Spring Web的UrlPathHelper的主要方法

基于Spring Web开发的应用，下面这几个方法比较经常使用，标记一下

/**
 * Return the mapping lookup path for the given request, within the current
 * servlet mapping if applicable, else within the web application.
 * <p>Detects include request URL if called within a RequestDispatcher include.
 * @param request current HTTP request
 * @return the lookup path
 * @see #getPathWithinApplication
 * @see #getPathWithinServletMapping
 */
public String getLookupPathForRequest(HttpServletRequest request)

/**
 * Return the path within the servlet mapping for the given request,
 * i.e. the part of the request's URL beyond the part that called the servlet,
 * or "" if the whole URL has been used to identify the servlet.
 * <p>Detects include request URL if called within a RequestDispatcher include.
 * <p>E.g.: servlet mapping = "/*"; request URI = "/test/a" -> "/test/a".
 * <p>E.g.: servlet mapping = "/"; request URI = "/test/a" -> "/test/a".
 * <p>E.g.: servlet mapping = "/test/*"; request URI = "/test/a" -> "/a".
 * <p>E.g.: servlet mapping = "/test"; request URI = "/test" -> "".
 * <p>E.g.: servlet mapping = "/*.test"; request URI = "/a.test" -> "".
 * @param request current HTTP request
 * @return the path within the servlet mapping, or ""
 */
public String getPathWithinServletMapping(HttpServletRequest request)

/**
 * Return the path within the web application for the given request.
 * <p>Detects include request URL if called within a RequestDispatcher include.
 * @param request current HTTP request
 * @return the path within the web application
 */
public String getPathWithinApplication(HttpServletRequest request)

使用spring boot+Freemarker，模版名称后缀是.html，请求的路径中.html，可能包括静态资源和模版资源，spring boot会优先检查静态资源是否存在，若是存在，就不会再查询模版资源了，但spring boot中缺省的静态资源检查路径有5个，检查太多了，而且，因为静态资源缺省定在main/resources下，这里的资源必须通过编译发布部署，开发阶段，静态资源改了，刷新比较麻烦，此处直接更改静态资源到绝对路径：file:///media/dd，此种方式有两种：

第一种：

application.yml中

spring

  resources

    static-locations:

      - file:///

这种方式，是很是简单的，也比较高效，但若是访问的资源来自模版，则还要检查4次

第二种：

自定义一个环境配置,spring.static.location=${project.root}/xxx

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/**")
            .addResourceLocations(staticLocation)
            .setCachePeriod(0);
}

这种方式，只检查一个location,感到要省时一些，但多了一个自定义配置，而且解决了刷新问题，这个是关键