An Introduction to Java and Program Design - Java Programming: Comprehensive Concepts and Techniques - page 9

it, and returns a response to the application. A typical example of a Web service
is that of an automatic stock quote service, in which the request asks for the cur-
rent price of a specified stock, and the response returns the stock price. Another
example might be a service that maps out an efficient route
for the delivery of goods. In this case, a business application sends a request
containing the delivery destinations, and a Web service processes the request to
determine the most cost-effective delivery route.
FIGURE 1-7
JavaBeans
Java also can be used to create components for use by other programs.
Such a component, called a JavaBean or simply a bean , is a reusable software
component developed in Java, which can be used by any application that under-
stands the JavaBeans format. Beans allow programmers to develop applications
visually using standard development tools. Beans provide the benefit of
reusability , which means they can be used over and over in many programs
developed by different programmers. A bean also can store data and retrieve
it later. For example, a bank account bean might store an account number and
balance. A programmer might write code to display the bean's properties on a
secure Web page when the customer requests his or her balance. Figure 1-8 on
the next page displays a development tool used to create JavaBeans.