This chapter covers
- Consuming RSS and ATOM feeds
- Using REST and JAX-RS
- Remote operations with XML-RPC
- SOAP Web Services
Service to others is the rent you pay for your room here on earth.
Muhammad Ali
From the early days of computer networking, we’ve used a wealth of protocols and data formats to allow computers to interact and exchange information. With the popularity and ubiquity of the World Wide Web, the range of protocols and data formats has consolidated to primarily focus on HTTP, which implements the request–response model you know from your everyday browsing activities, and a small number of markup notations (mainly HTML, XML, and JSON) as the data-exchange format. These are the commonly called web service technologies and are the subject of this chapter.
At a simple level, sharing data happens every time you surf the web. With the help of your browser, you request a URL. The server responds with an HTML document that your browser knows how to display. The server and the browser are interconnected through the HTTP that implements the request–response model, and they use HTML as the data-exchange format.