->Node3