Working with RESTful Web Services
In the nineties the Web became widely used, and newly created web applications were consumed by millions of people around the world. At the same time lots of legacy applications were available for use only within corporate walls. They were written in a variety of programming languages and deployed on a plethora of types of hardware. There was a need to expose corporate data to wider audiences, which resulted in the creation of the standard interface for consuming data over the Web.
The SOAP Web Services
The first standard for publishing and consuming web services was the XML-based Simple Object Access Protocol (SOAP). Web clients would form HTTP requests and receive responses using the SOAP syntax.
The difference between traditional JSP/Servlet/JSF web applications and web services is that the latter offer just the data and have no interest in what the client’s UI will look like. For example, an insurance company could offer information about its products, or a mutual fund could expose its data as a web service returning XML documents. Clients didn’t need to know that this insurance company was running its applications using a server from Sun Microsystems or that the mutual fund was running its on mainframe computers from IBM. The clients needed to know the directory of services available from this particular organization and the address of the endpoint to connect to in order to consume this service.
The directory of services could ...