JAVA取得WEBROOT物理路径

引用：http://theron19.iteye.com/blog/678000

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 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">
  <context-param>
        <param-name>webAppRootKey</param-name>
        <param-value>webapp.root</param-value>
  </context-param>
  <listener>
        <listener-class>com.joshua.ApplicationListener</listener-class>
 </listener>

</web-app>

ApplicationListener.java

package com.joshua;

import javax.servlet.ServletContextEvent;

import org.springframework.web.context.ContextLoaderListener;

public class ApplicationListener extends ContextLoaderListener {

    public void contextDestroyed(ServletContextEvent sce) {
        // TODO Auto-generated method stub

    }

    public void contextInitialized(ServletContextEvent sce) {
        // TODO Auto-generated method stub
        String webAppRootKey = sce.getServletContext().getRealPath("/");
        System.setProperty("webapp.root" , webAppRootKey);
        String path =System.getProperty("webapp.root");
        System.out.println("path="+path);
    }

}