Spring MVC无法从WebApp加载静态资源


问题内容

问题 无法使Spring为静态资源添加资源处理程序。

背景信息 我有一个在独立Jetty实例中运行的Spring MVC Webapp。我的webapp结构是

webapp root/
    resources/
        css/
        images/
        js/
    WEB-INF/
        layouts/
            tiles.xml
            page.jsp
        lib/
        views/
            home/
                home.jsp
                tiles.xml
        web.xml

我扩展了,WebMvcConfigurerAdaptor以添加资源映射,以便company.com/myservlet/resources/css/main.css将类似url的地址解析到该webapp root/resources/css文件夹。

@Configuration
@EnableWebMvc
public class WebMvcConfig extends WebMvcConfigurerAdapter {

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
    }
}

我的小控制器是这样的:

@Controller
public class SpringAppController {

    public SpringAppController() {
    }

    @RequestMapping(value = "/home", method = RequestMethod.GET)
    public ModelAndView handleRequestHome(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

        return new ModelAndView("home");
    }
}

我的web.xml就是这样:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 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_2_5.xsd">

    <!-- Java-based Spring container definition -->
    <context-param>
        <param-name>contextClass</param-name>
        <param-value>org.springframework.web.context.support.AnnotationConfigWebApplicationContext</param-value>
    </context-param>

    <!-- Location of Java @Configuration classes that configure the components that makeup this application -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>com.company</param-value>
    </context-param>

    <!-- Creates the Spring Container shared by all Servlets and Filters -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!-- Processes application requests -->
    <servlet>
        <servlet-name>admin</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value></param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>admin</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!-- Ensure UTF-8 encoded pages so that certain characters are displayed and submitted correctly -->
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!-- Enables support for DELETE and PUT request methods with web browser clients -->
    <filter>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    </filter>

    <filter-mapping>
        <filter-name>hiddenHttpMethodFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

用于Web应用程序实例化某些MVC解析器的JavaConfig是这样的:

@Configuration
public class MainConfig {

    @Bean
    public ViewResolver viewResolver() {
        UrlBasedViewResolver viewResolver = new UrlBasedViewResolver();
        viewResolver.setViewClass(TilesView.class);
        return viewResolver;
    }

    @Bean
    public TilesConfigurer tilesConfigurer() {
        TilesConfigurer configurer = new TilesConfigurer();
        configurer.setDefinitions(new String[] {
            "/WEB-INF/layouts/tiles.xml",
            "/WEB-INF/views/**/tiles.xml"
        });
        configurer.setCheckRefresh(true);
        return configurer;
    }

    @Bean
    public org.springframework.context.MessageSource messageSource() {
        ReloadableResourceBundleMessageSource messageSource = new ReloadableResourceBundleMessageSource();
        messageSource.setBasename("/WEB-INF/messages/messages");
        return messageSource;
    }

}

当我访问url
company.com/myservlet/home时,磁贴内容正常运行,并且显示了home.jsp页面,但未加载CSS和图像。servlet记录以下警告:

[DEBUG] [DispatcherServlet] [DispatcherServlet with name 'admin' processing GET request for [/api/v1/tlb/resources/page.css]] 
[DEBUG] [RequestMappingHandlerMapping] [Looking up handler method for path /resources/form.css] 
[DEBUG] [RequestMappingHandlerMapping] [Did not find handler method for [/resources/form.css]]
[WARN ] [PageNotFound] [No mapping found for HTTP request with URI [/api/v1/tlb/resources/form.css] in DispatcherServlet with name 'admin']

我已经尝试调试servlet,并且WebMvcConfig.addResourceHandlers()从未调用该方法,因此为什么找不到静态资源。我缺少什么才能使它正常工作?

请注意,如果将以下内容添加到web.xml中,将加载CSS资源,但是我想知道为什么WebMvcConfig.addResourceHandlers()未调用该方法,因此不需要此servlet映射。

<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>/resources/*</url-pattern>
</servlet-mapping>

问题答案:

好吧,我已经解决了这个问题,但还不确定为什么/如何做。该项目导入了一个jar,其中包含一个扩展WebMvcConfigurationSupport如下的类:

@Configuration
public class EnableUriMatrixVariableSupport extends WebMvcConfigurationSupport {

    @Override
    @Bean
    public RequestMappingHandlerMapping requestMappingHandlerMapping() {
        RequestMappingHandlerMapping hm = super.requestMappingHandlerMapping();
        hm.setRemoveSemicolonContent(false);
        return hm;
    }
}

另外,我还具有@EnableMvc导入DelegatingWebMvcConfiguration的注释。我认为这最终会创建两个WebMvcConfigurationSupport实例,这会在spring容器中造成严重破坏。不幸的是,在解决此问题的过程中,我升级到了Spring
4.x,因此我不确定这是否有所帮助。