Web services review
Overview
Web services are self-contained, modular applications that we can describe, publish, locate, and invoke over a network.
This document provides a procedure for reviewing extant Web services
Task Status What types of Web services are currently implemented? WAS supports Web services developed using the Web Services for Java EE specification, including... Are annotations currently in use?
Is V6.1 Feature Pack configured?
A typical Web services scenario is a business application requesting a service from another existing application. The request is processed through a given Web address using...
- SOAP messages over a HTTP
- JMS transport
- Invoked directly as EJB
The service receives the request, processes it, and returns a response. Examples of a simple Web service include weather reports or getting stock quotes. The method call is synchronous, that is, the method waits until the result is available. Transaction Web services, support things like...
- quotes
- business-to-business (B2B)
- business-to-client (B2C) operations
- airline reservations
- purchase orders
Web services can include the actual service or the client that accesses the service.
The inter-library loan program at the local library is a good example of the Web services concept. We can search the local library collection and other local libraries at the same time. When other libraries provide the library with a Web service to search their collection (UDDI), the results yield their resources. We might use another Web service application to check out and send the book to the home.
Web services reflect the service-oriented architecture (SOA) approach to programming, based on the idea of building applications by discovering and implementing network-available services, or by invoking the available applications to accomplish a task. Web services applications allow components created in different programming languages to work together, relying on existing transport technologies, such as HTTP, and standard data encoding techniques, such as XML, for invoking the implementation.
The key components of Web services include:
WSDL XML-based file used to describe and bind the Web service request. SOAP XML-based protocol used by Web service requests to invoke the service. UDDI Registry that hosts the service broker.
For a concrete example, see Web services scenario: Overview, which tells the story of a fictional online garden supply retailer named Plants by WebSphere, and how this retailer incorporated the Web services concept.
Subtopics
Web Services for Java EE specification
Artifacts used to develop Web services
JAX-WS
JAXB
JAX-RPC
WS-I Basic Profile
WS-I Attachments Profile
Related tasks
Use the UDDI registry Enable Web services through service integration technologies
Use WS-Notification for publish and subscribe messaging for Web services
Related
Web services specifications and APIs