http://www.jb51.net/article/71693.htm
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本文介绍了Java获取此次请求URL以及获取服务器根路径的方法，并且进行举例说明，感兴趣的朋友可以学习借鉴下文的内容。
一、 获取此次请求的URL
String requestUrl = request.getScheme() //当前链接使用的协议 +"://" + request.getServerName()//服务器地址 + ":" + request.getServerPort() //端口号 + request.getContextPath() //应用名称，如果应用名称为 + request.getServletPath() //请求的相对url + "?" + request.getQueryString(); //请求参数
举例：
http://127.0.0.1:8080/world/index.jsp?name=lilei&sex=1 <Context path="world" docBase="/home/webapps" debug="0" reloadable="true"/> request.getScheme() = "http"; request.getServerName() = "127.0.0.1"; request.getServerPort() = "8080"; request.getContextPath() = "world"; request.getServletPath() = "index.jsp"; request.getQueryString() = "name=lilei&sex=1"; http://127.0.0.1:8080/world/index.jsp?name=lilei&sex=1 <Context path="" docBase="/home/webapps" debug="0" reloadable="true"/> request.getScheme() = "http"; request.getServerName() = "127.0.0.1"; request.getServerPort() = "8080"; request.getContextPath() = ""; request.getServletPath() = "world/index.jsp"; request.getQueryString() = "name=lilei&sex=1";
二、获取服务器根路径
<% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %>
使用如下：
<head> <link rel="stylesheet" type="text/css" href="<%=basePath%>static/css/framework/themes/default/easyui.css"> <link rel="stylesheet" type="text/css" href="<%=basePath%>static/css/framework/themes/icon.css"> <link rel="stylesheet" type="text/css" href="<%=basePath%>static/css/base.css"> <script src="<%=basePath%>static/javascript/framework/jquery.min.js"></script> <script src="<%=basePath%>static/javascript/framework/jquery.easyui.min.js"></script> <script src="<%=basePath%>static/javascript/framework/easyui-lang-zh_CN.js"></script> <script src="<%=basePath%>static/javascript/framework/easyui-util.js"></script> </head>
原文：http://www.cnblogs.com/zhao1949/p/7635301.html