question: @ Override public PollResult startPoll ( PollController conn ) { if ( ! _lifecycle . isActive ( ) ) { log . warning ( this + " select disabled" ) ; return PollResult . CLOSED ; } SocketBar socket = conn . getSocket ( ) ; if ( socket == null ) { log . warning ( this + " socket empty for " + conn ) ; return PollResult . CLOSED ; } SelectableChannel selChannel = socket . selectableChannel ( ) ; if ( selChannel == null ) { log . warning ( this + " no channel for " + socket ) ; return PollResult . CLOSED ; } _connectionCount . incrementAndGet ( ) ; _activeCount . incrementAndGet ( ) ; _registerQueue . offer ( conn ) ; return PollResult . START ; }
target:  Adds a keepalive connection.