INTERACTIVE WEB SERVICES WITH JAVA

UDDI - Universal Description, Discovery, and Integration

- a step higher than WSDL in the protocol stack

UDDI (400 page spec): a Web service registry mechanism
- "a meta service for locating Web services by enabling robust queries against rich metadata"

UDDI business registration: XML files used to describe business entities and their Web services
- white pages - business address, contact info, etc.
- yellow pages - industrial categorizations based on standard taxonomies (allows search within particular industry, product category, geographical region, ...)
- green pages - more technical information, for instance WSDL descriptions
UDDI also provides a SOAP+WSDL-based registry API for registering ("publish") and discovering ("inquire") Web services.

Some tools:

a cool UDDI browser (try searching for "amazon" in the XMethods registry)
UDDI4J - open-source Java implementation of UDDI (included in WSTK)
Microsoft's free UDDI registry