Description of problem: Java samples are configured for using user name "username" and password "password". The default SASL database contains user "guest" with password "guest". This means that java samples cannot be run unless broker authentication is disabled or user "username" is added to the SASL database, Solution: I believe the best way of solving that is to update the java sample URLs with user name guest, password guest.
See qpid-1134 (closed): Sample URLs are now amqp://guest:guest@clientid/test?brokerlist='tcp://localhost:5672'