No mapping found for HTTP request with URI?

问题:

Hi I have the following code: Controller:

@Controller

public class HelloWorldController {

    @RequestMapping("/hello")
        public ModelAndView HelloWorld() {
            String message = "My First SpringMVC Program ";
            return new ModelAndView("hello","message",message);
        }

web.xml

<servlet>
            <!-- load on startup is used to determine the order of initializing the servlet when the application
            server starts up. The lower the number, earlier it starts -->
            <servlet-name>spring</servlet-name>
            <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
            <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>spring</servlet-name>
        <url-pattern>*.html</url-pattern>
    </servlet-mapping>

spring-servlet.xml

<context:component-scan 
base-package="org.example.controller"/>

<bean id="viewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView">
</property>
<property name="prefix" value="/WEB-INF/jsp/">
</property>
<property name="suffix" value=".jsp"></property>

When I run this code, I get the following warning "WARNING: No mapping found for HTTP request with URI [/SpringDemo/Hello.html] in DispatcherServlet with name 'spring'". What wrong am I doing?

回答1:

Your web.xml says all requests with url pattern *.html are forwarded to Spring. Your @RequestMapping only filters on /hello, but the request url reaching Spring is /hello.html. What you are missing is the .html. Your @RequestMapping should be /hello.html.

After your request goes through your controller you are forwarding to a view named hello, and the configuration in your spring-servlet.xml resolves this to hello.jsp in WEB-INF/jsp, so make sure you have that as well.

Happy coding!