Spring 3 RequestMapping：获取路径值

Question

requestMapping@PathVariable的值被解析后有没有办法得到完整的路径值？

即： /{id}/{restOfTheUrl} 应该能够将/1/dir1/dir2/file.html 解析为id=1 和restOfTheUrl=/dir1/dir2/file.html

任何想法都将不胜感激。

Answer 1

URL 的不匹配部分被暴露为名为@9​​87654321@ 的请求属性：

@RequestMapping("/{id}/**")
public void foo(@PathVariable("id") int id, HttpServletRequest request) {
    String restOfTheUrl = (String) request.getAttribute(
        HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
    ...
}

Answer 2

我使用 Tuckey URLRewriteFilter 来处理包含“/”字符的路径元素，因为我认为 Spring 3 MVC 还不支持它们。

http://www.tuckey.org/

您将此过滤器放入您的应用程序中，并提供一个 XML 配置文件。在该文件中，您提供了重写规则，您可以使用这些规则将包含“/”字符的路径元素转换为 Spring MVC 可以使用 @RequestParam 正确处理的请求参数。

WEB-INF/web.xml：

<filter>
  <filter-name>UrlRewriteFilter</filter-name>
  <filter-class>org.tuckey.web.filters.urlrewrite.UrlRewriteFilter</filter-class>
</filter>
<!-- map to /* -->

WEB-INF/urlrewrite.xml：

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE urlrewrite
    PUBLIC "-//tuckey.org//DTD UrlRewrite 3.0//EN"
    "http://tuckey.org/res/dtds/urlrewrite3.0.dtd">
<urlrewrite>
  <rule>
    <from>^/(.*)/(.*)$</from>
    <to last="true">/$1?restOfTheUrl=$2</to>
</urlrewrite>

控制器方法：

@RequestMapping("/{id}")
public void handler(@PathVariable("id") int id, @RequestParam("restOfTheUrl") String pathToFile) {
  ...
}

Answer 3

刚刚发现与我的问题相对应的问题。使用 HandlerMapping 常量，我可以为此目的编写一个小实用程序：

/**
 * Extract path from a controller mapping. /controllerUrl/** => return matched **
 * @param request incoming request.
 * @return extracted path
 */
public static String extractPathFromPattern(final HttpServletRequest request){


    String path = (String) request.getAttribute(
            HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
    String bestMatchPattern = (String ) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);

    AntPathMatcher apm = new AntPathMatcher();
    String finalPath = apm.extractPathWithinPattern(bestMatchPattern, path);

    return finalPath;

}

Answer 4

我有类似的问题，我是这样解决的：

@RequestMapping(value = "{siteCode}/**/{fileName}.{fileExtension}")
public HttpEntity<byte[]> getResource(@PathVariable String siteCode,
        @PathVariable String fileName, @PathVariable String fileExtension,
        HttpServletRequest req, HttpServletResponse response ) throws IOException {
    String fullPath = req.getPathInfo();
    // Calling http://localhost:8080/SiteXX/images/argentine/flag.jpg
    // fullPath conentent: /SiteXX/images/argentine/flag.jpg
}

请注意，req.getPathInfo() 将返回完整路径（带有{siteCode} 和{fileName}.{fileExtension}），因此您必须方便地处理。

Answer 5

private final static String MAPPING = "/foo/*";

@RequestMapping(value = MAPPING, method = RequestMethod.GET)
public @ResponseBody void foo(HttpServletRequest request, HttpServletResponse response) {
    final String mapping = getMapping("foo").replace("*", ""); 
    final String path = (String) request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
    final String restOfPath = url.replace(mapping, "");
    System.out.println(restOfPath);
}

private String getMapping(String methodName) {
    Method methods[] = this.getClass().getMethods();
    for (int i = 0; i < methods.length; i++) {
        if (methods[i].getName() == methodName) {
            String mapping[] = methods[i].getAnnotation(RequestMapping.class).value();
            if (mapping.length > 0) {
                return mapping[mapping.length - 1];
            }
        }
    }
    return null;
}

Answer 6

是的，restOfTheUrl 不仅返回所需的值，但我们可以通过使用 UriTemplate 匹配来获取该值。

我已经解决了这个问题，所以这里是该问题的有效解决方案：

@RequestMapping("/{id}/**")
public void foo(@PathVariable("id") int id, HttpServletRequest request) {
String restOfTheUrl = (String) request.getAttribute(
    HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
    /*We can use UriTemplate to map the restOfTheUrl*/
    UriTemplate template = new UriTemplate("/{id}/{value}");        
    boolean isTemplateMatched = template.matches(restOfTheUrl);
    if(isTemplateMatched) {
        Map<String, String> matchTemplate = new HashMap<String, String>();
        matchTemplate = template.match(restOfTheUrl);
        String value = matchTemplate.get("value");
       /*variable `value` will contain the required detail.*/
    }
}

