Java - HTTP Status 404 – Not Found

Question

I'm studying spring mvc and want to test some very simple annotation-based controllers,It works fine on home page but when I enter /home/user it gives me HTTP Status 404 – Not Found error and I haven't found anything to fix it.

web.xml

<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/applicationContext.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!--####################################-->


    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>2</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <welcome-file-list>
        <welcome-file>redirect.jsp</welcome-file>
    </welcome-file-list>
</web-app>

dispatcher-servlet.xml

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd">

    <bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping"/>

    <context:component-scan base-package="spring" />

    <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>

    <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>

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

    <!--<bean id="viewResolver"

</beans>

HomeController.java

package spring.controllers;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
//@RequestMapping(value = "/home")
public class HomeController {

    @RequestMapping(value = "/home", method = RequestMethod.GET)
    public String showHomeMessage() {
        return "home";
    }
}

UserController.java

package spring.controllers;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
@RequestMapping("/home/user")
public class UserController {

    @RequestMapping(method = RequestMethod.GET)
    public String welcomeMessage(){
        return "user";
    }
}

redirect.jsp just uses sendRedirect() method and redirects to home.jsp.

home.jsp and user.jsp just prints a simple hello message

Where I'm doing wrong?

Regards

Answer 1

Have you tried nesting the RequestMapping? Something like this...

@Controller
@RequestMapping(value = "/home")
public class HomeController {

    @RequestMapping(method = RequestMethod.GET)
    public String showHomeMessage() {
        return "home";
    }

    @RequestMapping(value = "/user", method = RequestMethod.GET)
    public String welcomeMessage(){
        return "user";
    }
}

I'm not sure if you need to put a value on showHomeMessage (i.e. value="/").

Answer 2

After looking through this little example, I think your issue is tied to the fact that you are not specifying the @ResponseBody using the @Controller annotation. Whereas, if you use the @RequestController annotation simply implying a String type would be sufficient because it combines the use of @Controller and @ResponseBody

@Controller
@RequestMapping("/home/user")
public class UserController {

    @RequestMapping(method = RequestMethod.GET)
    public @ResponseBody String welcomeMessage(){
        return "user";
    }
}

The alternative to the same block would be...

@RestController
@RequestMapping("/home/user")
public class UserController {

    @RequestMapping(method = RequestMethod.GET)
    public String welcomeMessage(){
        return "user";
    }
}

Of course this little example doesnt demonstrate MediaType and so forth, but hopefully you get the idea.