JSP中request对象URL方法对照

以 Tomcat 服务器“http://localhost:8080/vote/test.jsp”为例说明：

request.getScheme() —— http
request.getServerName() —— localhost
request.getServerPort() —— 8080
request.getContextPath() —— /vote
request.getProtocol() —— HTTP/1.1
request.getRemoteAddr() —— 127.0.0.1
request.getRemoteHost() —— 127.0.0.1
request.getRemotePort() —— 1316
request.getRequestURI() —— /vote/test.jsp
request.getRequestURL() —— http://localhost:8080/vote/test.jsp
request.getServletPath() —— /test.jsp

JSP页面中取得项目所在磁盘绝对路径：
<% pageContext.getServletContext().getRealPath("/"); %>