Java Reference
In-Depth Information
27. logger.info("Welcome home! The client locale is {}.", locale);
28.
29. Date date = new Date();
30. DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG,
DateFormat.LONG, locale);
31.
32. String formattedDate = dateFormat.format(date);
33.
34. model.addAttribute("serverTime", formattedDate );
35.
36. return "home";
37. }
38.
39. }
Line 17
: The
@Controller
annotation is used to specify that this class is a Spring
controller.
DispatcherServlet
scans such annotated classes for mapped handler
methods by means of
@RequestMapping
annotations.
Line 25
: The
@RequestMapping
annotation specifies that the
home()
method will
handle a GET request with the URL / (the default page of the application).
Line 26 to 37
: The
home()
method creates a
String
object to hold the current
date based on the current locale and adds this object to the model with the
name
serverTme
. And finally the method returns a view named
home
, which will
be resolved by the view resolver specified in the
servlet-context.xml
file, to
find the actual view file. In one controller class, we can write many methods to
handle different URLs.
@Controller
and
@RequestMapping
and a number of other annotations form the basis for the Spring
MVC implementation. To define a controller class in Spring 3.0 and newer, you have to mark the
class with the
@Controller
annotation. When an
@Controller
-annotated class receives a request,
it looks for an appropriate handler method to handle the request. Each method to which the request
is to be mapped is decorated with the
@RequestMapping
annotation, making the method a handler
method to which the request is mapped by means of handler mappings.
As you saw in Listing 5-38, the
home()
method in
HomeController
returns a view named
home
, which
is resolved by the view resolver specified in
servlet-context.xml
. Now it is time to look at the view,
which is the
home.jsp
file generated in the
/WEB-INF/views
directory. Listing 5-39 illustrates
home.jsp
.
Listing 5-39. home.jsp of the Hello World Application
1. <%@ taglib uri="
http://java.sun.com/jsp/jstl/core
"
prefix="c" %>
2. <%@ page session="false" %>
3. <html>
4. <head>
5. <title>Home</title>
6. </head>
7. <body>
8. <h1>
9. Hello world!
10. </h1>