Answer 7

这就是我的做法。您可以看到我如何将请求的URI 转换为文件系统路径（这个 SO 问题是关于什么的）。奖励：以及如何响应文件。

@RequestMapping(value = "/file/{userId}/**", method = RequestMethod.GET)
public void serveFile(@PathVariable("userId") long userId, HttpServletRequest request, HttpServletResponse response) {
    assert request != null;
    assert response != null;

    // requestURL:  http://192.168.1.3:8080/file/54/documents/tutorial.pdf
    // requestURI:  /file/54/documents/tutorial.pdf
    // servletPath: /file/54/documents/tutorial.pdf
    // logger.debug("requestURL: " + request.getRequestURL());
    // logger.debug("requestURI: " + request.getRequestURI());
    // logger.debug("servletPath: " + request.getServletPath());

    String requestURI = request.getRequestURI();
    String relativePath = requestURI.replaceFirst("^/file/", "");

    Path path = Paths.get("/user_files").resolve(relativePath);
    try {
        InputStream is = new FileInputStream(path.toFile());  
        org.apache.commons.io.IOUtils.copy(is, response.getOutputStream());
        response.flushBuffer();
    } catch (IOException ex) {
        logger.error("Error writing file to output stream. Path: '" + path + "', requestURI: '" + requestURI + "'");
        throw new RuntimeException("IOError writing file to output stream");
    }
}

Answer 8

这已经在这里很长一段时间了，但发布了这个。可能对某人有用。

@RequestMapping( "/{id}/**" )
public void foo( @PathVariable String id, HttpServletRequest request ) {
    String urlTail = new AntPathMatcher()
            .extractPathWithinPattern( "/{id}/**", request.getRequestURI() );
}

Answer 9

你需要使用内置的pathMatcher:

@RequestMapping("/{id}/**")
public void test(HttpServletRequest request, @PathVariable long id) throws Exception {
    ResourceUrlProvider urlProvider = (ResourceUrlProvider) request
            .getAttribute(ResourceUrlProvider.class.getCanonicalName());
    String restOfUrl = urlProvider.getPathMatcher().extractPathWithinPattern(
            String.valueOf(request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE)),
            String.valueOf(request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE)));

Answer 10

在Fabien Kruba's already excellent answer 的基础上，我认为如果URL 的** 部分可以通过注释作为参数提供给控制器方法会很好，其方式类似于@RequestParam 和@ 987654324@，而不是总是使用明确需要HttpServletRequest 的实用程序方法。所以这里有一个如何实现的例子。希望有人觉得它有用。

创建注释以及参数解析器：

@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface WildcardParam {

    class Resolver implements HandlerMethodArgumentResolver {

        @Override
        public boolean supportsParameter(MethodParameter methodParameter) {
            return methodParameter.getParameterAnnotation(WildcardParam.class) != null;
        }

        @Override
        public Object resolveArgument(MethodParameter methodParameter, ModelAndViewContainer modelAndViewContainer, NativeWebRequest nativeWebRequest, WebDataBinderFactory webDataBinderFactory) throws Exception {
            HttpServletRequest request = nativeWebRequest.getNativeRequest(HttpServletRequest.class);
            return request == null ? null : new AntPathMatcher().extractPathWithinPattern(
                    (String) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE),
                    (String) request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE));
        }

    }

}

注册方法参数解析器：

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Override
    public void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {
        resolvers.add(new WildcardParam.Resolver());
    }

}

在控制器处理程序方法中使用注释可以轻松访问 URL 的 ** 部分：

@RestController
public class SomeController {

    @GetMapping("/**")
    public void someHandlerMethod(@WildcardParam String wildcardParam) {
        // use wildcardParam here...
    }

}

Answer 11

改进@Daniel Jay Marcaida 的回答

@RequestMapping( "/{id}/**" )
public void foo( @PathVariable String id, HttpServletRequest request ) {
    String restOfUrl = new AntPathMatcher()
           .extractPathWithinPattern(
            request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE).toString(),
            request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE).toString());
}

或

@RequestMapping( "/{id}/**" )
public void foo( @PathVariable String id, HttpServletRequest request ) {
    String restOfUrl = new AntPathMatcher()
    .extractPathWithinPattern(
            request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE).toString(),
            request.getServletPath());
}