使用 Spring MVC 未发现映射错误

Question

合：

我希望你能帮助我。当涉及到在已经配置和设置的应用程序中工作时，我非常擅长，但另一方面，我显然不太擅长设置新应用程序 - 特别是当涉及到 Spring MVC 时。我正在尝试设置一个非常简单的应用程序，以便稍后可以在它的基础上进行构建。但当我运行它时，我收到 404 错误。一切都部署正常并编译正常，但日志显示错误：警告：在名称为“dispatcher”的 DispatcherServlet 中找不到带有 URI [/SpringTemplate/hello.htm] 的 HTTP 请求的映射。有人可以向我解释一下我做错了什么吗？我已经插入了文件 web.xml、dispatcher-servlet.xml、一些记录的条目和我的 HelloController.java 类。

web.xmldispatcher

<?xml version="1.0" encoding="UTF-8"?>
    <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" 
                           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"      xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.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>*.htm</url-pattern>
</servlet-mapping>
<session-config>
    <session-timeout>
        30
    </session-timeout>
</session-config>
<welcome-file-list>
    <welcome-file>redirect.jsp</welcome-file>
</welcome-file-list>
</web-app>

-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<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:aop="http://www.springframework.org/schema/aop"
   xmlns:tx="http://www.springframework.org/schema/tx"
   xmlns:ctx="http://www.springframework.org/schema/context"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
                       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
                       http://www.springframework.org/schema/aop
                       http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
                       http://www.springframework.org/schema/tx
                       http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
                       http://www.springframework.org/schema/context
                       http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<ctx:annotation-config />
<ctx:component-scan base-package="greenthorn.com" />

<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping"/>
<bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
    <property name="mappings">
        <props>
            <prop key="index.htm">indexController</prop>
        </props>
    </property>
</bean>

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

<!--
The index controller.
-->
<bean name="indexController"
      class="org.springframework.web.servlet.mvc.ParameterizableViewController"
      p:viewName="index" />

</beans>

成功部署后记录条目

INFO: FrameworkServlet 'dispatcher': initialization started
INFO: Refreshing WebApplicationContext for namespace 'dispatcher-servlet': startup date [Wed Nov 10 20:51:43 EST 2010]; parent: Root WebApplicationContext
INFO: Loading XML bean definitions from ServletContext resource [/WEB-INF/dispatcher-servlet.xml]
INFO: JSR-250 'javax.annotation.ManagedBean' found and supported for component scanning
INFO: JSR-330 'javax.inject.Named' annotation found and supported for component scanning
INFO: JSR-330 'javax.inject.Inject' annotation found and supported for autowiring
INFO: Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@17dca7b8: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalCommonAnnotationProcessor,org.springframework.context.annotation.internalPersistenceAnnotationProcessor,helloController,org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping#0,urlMapping,viewResolver,indexController]; parent: org.springframework.beans.factory.support.DefaultListableBeanFactory@2674b0ba
INFO: Mapped URL path [/hello] onto handler [greenthorn.com.controller.HelloController@3bbd0836]
INFO: Mapped URL path [/hello/*] onto handler [greenthorn.com.controller.HelloController@3bbd0836]
INFO: Mapped URL path [/index.htm] onto handler [org.springframework.web.servlet.mvc.ParameterizableViewController@64cbad03]
INFO: FrameworkServlet 'dispatcher': initialization completed in 454 ms
INFO: Loading application SpringTemplate at /SpringTemplate
INFO: SpringTemplate was successfully deployed in 4,749 milliseconds.

HelloController.java

package greenthorn.com.controller;

import login.Passwordproperties;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import greenthorn.com.service.HelloService;
import greenthorn.com.service.PasswordService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
public class HelloController {
    private HelloService helloService;

    public HelloController() {}

    /**
     * @param helloService the helloService to set
     */
    @Autowired
    public void setHelloService(HelloService helloService) {
        this.helloService = helloService;
    }

    @RequestMapping("/hello.htm")
    public ModelAndView onSubmit(@ModelAttribute("command") Name command) throws Exception {
        ModelAndView mv = new ModelAndView("helloView");
        mv.addObject("helloMessage", helloService.sayHello(command.getValue()));
        mv.addObject("greeting", "Thanks for dropping by...");
        return mv;
    }
}

Answer 1

在当前配置中，由于 ControllerClassNameHandlerMapping，HelloController.onSubmit() 映射到 /hello/hello.htm。

如果想映射到/hello.htm，需要将ControllerClassNameHandlerMapping替换为DefaultAnnotationHandlerMapping（通常默认使用这个映射，但是在您的情况下，不应用默认值，因为您手动声明处理程序映射）。

Answer 2

失败的原因可能是参数“@ModelAttribute(“command”) Name command”。
这种类型的参数通常用于post方法。