question: final protected void startQuery ( final IChunkMessage < IBindingSet > msg ) { if ( ! controller ) throw new UnsupportedOperationException ( ERR_NOT_CONTROLLER ) ; if ( msg == null ) throw new IllegalArgumentException ( ) ; if ( ! queryId . equals ( msg . getQueryId ( ) ) ) throw new IllegalArgumentException ( ) ; lock . lock ( ) ; try { runState . startQuery ( msg ) ; } catch ( TimeoutException ex ) { halt ( ex ) ; } finally { lock . unlock ( ) ; } }
target:  Message provides notice that the query has started execution and will consume some specific number of binding set chunks.