Mapping URLs to Web Components

When it receives a request, the web container must determine which web component should handle the request. The web container does so by mapping the URL path contained in the request to a web application and a web component. A URL path contains the context root and, optionally, a URL pattern:

http://host:port/context-root[/url-pattern]

You set the URL pattern for a servlet by using the @WebServlet annotation in the servlet source file. For example, the GreetingServlet.java file in the hello2 application contains the following annotation, specifying the URL pattern as /greeting:

@WebServlet("/greeting")
public class GreetingServlet extends HttpServlet {
    ...

This annotation indicates that the URL pattern /greeting follows the context root. Therefore, when the servlet is deployed locally, it is accessed with the following URL:

http://localhost:8080/hello2/greeting

To access the servlet by using only the context root, specify "/" as the URL pattern.