private void handleCommand ( MetaCommand cmd ) throws IOException { if ( cmd == null ) { return ; } switch ( cmd ) { case MetaCommand_Nothing : break ; // Leader master requests re-registration case MetaCommand_Register : setIdAndRegister ( ) ; break ; // Unknown request case MetaCommand_Unknown : LOG . error ( "Master heartbeat sends unknown command {}" , cmd ) ; break ; default : throw new RuntimeException ( "Un-recognized command from leader master " + cmd ) ; } }
Handles a leader master command .