Web services are distributed application components that conform to standards that make them externally available. They solve the problem of integrating diverse computer applications that have been developed independently and run on a variety of software and hardware platforms. The proliferation of distributed environments has created a need for an enterprise to be able to expose all or part of the functionality of an application to other applications over an open network.
The promise of web services architecture is to allow you to connect applications that were developed on different platforms and in different programming languages. This can only work if vendors can agree on common standards.
There are two distinct web service programming models, both of which are supported by the IDE, the first is specific to the Java EE 5 specification, while the second is specific to the J2EE 1.4 specification:
For further information on JAX-WS web services, see About JAX-WS Web Services
For further information on JAX-RPC web services, see About JAX-RPC Web Services
Both programming models are based on the following three specifications:
SOAP (Simple Object Access Protocol). Defines the mechanism by which a web service is called and how data is returned. For detailed information, refer to the SOAP 1.1 Specification.
WSDL (Web Service Definition Language). Describes the external interface of a web service. For detailed information, refer to the WSDL 1.1 Specification.
UDDI (Universal Discovery, Description, and Integration) Registries contain information about web services, including the location of WSDL files and the location of the running services. The IDE does not let you publish web services to or browse from a UDDI registry, although the WSDL files that you use can come from a variety of sources, including a UDDI registry.