question: public void consumeDocuments ( String topicName , int count , long timeout , TimeUnit unit , Runnable completion , BiPredicate < String , Document > consumer ) { AtomicLong readCounter = new AtomicLong ( ) ; consumeDocuments ( continueIfNotExpired ( null , timeout , unit ) , completion , Collections . singleton ( topicName ) , null ) ; }
target:  Asynchronously consume all messages on the given topic from the cluster.