protected void checkPreconditions ( List < ConsumerHolder > consumerHolders ) throws IOException { Channel channel = createChannel ( ) ; for ( ConsumerHolder consumerHolder : consumerHolders ) { String queue = consumerHolder . getConfiguration ( ) . getQueueName ( ) ; try { channel . queueDeclarePassive ( queue ) ; LOGGER . debug ( "Queue {} found on broker" , queue ) ; } catch ( IOException e ) { LOGGER . error ( "Queue {} not found on broker" , queue ) ; throw e ; } } channel . close ( ) ; }
Checks if all preconditions are fulfilled on the broker to successfully register a consumer there . One important precondition is the existence of the queue the consumer shall consume from .