spring框架的思路, 在WEB-INF/web.xml中 ， 创建一个webAppRootKey的param, 指定一个值（默认为webapp.root）作为键值， 然后通过Listener , 或者Filter , 或者Servlet 执行String webAppRootKey = getServletContext().getRealPath("/"); 并将webAppRootKey对应的webapp.root 分别作为Key , Value写到System Properties系统属性中。之后在程序中通过System.getProperty("webapp.root")来获得WebRoot的物理路径.

web.xml

<?xml version="1.0" encoding="UTF-8"?> <web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <display-name>SpringFlex</display-name> <context-param> <param-name>webAppRootKey</param-name> <param-value>webapp.root</param-value> </context-param> <servlet> <servlet-name>Spring MVC Servlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext*.xml</param-value> </init-param> </servlet> <servlet> <servlet-name>SetWebRootKeyServlet</servlet-name> <servlet-class>com.sf.system.SetWebRootKeyServlet</servlet-class> <load-on-startup>2</load-on-startup> </servlet> <servlet-mapping> <servlet-name>Spring MVC Servlet</servlet-name> <url-pattern>/messagebroker/*</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.htm</welcome-file> <welcome-file>index.jsp</welcome-file> <welcome-file>default.html</welcome-file> <welcome-file>default.htm</welcome-file> <welcome-file>default.jsp</welcome-file> </welcome-file-list> <login-config> <auth-method>BASIC</auth-method> </login-config> <!-- for WebSphere deployment, please uncomment <resource-ref> <description>Flex Messaging WorkManager</description> <res-ref-name>wm/MessagingWorkManager</res-ref-name> <res-type>com.ibm.websphere.asynchbeans.WorkManager</res-type> <res-auth>Container</res-auth> <res-sharing-scope>Shareable</res-sharing-scope> </resource-ref --> </web-app>

相应servlet

/** * */ package com.sf.system; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; /** * @author Administrator * */ public class SetWebRootKeyServlet extends HttpServlet { @Override public void init() throws ServletException { // TODO Auto-generated method stub super.init(); String webAppRootKey = getServletContext().getRealPath("/"); System.setProperty("webapp.root", webAppRootKey); } }

使用的代码：System.out.println(System.getProperty("webapp.root"));