My impression is that UDDI is not used, by and large. And where it is used, it's within companies, where there are probably better ways of advertising WS. WS as a whole have not (yet?) taken the direction UDDI was designed to address - assembling higher-order services from publicly available building blocks. There is no marketplace of competing WS for which it would make sense to publish them through a directory.
Well, that's how UDDI was supposed to be used. There were a few large public repositories, but they were closed due to lack of interest, mostly. I wouldn't spend time on UDDI (unless you need it for the exam).
Note that there is not even a working group for the UDDI standard any longer, so it likely won't evolve any further in the foreseeable future.
Generally you would publicize the WSDL of the service(s), and point to it from some web page that explains how to use the service. Or you'd publicize the WSDL, but send its address only to those people you want to be able to connect to it. In the latter case you should also use some form of authentication.
It's still possible to use UDDI, of course. There are two java libraries that implement it (jUDDI and UDDI4j).
Those preparing for SCDJWS, I suggest to use jUDDI for practical experience on UDDI and JAXR programming. Though, I caught up some problems in running samples, I still manage to work using jUDDI's nice user interface to send/receive SOAP messages for publish/inquiry. Thanks and Regards, Naren
(OCEEJBD6, SCWCD5, SCDJWS, SCJP1.4 and Oracle SQL 1Z0-051)
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