Spring MVC 不从 webapp 加载静态资源

Question

问题 无法让 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

我已扩展 WebMvcConfigurerAdaptor 以添加资源映射，以便 company.com/myservlet/resources/css/main.css 之类的 URL 将解析到 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 就是这样的：

<?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>

我的 webapp 用于实例化一些 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;
    }

}

当我点击 url company.com/myservlet/home 时，瓷砖的东西可以工作，并且会显示 home.jsp 页面，但没有加载 css 和图像。 servlet 记录此警告：

[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']

我尝试过调试 servlet，但从未调用过 WebMvcConfig.addResourceHandlers() 方法，因此无法找到静态资源。让这个工作我缺少什么？

作为一个注释，如果我将以下内容添加到我的 web.xml 中，css 资源将被加载，但我想知道为什么不调用 WebMvcConfig.addResourceHandlers() 方法，所以我不需要这个 servlet 映射。

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

Answer 1

嗯，我已经解决了这个问题，但还不确定为什么/如何。该项目已导入一个 jar，其中包含一个扩展 WebMvcConfigurationSupport 的类，如下所示：

@Configuration
public class EnableUriMatrixVariableSupport extends WebMvcConfigurationSupport {

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

此外，我还有 @EnableMvc 注释，它可以导入 DelegatingWebMvcConfiguration。我认为这最终会创建 WebMvcConfigurationSupport 的两个实例，这会在 spring 容器中造成严重破坏。不幸的是，我在修复这个问题的过程中升级到了 spring 4.x，所以我不确定这是否在某种程度上有所帮助。