Java Web Services: Up and Running, 2nd Edition

What Good Are Web Services?

This obvious question has no simple answer, but the benefits and promises of web services can be clarified with examples. The first example underscores how the distinction between websites and web services continues to blur: the data and functionality available at one can be available at the other. (One web framework that emphasizes the blurring is Rails, which is discussed in more detail later.) The second example focuses on how web services can be used to integrate diverse software systems and to make legacy systems more widely accessible.

A visit to a website such as the Amazon E-Commerce site is often interactive: a shopper uses a browser to search the Amazon site for desired items, places some of these in a shopping cart, checks out the cart, finalizes the order with a credit card or the equivalent, and receives a confirmation page and usually an email. Pioneers in web services, such as Amazon, expose the information and functionality of websites through web services as well. Searching and shopping against Amazon, as code examples in later chapters illustrate, are tasks that are automated readily because Amazon makes a point of coordinating its websites with its web services. In any case, here is a sketch of how a search-and-shop experience might be automated.

1. A shopper has a database table or even a simple text file, wishList.txt, that contains items of interest such as books, movies, or any other search-and-shop category that Amazon supports.